803Deep Foundations

803.01 General.

803.01.1 Description. This work consists of furnishing and installing deep foundations

in accordance with these specifications and in reasonable conformance with the lines, elevations, and spacings shown on the plans. It shall also consist of furnishing all required labor, tools, and equipment to determine the bearing value of the deep foundation by static load testing, by dynamic load testing, and/or by driving of the specified test piles.

803.01.2 Order Lists for Deep Foundations. Lengths found in the plans are estimated

lengths for bid purposes. Unless otherwise specified or authorized in writing by the Bridge Engineer, all permanent deep foundations shall be installed within the prescribed tolerances specified herein and to the depths and/or lengths indicated on the itemized Order List furnished by the Engineer. The Order List shall be furnished after bearing has been verified either through static load testing, dynamic load testing, and/or driving of the specified test piles. The Contractor shall furnish or install driven piles and/or drilled shafts in accordance with an itemized list furnished by the Engineer. The Order List will show the required length of the piles or drilled shafts fo r each bridge bent or footing.

803.02 Materials. All materials shall conform to the a pplicable requirements set forth in

Sections 710, 711, 719, 804, and 814. Driven piles shall conform to all applicable requirements set forth in Section 719 and the plans. Paint for steel piles or steel shells shall conform to the applicable requirements of Sections 710 and 814. Drilled shaft concrete shall conform to the re quirements of Section 804 for Class “DS” concrete. All reinforcing steel shall conform to the requirements of Section 711 of the Specifications.

803.03 Construction Requirement . This work shall consist of furnishing all labor,

materials, equipment and services necessary to install driven piles of the prescribed type in accordance with these specifications and in co nformance with the lin es, elevations, and spacings shown on the plans. This work shall also consist of furnishing all labor, materials, equipment and services necessary to perform all operations to complete the drilled shaft insta llations in accordance with these specifications and with the details and dimensions shown on the plans. Drilled shafts shall consist of reinforced or non-reinforced concrete with or without concrete bell footings.

803.03.1 Driven Piles.

803.03.1 1--General. Unless otherwise specified or author ized by the Bridge Engineer, all

permanent production piles shall be driven in a continuous operation, to the full lengths indicated on the itemized order list furnished by the Bridge Engineer.

803.03.1 2--Accuracy of Installation. Driven piles in trestle bents shall be driven to

within a tolerance of 1/4 inch per foot from the vertical or from the batter shown on the plans. Piles to be incorporated into a cap or footing shall not be out of the position shown on the plans by more than six inches. In all ca ses, piles shall be driven so that they will not be excessively stressed to place them in the prope r location in the cap or footing. Excessive manipulation of the piles will not be permitted, and the Contractor shall re-drive or use other satisfactory methods to avoid such manipulations. No shimming on tops of piles will be permitted.

803.03.1 3--Extensions, Build-ups and Splices. If determined by the Engineer to be

necessary, production piles that are extended below cut-off shall be extended, built-up, or spliced in accordance with the plans to the extent established by the Bridge Engineer. Extensions or build-ups will not be measured for payment as such, but will be included in the total length of piling in the finished structure.

803.03.1 4--Cut-Offs. If it is determined by the Engineer that the pile has reached practical

refusal above pile cut-off elevation but below the prescribed minimum tip elevation shown in the plans then the Contractor will be allowed to cut off the pile at the cut-off elevation.

803.03.1 5--Driven Pile Types. Driven piles shall be of the type listed below unless

otherwise specified in the plans.

803.03.1 5.1--Con crete Piles. Concrete piles shall be the size and shape specified.

Reinforcement, unless otherwise designated, sh all have a clear distance of at least two inches from the face of the pile. When the piles are for use in salt water or alkali soils this clear distance shall be at least three inches.

803.03.1 5.2--Steel Piles. Full-length steel piles shall be used unless splicing is approved

in writing by the Bridge Engineer. When pe rmitted, splicing shall be in accordance with the notes and details shown on the plans.

803.03.1 5.3--Timber Piles. Specified timber piles or timb er piles used for temporary

construction shall meet the requirements set forth in Section 820.

803.03.1 5.4--Special Piles. Piles not of the type specified above, but called for in the

plans or additional specifications shall meet the general requirements contained therein.

803.03.1 5.5--Steel Pipe Piling . When permitted, steel pipe pile splices shall be made by

a certified welder in accordance with AWS D1.1 or as approved by the Engineer. Either shielded arc or submerged arc welding should be used when splicing steel pipe piles. Any damaged portion of the pile top shall be cut off before splicing. Unless otherwise indicated by the plans, the pipe pile ends may be flame cut. The Contractor shall take care to align the sections prior to splicing so that the axis of the pile is straight. Splices of steel pipe piles shall form a watertight joint and shall not extend beyond the pipe pile OD. Pipe pile splices within the epoxy coated se ction require removal and re-application of the specified epoxy coating at the weld location.

803.03.1 6--Preparation for Driving.

803.03.1 6.1--Excavation. When a pile cap is located below the ground line, piles shall

not be driven until the required excavation is completed. All material forced up between the piles shall be removed to the correct el evation at the Contractor’s expense before concrete for the foundation is placed. 803.03.1.6.2--Pile Cushions. Suitable cushioning material shall be used between the driving helmet and the top of the pile. This is especially critical for concrete piles. The Contractor should submit the type material, cross-sectional area, and total thickness of the pile cushion to the Engineer for approval on the completed Pile Driving Equipment Data Form. The pile cushion shall be approved with the pile driving system and is subject to satisfactory field performance.

803.03.1 7--Method of Installation and Driving System.

803.03.1 7.1--General. The pile driving system is defined as all equipment necessary to

install the specified piles to the required minimum tip elevations specified in the plans. The pile driving system shall include the pile hammer, hammer leads, followers, water jets, drilling equipment for pre-formed pile holes, and templates, if necessary.

803.03.1 7.2--Submittal of Pile Driving System Data. The Contractor shall submit to the

Engineer all technical specifications and operating instructions relating to the pile driving system that is to be used to drive the piling. The Contractor shall also submit a completed Pile and Driving Equipment Data Form to the Engineer at the pre-construction conference or no later than 14 days prior to the anticipated driving date. The Contractor will not be allowed to install any piling until the driving system has been approved in writing by the Engineer. The Department will use the submitted information to perform wave equation analysis and prepare a summary report of the wave equation results. The wave equation analysis and other data shall be used to assess the ability of the proposed systems to install the piles to the desired penetration depth within the AASHTO standards for driving stresses. The Engineer will notify the Contractor of any additional information required and/or changes that may be necessary to meet the pr oject requirements. Any parts of the driving system that are unacceptable will be rejected and the Contractor will submit changes. Review of these changes will be completed within seven (7) days and the Contractor notified of their acceptance or re jection. Approval of the pr oposed driving system by the Engineer for driving of test piles shall be based upon the wave equation analysis indicating that the proposed driving system is acceptable. All production piles shall be driven with the hammer bear ing the same Serial Number submitted on the Pile and Driving Equipment Data Form and used to drive the test piles. In the event multiple hammers of differing type are used on the same bridge, the Contractor shall submit to the Engineer for approval a completed Pile and Driving Equipment Data Form for each hammer and specify the bridge bents in which each hammer will be used. This will allow the Department the opportunity to develop appropriate driving and acceptance criteria specific to each hammer. A different pile driving system, modifications to the existing system, or different pile installation procedures shall be proposed by th e Contractor if the pile installation stresses predicted by the wave equation analysis or calculated by the Pile Driving Analyzer (PDA) are not within the AASH TO values. All approvals are c onditional and subject to trial and satisfactory performance in the field. Unless otherwise permitted by the Bridge Engineer in writing, test piles and permanent piles shall be driven with the approved driving system.

803.03.1 7.3--Pile Hammers. Piles may be driven with an approved single-acting or

double-acting pile hammer in combination with water jets or pre-formed pile holes. The pile driving system shall be constructed so as to afford freedom of movement of the pile hammer and to drive the piles to the required depth within the tolerances specified without undue injury to the piles. The pile hammer shall be in good working condition and produce the energy required to install piles to the depth or penetration required in the plans. Single or double-acting Steam/Air, Diesel/Internal Combustion, or Hydraulic hammers may be submitted for review and approval. In no case shall a gravity or drop hammer be used to drive concrete or steel piles supporting the permanent bridge structure. A drop hammer may be used to install timber or steel piles for temporary construction, but in no case sha ll a gravity or drop hammer be used to drive concrete piles.

803.03.1 7.3 .1--Pipe Pile Hammers.

803.03.1 7.3 .1.1--Impact Hammers. Piles may be driven with an approved single-acting

or double-acting pile hammer, as recommended on the plans, in combination with water jets or pre-formed pile holes. The pile drivi ng system shall be constructed so as to afford freedom of movement of the pile hammer and to drive the piles to the required depth within the tolerances specified without undue injury to the piles. The pile hammer shall be in good working condition and produce the energy required to install piles to the depth or penetration required in the plans. Single or double-acting Steam/Air, Diesel/Internal Combustion, or Hydraulic hammers may be submitted for review and approval. In no case shall a gravity or drop hammer be used to drive concrete or steel piles supporting the permanent bridge structure. A drop hammer may be used to install timber or steel piles for temporary construction, but in no case sha ll a gravity or drop hammer be used to drive concrete piles.

803.03.1 7.3.1 .2--Vibratory Hammers. Vibratory hammers in good working condition

may be used to advance steel pipe piles to with in twenty feet (20’) of minimum tip elevation of production pile for PDA Test Piles and five feet (5’) of minimum pile tip elevation for permanent piles. Vibratory ha mmers shall be attached centra lly to the pile head. Under no circumstances can vibratory hammers be used to advance steel pipe piles for the last five feet (5’) of pile length. The Contractor may have the option to use a vibratory hammer to drive the steel pipe pile within five feet (5’) of minimum pile tip elevation for permanent piles.

803.03.1 7.4--Driving Appurtenances.

803.03.1 7.4.1 --Pile Hammer Leads. Either fixed leads or swinging leads may be used.

Swinging leads shall be used in combination with rigid templates approved by the Engineer. Battered piles shall be driven in inclined leads or multiple rigid templates capable of holding the pile in the proper position during driving.

803.03.1 7.4.2--Pile Cushions. Suitable cushioning material shall be used between the

driving cap and the top of the pile. The cushion material shall protect the pile top during driving and shall be constructed such that the hammer energy is uniformly distributed to the pile top. The pile cushion shall be changed prior to driving each pile. In addition, if the cushion material becomes highly compressed, or chars or burns during the driving operations or damage occurs at the pile top, it shall be replaced. The type of material and dimensions of the pile cushion shall be included in the appropriate place on the Pile and Driving Equipment Data Form.

803.03.1 7.4.3--Water Jets. Water jets may be used in conjunction with the pile hammer

to install piles to the required depth or penetration called for in the plans. The use of water jets, where the stability of embankments or ot her improvements would be endangered, will not be permitted. When water jets are used, the number of jets and the volume and pressure of water shall be sufficient to adequately facilitate driving without undue damage to the pile or the soil adjacent to or below the pile. Unless otherwise specified, water jets shall not be used within five feet of the final tip elevation of the pile. In addition, it shall be the Contractor’s responsibility to withdraw the wa ter jets sufficiently above the five foot requirement to obtain the sp ecified bearing at the requ ired cut off elevation. In the event a jetted pile fails to obtain the specified bearing at the required penetration and a determination is made by the Engineer that the Contractor has failed to properly control the jetting operation, the Contractor shoul d submit detailed corrective measures for founding the pile to the Engineer for approval. Any required corrective measures to the pile due to the Contractor’s operation shall be performed at no additional cost to the State.

803.03.1 7.4.4--Followers. Followers are considered to be part of the Driving System and

should be included for approval with the Pile and Driving Equipment Data Form. Included with the submittal should be a dimensioned sketch of the follower. Also, the type(s) of materials that the follower is made of and the weight of the follower should be included as well as cushion information.

803.03.1 7.4.5--Pre-formed Pile Holes. The Bridge Engineer will make all

determinations as to the necessity for pre-formed pile holes and the size and maximum depth of each hole required or permitted. If it is determined from the Geotechnical Investigation or from the site survey that pre- formed pile holes are necessary, a pay item and estimated quantities will be included on the plans, and the Bridge Engineer will furnis h the Contractor with an itemized list showing the location, size and bottom elevation of each hole. If the plans do not specify pre-formed pile holes and the Bridge Engineer, with the concurrence of the Construction Engineer, determines during construction that subsurface conditions are encountered that necessitate pre-formed pile holes, at certain locations, an adjustment in the contract unit price for furnishing and driving piling at these locations may be made under the provisions of Subsection 104.02. If in the judgment of the Engineer pre-formed pile holes are not required and the Contractor desires to use them, the Contractor may be permitted to do so under conditions prescribed by the Bridge Engineer and at no additional cost to the State. For pipe piling, the indicator pile and the first production steel pipe test pile shall be driven without a pre-formed hole. Based on the resu lts, the Director of Structures, State Bridge Engineer, will make all determinations as to the necessity for pre-formed holes on all subsequent steel pipe test piles and steel pipe production piles. If it is determined that preformed holes are necessary, the Director of Structures, State Bridge Engineer, will furnish the Contractor with an itemized list showing the location, size, and bottom elevation of each hole. If in the judgment of the Director of Struct ures, State Bridge Engineer, pre-formed holes for pipe piling are not required and the Contractor desires to use them, the Contractor may be permitted to do so under conditions prescribed by the Director of Structures, State Bridge Engineer, and at no additional cost to the State.

803.03.1 7.4.6--Additional Equipment. When a minimum penetration is indicated on the

plans and is not obtained by the use of an approved hammer, the Contractor shall submit to the Engineer for approval a completed Pile and Driving Equipment Data Form for a heavier hammer or resort to jetting at no additional cost to the State.

803.03.1 8--Defective Piles. Prior to driving, piles shall not be subjected to handling that

causes damage either through bending, crushing or spalling of concrete, or deformation of the steel. All piles damaged because of internal defects or by improper driving, driven out of the proper location or driven below the sp ecified elevation shall be corrected at the Contractor’s expense by one of the following methods approved by the Engineer for the pile in question:

803.03.1 9--Determination of Bearing Value of Piling.

803.03.1 9.1--General. The ability of the pile to transf er load to the ground will be

determined to the satisfaction of the Bridge Engineer. Such determination will be made by the Department’s Geotechnical Engineer and Foundation Engineer from a subsurface investigation conducted by the Department’s Geotechnical Branch of Materials Division and test piles that are driven out-of-position or driven to be incorporated in the structure as permanent piles.

803.03.1 9.2--Det ermination of Bearing Value by Pile Hammer Formulas. When load

testing, either static or dynamic, is not calle d for in the plans, the safe bearing values will be determined by the following formulas or as directed by the Engineer. Pൌ 2WH S൅0.2 for single-acting steam/air hammers and open cylinder diesel hammers Pൌ 2H(W+Ap) S+0.1 for double-acting steam hammers Where P = safe bear ing value in pounds W = weight, in pounds, of striking parts of hammer H = height of fall in feet A = area of piston in square inches p = steam/air pressure in pounds per square inch at the hammer S = the average penetration in 10 blows for gravity hammers and the last 10 to 20 blows for steam/air hammers. These formulas are applicable for the following conditions only:

803.03.1 9.3--Det ermination of Bearing Value by PDA Monitoring (Dynamic Load

Testing).

803.03.1 9.3.1--Description. This work consists of furnishing all labor, materials,

equipment and services necessary to perform all operations to complete the determination of bearing value of piling by Department for ces using a PDA and asso ciated equipment. The dynamic load testing measurements will be performed in accordance with the plans and the guidelines given herein. 803.03.1.9.3.2--Scope and Sequence of Construction. The dynamic measurements will be performed on the piles as detailed below for the purpose of obtaining ultimate pile bearing capacity, pile driving stresses, pile inte grity, and the pile driving system efficiency. Unless otherwise directed in the plans, the sequence of construction outlined below shall not be deviated from unless an alternate sequence of construction is approved in writing by the Engineer.

803.03.1 9.3.3--PDA Monitored Driv ing and/or Restrike of Piling.

803.03.1 9.3.3.1--General. When called for in the plans or the Engineer, a PDA and

instrumentation will be used to obtain dynamic measurements during pile driving and pile restrikes. The analysis of the monitoring will be the responsibility of the Department. The Contractor shall give notice to the State Geot echnical Engineer at least 14 calendar days before the scheduled date of driving piles to be monitored. The Contractor shall confirm the driving date three (3) calendar days prior to the scheduled driving date.

803.03.1 9.3.3 .2--Contractor Requirements. The Contractor shall be responsible for

furnishing the following:

803.03.1 9.3 .3.3--Driving Requirements. Piles to be used in the determination of pile

bearing by PDA monitoring shall be driven with PDA instrumentation attached to the pile and shall have a PDA monitored 1-day and 7-day restrike performed after the initial pile driving. The Engineer may modify the waiting periods that are required before the restrikes are performed. When a static load test is to be performed, the 7-day restrike should be eliminated and a PDA monitored restrike done within 24 hours of completion of the static load test. When deemed necessary by the Engineer, permanent piles may have PDA monitored restrikes performed to confirm or supplement design requirements. Restrikes shall be performed with a warm ha mmer operating at normal efficiency. A warm hammer is defined as a hammer that has applied a minimum of 20 blows to another pile or a dummy block immediately before being used in a restrike. The restrike shall consist of striking the pile for 50 blows or until the pile penetrates an additional three inches, whichever occurs first. In the event the pile movement is less than one inch after 15 blows during the restrike, the restrike may be terminated.

803.03.1 9.4--Det ermination of Bearing Value by Static Load Testing. When called for

in the plans or directed by the Engineer, static load testing will be conducted to determine the ultimate bearing capacity of piles. Depending upon the conditions encountered in the field, the Bridge Engineer may increase or decr ease the number of static load tests required.

803.03.1 9.4.1--Load Testing of P iling With Special Instrumentation.

803.03.1 9.4.1.1--General. When called for in the plans, out-of-position test piles shall be

driven with special instrumentation attached for the purpose of conducting a load test as directed by the plans. A waiting period of seven (7) calendar days shall be observed beginning after the out-of-position test pile is driven. After the waiting period, the pile shall be load tested to failure as directed by the plans. The Contractor will be responsible for furnishing all materials, equipment, labor, and incidentals necessary for conducting the load test. The Contractor shall subcontract and supply all instrumentation, conducting, and reporting of the load test to the company supplying the instrumentation, with the cost included in the contract unit price. Reaction systems and extra pile installations as required in the plans shall be absorbed in the cost for the load test on the pile.

803.03.1 9.4.1.2--Materials. When called for in the plans, instrumentation shall be

supplied to meet the requirements set forth in the plans. Instrumentation required in the plans is subject to prior approval by the State Geotechnical Engineer. Additional equipment that may be required are as follows.

803.03.1 9.4.2--Conventional Static Load Testing of Piling.

803.03.1 9.4.2.1--General. When called for in the plans or directed by the Engineer, the

pile to be load tested shall be installed as in dicated in the plans to th e specified tip elevation or as directed by the Engineer. Once the pile is in place, a static load test will be conducted to determine the ultimate bearing capacity of the pile. A waiting period of seven (7) calendar days shall be observed beginning afte r all the reaction piles have been driven but prior to static load testing.

803.03.1 9.4.2 .2--Contractor Requirements. The Contractor shall be responsible for

furnishing the following:

803.03.1 9.4.2.3--Methods and Equipment. Personnel from the Department’s

Geotechnical Branch will assist in the setup and will be responsible for the running of the test. The Department will be responsible for providing the load cell, dial gauges and associated equipment. The static load test will be performed using ASTM D 1143, quick test methods. A waiting period of seven (7) calendar days shall be observed beginning after all the reaction piles have been driven but prior to static load testing. Static Load Test Note: Drawing Not to Scale Figure 1

803.03.1 10--Pile Acceptance. The safe allowable load for each type, size, and length of

pile will be determined by the Bridge Engineer. Acceptance criteria for permanent production piles will be supplied by the Bridge Engineer with the final order list.

803.03.1 11--Test Piles. When required in the plans, the Contractor shall furnish and

install test piles of the sizes, types, and lengths at the locations shown on the plans. The number of test piles may be increased or decreased by the Bridge Engineer as field conditions warrant. If determined by the En gineer to be necessary, test piles shall be extended, built-up, or spliced and in the case of steel piles driven further if deemed necessary, to the depths established by the Bridge Engineer. Similarly, the Contractor may be required to drive test piles below cut-off and extended as necessary.

803.03.1 12--Protection of Existing Structures. When the plans require piling to be

driven within close proximity to existing stru ctures, utilities, or recently placed concrete, the Contractor shall take all r easonable precautions to prevent damage to such structures. This shall include newly constructed bridge components. If not otherwise provided for in the plans, the Contractor shall be solely responsible for taking measures to prevent damage to existing structures resulting from pile driving operations. These measures shall include, but are not limited to, monitoring and controlling the vibrations resulting from pile driving activities. Driving of piling wi thin 30 feet of recently placed concrete will not be permitted unless the concrete in that structure has attained a compressive strength of 2500 psi, as determined by cylinder tests, or maturity meter probe when maturity meter readings indicate that the required concrete strength is achieved. Test samples shall be prepared and tested by the Department from material repres entative of the recently constructed structure Hydraulic Jac k The minimum opening between the top of the pile and the reaction frame shall be approximately 14” plus the height of the jack. For piling greater than 24” in dia. (width) additional opening may be required. Pile 1” Steel Bearing Plates Measuring FrameReaction Frame 10.75” dia. Load Cell Dial Gauges (To Be Supplied by Department) and cured in conditions similar to the structure. Based upon observations, the Engineer may adjust this distance accordingly.

803.03.2 Drilled Shafts.

803.03.2 1--Submittals.

803.03.2 1.1--Qualification of Contractor. The person(s) or firm directing the work

described in this specification shall be knowledgeable of drilled shaft installation procedures and shall have installed drilled shafts of both diameter and length similar to those shown in the plans in accordance with the following minimum experience requirements:

803.03.2 2--Trial Shaft Construction. The Contractor shall dem onstrate the adequacy of

the methods and equipment during construction of an out of position trial shaft. This trial shaft shall be positioned as far as practical fr om the production shafts, in the position shown on the plans or as directed by the Engineer, and shall be drilled to the minimum tip elevation as required on the plans. When shown on the plans, the reaming of bells at specified trial shafts will be required to establish the feasibilit y of belling in a specific soil strata. Failure to demonstrate the adequacy of the Contractor's methods and equipment to construct the trial shaft shall be cause for the Engineer to require alterations in equipment and/or method by the Contractor, to eliminate unsatisfa ctory results. Backfilling of unsuccessful excavations and any additional trial shafts requi red to demonstrate the adequacy of altered methods of construction or equipment shall be performed by the Contractor at no additional cost to the State. Once the Contractor has completed the excavation for the trial shaft to the satisfaction of the Engineer, the Contract or shall set the reinforcement and pour the concrete to finish construction of the trial shaf t. This shall be demonstration that the entire plan for drilled shaft construction is satisfactory. Failure to successfully construct the trial shaft shall be cause for rejection of the trial shaft, and shall be reason for the Engineer to require alterations necessary to eliminate un satisfactory results. Additional trial shafts necessary to demonstrate correc tion of deficiencies shall be at the Contractor's expense. If differing soil conditions require two (2) or more methods for construction of production shafts, said methods shall be demonstrated by trial shaft prior to construction of any production shaft. After the successful trial shaft has been comp leted, the Contractor shall submit in writing for review the successful methods and equipm ent used. This submittal, once reviewed, will serve as the approved method of construc tion for all the production shafts covered by that successful trial shaft. Once approval has been given to construct production shafts, no changes will be permitted in the methods, equipm ent, drilled shaft superintendent, or driller from those used during the construction of th e trial shaft without wr itten approval of the Engineer. Trial shafts shall be cut off two (2) feet below finish grade or two (2) feet below the mud line and left in place. The portions of the shafts cut off and removed shall remain the property of the Contractor. The disturbed areas in the vicinity of the trial shaft shall be restored as nearly as practical to their original condition.

803.03.2 3--Construction Methods and Equipment.

803.03.2 3.1--General.

803.03.2 3.1.1--Protection of Existing Structures. When the plans require drilled shaft

excavations within close proximity to existing structures or utilities, the Contractor shall take all reasonable precautions to prevent damage to such stru ctures. This shall include newly constructed shafts. If not otherwise provided for in the plans, the Contractor shall be solely responsible for evaluating the need for, design of, and providing all reasonable precautionary features to prevent damage. These measures shall include, but are not limited to, selecting construction methods and procedures that will prevent caving of the shaft excavation, and monitoring and controlling the vibrations from construction activities, including the driving of casings, dr iving of sheeting, or from blasting, when permitted. Advancing an uncased drilled shaft excavation or the use of a vibratory hammer to install casings within three times the diameter of a newly constr ucted shaft will not be permitted unless the concrete in that shaft has attained a compressive strength of 2500 psi, as determined by cylinder tests, or maturity meter probe when maturity meter readings indicate that the required concrete strength is achieved. Test samples shall be prepared and tested by the Department from material representative of the upper mass of the newly constructed shaft and cured in conditions similar to the drilled shaft. Based upon observations, the Engineer may adjust this dist ance accordingly. During shaft construction, the Contractor shall take into account and make provisions for vibrations caused by activities other than the Contractor’s, such as adjacent traffic. If a maturity meter probe is used, it shall be located in the upper portion of the drilled shaft concrete. Procedures for using the maturity meter and developing the strength/maturity relationship shall follow the requirements of AASHTO T 325 and ASTM C 1074 specifications. Technicians using the maturity meter or calculating strength/maturity graphs shall be required to have at least two hours of training prior to using the maturity equipment. The training shall be approved by the Department. Such structures shall be monitored for settlement in an approved manner, recording elevations to 0.01 foot. The number and location of monitoring points shall be as approved by the Engineer. Elevations shall be taken before construction begins, during the driving of any required casings, and during ex cavation as directed by the Engineer. When shown on the plans, or as directed by the Engineer, the Contractor shall monitor and record vibration levels during the driving of casings, sheeting, or during blasting operations. Vibration monitoring equipment shall be capable of detecting particle velocities of 0.1 inch/second or less. At any time the Contractor detects settlement of 0.03 foot, vibration levels reaching 1.5 inches per second, or damage to the structur e, the Contractor shall immediately stop the source of vibrations, backfill the excavation, and contact the Engineer for instructions.

803.03.2 3.1.2--Construction Sequence for Site Preparation. Excavation to the plan

footing elevation, if required, shall be comp leted before shaft construction begins. Any disturbance to the footing area caused by shaft installation shall be repaired by the Contractor prior to the footing pour. When drilled shafts are to be installed in conjunction with embankment placement, the Contractor shall construct the drilled shafts after placement of the embankment material.

803.03.2 3.1.3--General Methods and Equipment. The Contractor shall perform the

excavations required for the shafts and be ll footings, through whatever materials encountered to the dimensions and elevations shown on the plans, or otherwise required by the specifications, at no additional cost to the State. The Contractor's methods and equipment shall be suited for the intended purpose and the materials encountered. Drilled shafts shall be constructed by the dry method, wet method , casing method, or permanent casing method, as necessary to pr oduce a sound, durable, concrete foundation free of defects. The permanent casing method shall be used only when required by the plans or authorized by the Engineer. When the plans describe a particular method of construction, this method shall be used unless otherwise permitted by the Engineer. The Engineer may permit an alternate method than designated on the plans, only after successful construction of an out of position trial shaft. Wh en the plans do not describe a particular method, the Contractor shall utilize a method on the basis of its suitability to the site conditions. Blasting shall only be permitted if specifically stated on the plans or approved by the Engineer. Once approval is given to construct production shafts, no changes will be permitted in the methods or equipment from those used in constructing the accepted trial shaft without written approval of the Engineer.

803.03.2 3.2--Dry Construction Method. The dry construction method shall be used only

at sites where the groundwater level and soil conditions are suitable to permit construction of the shaft in a relatively dry excavation, an d where the sides and bottom of the shaft may be visually inspected by the Engineer prior to placing the concrete. The dry method consists of drilling the shaft excavation, plac ing the reinforcing cage, and concreting the shaft in a relatively dry excavation. The dry construction method shall be us ed only when the trial shaft excavation demonstrates that: concrete can be placed with less than three (3) inches of accumulated water in the bottom of the shaft; the sides and bottom of the hole remain stable without caving, sloughing, or swelling over a two-hour period immediately following completion of the excavation; and any loose material and excess water can be satisfactorily removed prior to inspection and prior to concrete placement.

803.03.2 3.3--Wet Construction Method. The wet construction method shall be used at

all sites where it is impractical to provid e a dry excavation for placement of the shaft concrete. The wet construction method consists of drilling the shaft excavation below the water table, keeping the shaft filled with water or mineral sl urry, desanding or cleaning the slurry, final cleaning of the excavation by means of a bailing bucket, air lift, submersible pump or other approved devices, and placing the rebar cage and the shaft concrete, with a tremie or concrete pump beginning at the shaft bottom, which displaces the water or slurry as the shaft is concreted. Temporary surface casings shall be provided to aid shaft alignment and position and to prevent sloughing of the top of the shaft, except when the Contractor demonstrates to the satisfaction of the Engin eer that the surface casing is not required. Where drilled shafts are located in open water areas, the shafts shall be constructed by the wet method using casings extending from above the water elevation into the ground to protect the shaft concrete from water action during placement and curing of the concrete. The casing shall be installed in a manner that will produce a positive seal at the bottom of the casing so that there is no intrusion or extr usion of water or other materials into or from the shaft excavation. Casings for this app lication may include multiple casings, temporary casings, and/or designed permanent casings. The wet construction method may be used in combination with the dry method and temporary or permanent casing methods.

803.03.2 3.4--Casing Construction Method. The casing construction method may be

used at sites when the dry or wet construction methods are inadequate to prevent hole caving or excessive deformation of the hole. In this method, the casing may be either placed in a predrilled hole if no caving, swelling, or yielding occurs, or advanced through the ground by twisting, driving, or vibration before being cleaned out. When a formation is reach ed that is nearly impervious, a casing shall be placed in the hole and seated in the nearly impervious format ion. Drilling may pro ceed as with the dry method to the projected depth. If seepage occurs at this point, temporary casing may be advanced further to create the dry condition. In the event seepage conditions prevent use of the dry method, excavation shall be completed using wet methods. The placement of the concrete shall proceed as with the wet or dry method, except that the casing shall be withdrawn after the concrete is placed. When caving soils occur near the ground surface and/or if the top of the concrete for the drilled shaft is below the gro und surface, the Contractor sh all set a suitable temporary removable surface casing. The minimum surface casing length shall be the length required to prevent caving of the surface soils and to aid in maintaining shaft position and alignment. Predrilling with slurry and/or overreaming to the outside diameter of the casing may be acceptable if required to install the surface casing at some sites. Where drilling is through materials having a tendency to cave, the drilling shall be advanced by drilling in a mineral slurry. In the event that a caving layer or layers are encountered that cannot be controlled by slurry, the Contractor shall install temporary removable casing through such caving layer or layers. Overreaming to the outside diameter of the casing may be required. However, the final dimensions of the drilled shaft shall not be altered to accommodate these construction practices unless approved by the Engineer. The Contractor shall take whatever steps th at are required to prevent caving during shaft excavation including installation of deeper casings. If the Contractor elects to remove a casing and replace it with a longer casing th rough caving soils, the Contractor shall adequately stabilize the excavation with slurry or backfill the excavation. Other approved methods that will control the size of the ex cavation and protect the integrity of the foundation soils may be used to excavate through caving layers.

803.03.2 3.5--Permanent Casing Method. The permanent casing method shall be used

when required by the plans. In this method, a casing is driven to the prescribed depth before excavation begins. If full penetration cannot be attained, the Contractor may excavate material from inside the casing and the casing may be driven again until reaching the desired penetration. In some cases overreaming to the outside diameter of the casing may be required before driving the casing. The casing shall be cut off at the prescribed elevation upon reaching the proper construction sequence, and the remainder of the casing is left in place. 803.03.2.3.6--Excavation and Drilling Equipment. The excavation and drilling equipment shall have adequate capacity including power, torque, and down thrust to excavate a hole of both the ma ximum diameter and to a depth 20 percent greater than the longest shaft shown on the plans. The excavation and overreaming tools shall be of adequate design, size, and strength to perform the work shown on the plans or described herein. When the material encountered cannot be drilled using conventional earth augers with soil or rock teeth, drill buckets, and/or underreaming tools, the Contractor shall provide special drilling equipment including but not limited to: rock core barrels, rock tools, air tools, blasting materials, and other equipment as necessary to construct the shaft excavation to size and the depth required. Approval of the Engineer is required before excavation by blasting is permitted. Sidewall overreaming shall be required when the sidewall of the hole is determined by the Engineer to have either so ftened due to excavation meth ods or delays in excavation completion, swelled due to delays in concreting, or degraded because of slurry cake build-up. Overreaming thickness shall be a minimum of one-half inch (½”) and a maximum of three inches (3”) be yond the shaft radius. Overream ing may be accomplished with a grooving tool, overreaming bucket, or other approved equipment. The thickness and elevation of sidewall overreaming shall be as directed by the Engin eer. The Contractor shall bear all costs associated with both side wall overreaming and additional shaft concrete placement.

803.03.2 3.7--Excavations.

803.03.2 3.7.1--General. Shaft excavations shall be made at locations and to the top of

shaft elevations, estimated bo ttom of shaft elevations, shaft geometry and dimensions shown in the plans. The Contractor shall extend drilled shaft tip elevations when the Geotechnical Engineer determin es that the material encountered during excavation is unsuitable and/or differs from that anticipat ed in the design of the drilled shaft. The Contractor shall maintain a drilling log duri ng shaft excavation. The log shall contain information such as: the description and approximate top and bottom elevation of each soil or rock strata, seepage or groundwater, and remarks. Th ree (3) copies of the final Contractor's log shall be furnished to the Engineer with a copy to the Geotechnical Engineer at the time the drilled shaft is completed and accepted. When shown on the plans, bells shall be excavated to form the height and bearing area of the size and shape shown. The bell shall be excavated by mechanical methods. Any drilled shaft concrete over the theoretical amount required to fill any excavations for the bells and shafts dimensioned on the plans shall be furnished at no additional cost to the State. The Contractor shall not permit workmen to en ter a shaft excavation for any reason unless

803.03.2 3.7.2--Obstructions. Surface and s ubsurface obstructions at drilled shaft

locations shall be removed by the Contractor. Such obstructions may include man-made materials such as old concrete foundations and natural materials such as boulders. Special procedures and/or tools shall be employed by the Contractor after the hole cannot be advanced using conventional augers fitted with soil or rock teeth, drilling buckets and/or underreaming tools. Such special procedures/tools may include, but are not limited to, chisels, boulder breakers, core barrels, air tools, hand excavation, temporary casing, and increasing the diameter of the hole. Blasting shall not be permitted unless specifically approved in writing by the Engineer. Drilling tools that are lost in the excavation shall be promptly removed by the Contractor at no cost to the State. All costs due to lost tool removal shall be borne by the Contractor including, but not limited to, costs associated with hole degradation due to removal operations or the time the hole remains open.

803.03.2 3.7.3--Exploration. When directed by the Engineer , the Contractor shall take

soil samples or rock cores to determine the character of the material directly below the completed shaft excavation. The soil samples shall be extracted with a standard penetration test split spoon sampler or undisturbed sample (Shelby) tube. Rock cores, if required, shall be cut with an approved double or triple tube core barrel to a minimum of five (5) feet below the bottom of the drilled shaft excavation at the time the shaft excavation is approximately complete. Rock core, undisturbed tube, and/or standard penetration test samples shall be measured, visually identified, and described on the Contractor's log. The samples shall be placed in suitable containers , identified by shaft loca tion, elevation, and project number, and delivered with the Contractor's field log to the Engineer within 24 hours after the exploration is completed. Th e Engineer will inspect the samples or cores and determine the final depth of required excavation based on the evaluation of the material.

803.03.2 3.7.4--Excavation Completion. Concrete placement must begin within two (2)

hours of completion of sh aft excavation. If the drilled shafts are five (5) feet in diameter or larger and in excess of sixty (60) feet in length, the elapsed time from completion of the drilled shaft excavation until beginning of concrete pl acement may extend past two hours provided the excavation remains stable and the extended time is demonstrated on the trial shaft. Completion of shaft excavation is defined as the time at which the specified tip elevation is initially achieved. Before concrete placement begins, bottom cleaning operations, any necessary slurry desanding, and placement of the reinforcing steel must be completed. These operations are included in the two hour time limit. If it becomes apparent, as the excavation of the shaft is nearing completion, that it will not be feasible or possible to place concrete within the specified limit, the Contractor shall halt excavation operations a minimum of five (5) feet above the specified tip elevation. In the event that the wet construction method is being used, the slurry should be desanded at this point so that the remaining excavation will not cause the slurry to be too heavily contaminated and delay concrete placement due to final desanding operations. In no case shall any excavation within the be aring zone(s) be allowed to remain open and idle for more than 24 hours. The bearing z one(s) are those soil strata located below the scour line, in the case of hydr aulic structures, or five feet (5’) below the ground line, whichever is greatest in depth. In no instance shall any uncased excava tion, except for trial shafts, be allowed to remain open and idle for more than 24 hours. For partially completed excavations that stand idle for more than six (6) hours but less than 24 hours, sidewall overreaming may still be required by the Engineer. If completion of shaft excavation has been achieved and concrete placement has not begun within the specified limit, the Contractor shal l backfill and/or stabilize the excavation. The Engineer shall then direct the Contractor as to the additional shaft excavation that will be required to produce a sound drilled shaft due to shaft wall and bottom degradation. The cost of the additional excavation, concrete, reinforcing steel, and other incidentals will be borne by the Contractor at no additional cost to the State.

803.03.2 3.7.5--Casings.

803.03.2 3.7.5.1--General. Casings shall be steel, smooth, clean, watertight, and of ample

strength to withstand both handling and driving stresses and the pressure of both concrete and the surrounding earth materials. The outsid e diameter of casing shall not be less than the specified size of the shaft. No extra comp ensation will be allowed for concrete required to fill an oversized casing or oversized exca vations. All casings, except permanent casing, shall be removed from the shaft excavation. Any length of permanent casing installed below the shaft cutoff eleva tions shall remain in place. When the shaft is to extend above the ground or through a body of water, the portion exposed above the ground or through a body of water may be formed with removable casing, except when permanent casing is sp ecified. Removable casing shall be stripped from the shaft in a manner that will not damage the concrete. Casings can be removed when (a) the concrete is cured for a full 72 hours; (b) the shaft concrete is not exposed to salt water or moving water for seven (7) days; and (c) the concrete reaches a compressive strength of at least 2500 psi as determined from concrete cylinder tests prepared and tested by the Department. The concrete cylinders will be prepared from material representative of the upper 10% mass of the newly constructed shaft and cured in conditions similar to the drilled shaft.

803.03.2 3.7.5.2--Temporary Casing. All subsurface casing shall be considered

temporary unless specifically shown as perm anent in the contract documents. All temporary casing shall be removed. Tele scoping, predrilling with slurry, and/or overreaming to beyond the outside diameter of the casing may be required to install the casing. When temporary casing larger than called for on the plans is used for telescoping or overreaming, no additional compensation will be made. If the Contractor elects to remove a casing and substitute a longer or larger diameter casing through caving soils, the excavation shall be either stabilized with slurry or backfilled before the new casing is installed, as directed in Subsection 803.03.2.3.4. Other methods, as approved by the Engineer, may be used to control the stability of the excavation and protect the integrity of the foundation soils. When temporary casings that are to be removed become fouled or bound in the shaft excavation and cannot be practically removed, and concreting has not yet begun, the Engineer may direct that the shaft excavation be drilled deeper to compensate for the loss of capacity due to the presence of the casing. No additional compensation will be paid for the casing left in the excavation. No additional length of shaft will be paid for beyond the current depth of excavation or the plan tip elevation of the production shaft, whichever is lower. Temporary casings that become bound or fouled during concreting of the shaft and that cannot be practically removed before the concrete begins to set up, shall constitute a defect in the drilled shaft. When the Engineer, in writing, notifies the Contractor of a defective shaft, the Contractor shall be responsible for improving such defective shafts to the satisfaction of the Engineer. Improvements may consist of, but are not limited to, removing the shaft concrete and extending the shaft de eper to compensate for loss of frictional capacity in the cased zone, providing straddle sh afts to compensate for capacity loss, proof load testing or providing replacement shafts. All corrective measures, including redesign of footings or drilled shaft caps, shall be perf ormed to the satisfaction of the Engineer by the Contractor without either additional compen sation or extension of Contract Time. No compensation will be paid for casing remaining in place. Any redesigns submitted must be approved in writing by the Bridge Engineer. Temporary casing extraction shall be slow and unif orm, pulling along the axis of the shaft. The elevation of the concrete in the casing sh all be maintained high enough to displace the drilling slurry between the outside of the casing and the edge of the hole as the casing is removed. Temporary casings shall be remove d while the concrete remains workable. No temporary casings will be removed if the concre te slump is less than four (4) inches. Should this condition occur, the shaft will be c onsidered defective, a nd corrections to the situation shall be as described above. Special casing systems may be used in open water areas, when approved and must be designed to permit removal after the concrete has hardened. Special casings shall be designed so that no damage occurs to the drilled shaft concrete during their removal. Any defects either cosmetic or structural that are apparent after removal of the casing or are due to the removal of the casing shall be repaired to the satisfaction of the Engineer at no additional cost to the State. In the event that permanent casing is not speci fied in the plans, and the Contractor elects to use a temporary casing and leave it in place, it shall be cut off at a maximum of 12 inches above the low water elevation as shown on the plans, or painted. Written approval from the Engineer is required in this event, and payment for the temporary casing left in place will be at the contract bid price for temporary casing. 803.03.2.3.7.5.3--Permanent Casings. Permanent casing shall be used when shown on the plans. The casing shall be continuous between top and bottom elevations prescribed on the plans or as directed by the Engineer. Exterior surfaces of pe rmanent casing shall be painted in accordance with the plans unless othe rwise noted. After installation is complete, the permanent casing shall be cu t off at the prescribed eleva tion and the shaft completed. In general, permanent casing shall not be placed in an overreamed shaft hole.

803.03.2 3.8--Slurry. Mineral slurries shall be employed when slurry is used in the drilling

process, unless other drilling fluids are appr oved in writing by the Engineer. The slurry shall have both a mineral grain size that will remain in suspension and sufficient viscosity and gel characteristics to transp ort excavated material to a suitable screening system. The percentage and specific gravity of the material used to make the suspension shall be sufficient to maintain the stability of the excavation and to allow proper concrete placement. During construction, the level of th e slurry shall be maintained at a height sufficient to prevent caving of the hole. In the event there is a sudden, significant loss of slurry within the drilled shaft excavation, the construction of the drilled shaft shall be stopped until a method to stop sl urry loss or an alternate c onstruction procedure has been approved by the Engineer. Mineral slurry shall be premixed thoroughly w ith clean, fresh water, and an adequate time (as prescribed by the mineral manufacturer) shall be allotted for hydration, prior to introduction into the shaft excavation. Slurry tanks of adequate capacity will be required for slurry circulation, storage, and treatment. No excavated slurry pits will be allowed in lieu of slurry tanks, without the written permission of the Engineer. Desanding equipment shall be provided by the Contractor as necessary to control slurry sand content to less than two percent (2%) by volume at any point in the borehole. Desanding will not be required for setting sign posts or lighting mast foundations unless shown on the plans. The Contractor shall take all steps necessary to prev ent the slurry from "setting up" in the shaft. Such methods may include, but are not limited to: agitation, circulation, and/or adjusting the properties of the slurry. Disposal of all slurry shall be performed offsite in suitable areas by the Contractor, and subject to all environmental regulations pertaining to slurry disposal. Control tests using suitable apparatus shall be carried out on the mineral slurry mixture by a qualified individual or qualified professional testing laboratory approved by the Engineer. Tests to be conducted will be density, sand content, viscosity, and pH. The acceptable range of values for those physical properties is as follows: MINERAL SLURRY Sodium Montmorillonite (Commercial Bentonite) Acceptable Range of Values Property At Time of Slurry In Hole at Time of Test Units Introduction Concreting Method Density, pcf 64.3** - 69.1** 64.3** - 75.0** Density Balance Viscosity, 28 - 45 28 - 45 Marsh Cone seconds/quart pH 8 - 11 8 - 11 pH paper pH meter **Increase by 2 pcf in salt water Notes: a. Tests should be performed when th e slurry temperature is above 40 degrees Fahrenheit.

803.03.2 4--Excavation Inspection. The Contractor shall prov ide equipment for checking

the dimensions and alignment of each drilled shaft excavation. The dimensions and alignment shall be determined by the Contract or in the presence of the Engineer or the Engineer’s inspector. Final shaft depths shall be measured with a weighted tape or other approved methods after final cleaning. Unless otherwise stated on the plans, a minimum of 50 percent of the base of each shaft shall have less than 1/2 inch of sediment at the time of placement of the concrete. Shaft cleanliness will be determined by the Engineer, by visual inspection for dry shafts, or other meth ods deemed appropriate to the Engineer for wet shafts. In addition, for dry excavations, the maximum depth of water shall not exceed three (3) inches prior to concrete pour. SLURRY SAMPLER The sampler consists of three components:

803.03.2 5--Construc tion Tolerances. The following construction tolerances apply to

drilled shafts unless otherwise stated in the contract documents:

803.03.2 6--Reinforcing Steel Construction and Placement. The reinforcing steel cage,

consisting of longitudinal bars, ties, cage s tiffener bars, spacers, centralizers, and other necessary appurtenances, shall be completely assembled and placed as a unit immediately after the shaft excavation is inspected and accepted, and prior to concrete placement. Details of reinforcing steel will be as shown in the plans. The reinforcing steel in the shaft shall be double-wire tied at all junctions and supported so that the reinforcing steel will remain within allowable tolerances given in Subsection

803.03.2 5. Stiff tie wire may be required for long reinforcing steel cages. Free-rolling

concrete centralizers or other approved noncorrosive rolling centralizer devices shall be used at sufficient intervals. The centralizers shall be attached to the reinforcing steel cage near the bottom, and at intervals not exceeding 10 feet up the shaft for shaft lengths less than 60 feet, and intervals not exceeding seven (7) feet for shaft lengths greater than 60 feet, to ensure concentric spacing for the entire cage length. Centralizers shall be constructed of approved material equal in quality and durability to the concrete specified for the shaft. The centralizers shall be of adequate dimension to insure a minimum five (5) inch annular space between the outside of the re inforcing cage and the side of the excavated hole. Approved cylindrical f eet (bottom supports) shall be provided to ensure that the bottom of the cage is maintained the proper distance above the base. The elevation of the top of the steel cage sha ll be checked before and after the concrete is placed. If the rebar cage is not maintained w ithin the specified tolera nces, corrections shall be made by the Contractor to the satisfaction of the Engineer. No additional shafts shall be constructed until the Contractor has modified the rebar cage support in a manner satisfactory to the Engineer. If the bottom of the excavated shaft elevation is lower than the bottom of the shaft elevation shown on the plans, all reinforcement required in the upper portion of the shaft shall be achieved by splicing the additional length at the bottom of the cage, to avoid congestion in the upper portion of the shaft.

803.03.2 7--Concrete Placement.

803.03.2 7.1--General. Drilled Shaft concrete shall meet the requirements in Section 804.

Concrete placement during cold weather shall be allowed when ambient air conditions are at or expected to drop below 40°F, but protection of the fresh concrete shall be in accordance with the provisions st ated in Sections 804 and 50 1. The Contractor shall assume all responsibility for protection of fresh concrete in cold weather. Concrete shall be placed as soon as possible after reinforcing steel placement. Concrete placement shall be continuous from the bottom to the top elevation of the shaft. Concrete placement shall continue after the shaft excavation is full un til good quality concrete is evident at the top of the shaft. Concrete shall be placed either through a tremie, concrete pump or free fall. Free fall placement shall require prior written approval of the Engineer and shall be restricted for use in dry excavations only. For tremied or pumped concrete, the elapsed time from the beginning of concrete placement in the shaft to the co mpletion of the placement shall not exceed four (4) hours, except as noted below. Retarders and/or water reducers in the concrete mixture shall be adjusted as approved for the conditions encountered on the project, so that the concrete remains in a workable plastic state throughou t the four-hour placement limit. A workable plastic state is defined as a minimum slump of four inches (4”) existing everywhere within the concrete shaft after placement has been completed. Prior to concrete placement, the Contractor shall provide test results meeting the requirements of Subsection 804.02.10 and a slump loss test per the requirements in Subsection 804.02.10.3.1. The Contractor may request a longer placement time, provided a concrete mixture is supplied that will maintain a slump of four inches (4”) or greater over the longer placement time, as demonstrated by slump loss tests. In the event that free-fall concrete placement is approved and used, the 4-inch slump in four hours requirement will be waived. The Contractor shall place the concrete w ithin the approved time and temperature limitations determined by the trial mix demonstration. Before the casing is withdrawn, the fresh concre te shall be at such a level that the fluid trapped behind the casing is displaced upward. As the casing is withdrawn, care shall be exercised to maintain the level of concrete within the casing so that the fluid trapped behind the casing is displaced upward out of the shaft excavation without mixing with or displacing the shaft concrete.

803.03.2 7.2--Tremies. Tremies used for concrete placement in either wet or dry

excavations shall consist of a tube of suffici ent length, weight, and diameter to discharge concrete at the shaft base elevation. The tremie shall not contain aluminum parts that will have contact with the concrete. The tremie inside diameter shall be at least six (6) times the maximum size of aggregate used in the concrete mix but shall not be less than 10 inches. The inside and outside surfaces of the tremie shall be clean and smooth to permit both flow of concrete and unimpeded withdrawal during concreting. The wall thickness of the tremie shall be adequate to prevent crimping or sh arp bends that restrict concrete placement. The tremie used for wet excavation concrete placement shall be watertight. Underwater placement shall not begin until the tremie is placed at the bottom of the excavation. Valves, bottom plates, or plugs may be used only if concrete discharge can begin within one tremie diameter of the base. Plugs and plates shall either be removed from the excavation or be of a material, approved by the Engineer, that will not cause a defect in the shaft if not removed. The discharge end of the tremie shall be constructed to permit the free radial flow of concrete during placem ent operations. The tremie discharge end shall remain at the excavation bottom as long as possible, an d thereafter be immersed at least two shaft diameters but not less than 10 feet in concrete at all times after starting the flow of concrete. The flow of concrete shall be continuous. The concrete in the tremie shall be maintained at a positive pressure differential at all times to prevent water or slurry intrusion into the shaft concrete. If, at any time during the concrete pour in a wet excavation, the tremie line orifice is removed from the fluid concrete column and discharges concrete above the rising concrete level, the shaft shall be considered defective. In such case, the Contractor shall remove the reinforcing cage and concrete, complete all necessary sidewall removal directed by the Engineer and repour the shaft. All costs of replacement of defective shafts shall be the responsibility of the Contractor.

803.03.2 7.3--Pum ping Concrete. Concrete pumps and lines may be used for concrete

placement in either wet or dr y excavations. All pump lines shall have a minimum 5-inch diameter and be constructed with watertight joints. The use of aluminum pipe as a conveyance for the concrete will not be perm itted. Concrete placement shall not begin until the pump line discharge orifice is at the bottom of the excavation. For wet excavations, a plug or similar device shall be used to separate the concrete from the fluid in the hole until pumping begins. The plug shall either be removed from the excavation or be of a material, approved by the Engineer, that will not cause a defect in the shaft if not removed. The discharge orifice shall remain at least tw o shaft diameters but not less than 10 feet below the surface of the fluid concrete at all ti mes after starting the flow of concrete. When lifting the pump line during concreting, the Contractor shall temporarily reduce the line pressure until the orifice has been repositioned at a higher level in the excavation. If, at any time during the concrete pour, the pump line orifice is removed from the fluid concrete column and discharges concrete above the rising level, the shaft shall be considered defective. In such case, the Cont ractor shall remove the reinforcing cage and concrete, complete all necessary sidewall removal directed by the Engineer and re-pour the shaft. All costs of replacement of defec tive shafts shall be the responsibility of the Contractor.

803.03.2 7.4--Free Fall Method. Placement of concrete by the free fall method will be

permitted only when approved in writing by the Engineer. Approval of concrete placement by the free fall method shall be conti ngent upon the following conditions:

803.03.2 8--Drilled Shaft Load Tests. The methods required for the load testing of drilled

shafts shall be Static and/or Static with Special Instrumentation. Load testing of drilled shafts shall be completed before construc tion of any production drilled shafts, and the results used by the Bridge Engineer to determ ine the drilled shaft lengths given on the order list. The method, number, and locations of load tests shall be as shown on the plans or as designated by the Engineer. After completion of any load test, the order list providing the final production lengths will be provided within two weeks of receiving th e load test results. The production shaft lengths provided by the Bridge Engineer may differ from the individual shaft lengths shown on the plans. Requests for adjustment to the contract due to changes in shaft lengths shall be subject to the provisions of Subsectio n 104.02.1. Before any consideration will be given for an adjustment to the contract, it must be determined that a significant change in the character of the wo rk has occurred.

803.03.2 8.1--Static Load Tests. Static load testing shall not begin until the concrete has

attained a compressive strength of 3000 psi as determined from cylinder tests, or maturity meter probe in accordance with Subsection 803. 03.2.3.1.1. If a matu rity meter probe is used, it shall be located in the last conc rete placed. During the curing time, no other construction or operations that will induce excessive vibration levels, as previously discussed, shall be performed. Static axial load tests shall be performed by personnel of the Department’s Geotechnical Branch assisted by the Contractor’s personnel using the procedures as described in ASTM D 1143, quick test method. No weighted platforms to totally supply the axial load are allowed. The Contractor shall be responsi ble for furnishing the following:

803.03.2 8.2--Load Testing of Drilled Shafts With Special Instrumentation.

803.03.2 8.2.1--General. When designated on the plans, a dedicated test shaft shall be

constructed as detailed in the plans with instrumentation and hydraulic jack(s) cast in the concrete of the drilled shaft. The Contractor will be required to furnish all materials, equipment, labor, and incidentals necessary fo r conducting the load test and reporting the results. The Contractor shall subcontract the instrumenting, conducting, and reporting of the load test to the company supplying the instrumentation with the cost included in the contract unit price for test shaft. No reaction systems and extra drilled shaft insta llations such as anchor shafts are required for conducting the load test. The load test is a non-destructive test, and if the test shaft designated on the plans is a production shaft, it shall be left in a condition suitable for use as a production shaft in the finished structure.

803.03.2 8.2.2--Materials. When called for in the plans, instrumentation shall be supplied

to meet the requirements set forth in the plans. Instrumentation required in the plans is subject to prior approval by the State Geotechnical Engineer. Additional equipment that may be required is as follows:

803.03.2 8.2.3--Equipment. The Contractor shall supply any additional equipment

required to install the testing instrumentation, conduct the load test, and remove the load test apparatus. If the test shaft is to become a production shaft at the conclusion of the test, the Contractor shall restore the shaft to a condition suitable for us e in the finished structure. This equipment includes, but is not limited to:

803.03.2 8.2.4--Procedure. The test shaft shall be constructed by the shaft construction

technique approved by the Engineer after trial sh aft construction. The test shaft shall then be constructed in accordance with the plans and at the direction of the Engineer. The instrumentation shall be assembled and made ready for installation under the direction of the instrumentation supplier, in a suitable area that is adjacent to the test shaft. When a reinforcing cage is required for the test shaft, the instrumentation shall be placed as directed in the plans. When the test shaft excavation has been completed and accepted by the Engineer, the Contractor shall then install the instrumentation and, if required, the reinforcing cage assembly in the test shaft under the direction of the Engineer. The Contractor shall use the utmost care in handling the reinforcing cage and test equipment assembly so as not to damage the instrumentation during installation. After the installation of the instrumentation, the test shaft shall be concreted in the manner approved from the trial shaft construction. Lo ad testing shall not begin until the concrete has attained a compressive strength of 3000 psi as determined from cylinder tests. During the curing period, no other construction or operations that will induce excessive vibration levels shall be performed. After completion of the load test, and at the direction of the Engineer, the Contractor shall remove any items, including equipment and material that are not to be a part of the finished structure. The Contractor shall supply the Engineer with six (6) copies of the final load test report.

803.04 Method of Measurement.

803.04.1 Test Piles. Test piles will be measured per each complete-in-place. Piles

measured as test piles will not be included in the measurement of pay footage for permanent piles. Test piles constructed in accordance with the lengths indicated on the plans and that are required to be extended or built up will be me asured as a percentage, calculated by dividing the sum of the plan length plus the length of the ordered extension or build-up, by the plan length. Splices required for the extension(s) will not be measured for payment. No measurement for payment will be made for cut-off of a test pile.

803.04.2 Conventional Static Pile Load Tests. Conventional static pile load tests will

be measured by the actual number of static load tests conducted on either a test pile or permanent production pile in accordance with these specifications. In the event a pile is reloaded in accordance with these specifications , the reloading will be measured for payment as 50 percent of a separate conventional static pile load test.

803.04.3 Pile Shoes . Pile shoes of approved design, ordered and used, will be measured

and paid as set out in Subsection 803.05.3. 803.04.4--Piling. Piling, exclusive of those measured as test piles, will be measured by the linear foot for each class and size of pilin g, furnished and installed in accordance with the lengths shown on the plans or as approved by the Department’s Bridge Engineer. Cut-offs for each individual pile will be measur ed and deducted as set forth in Subsection

803.04.5 Pile lengths in excess of those shown on the plans or approved by the Bridge Engineer will

not be measured for payment unless such additional lengths below cut-off are approved in writing by the Bridge Engineer for incorporation in the structure.

803.04.5 Cut-Off. The summation of all cut-offs sha ll be deducted at 40 percent to

determine the length for payment of in-place permanent piling. The summation of all cut-offs for pile lengths in excess of those shown on the plans or approved by the Bridge Engineer will be deducted at 100 percent to determine the length for payment of in-place permanent piling. An allowance will be made for prestressed conc rete piling cut-offs in accordance with the provisions of Subsection 803.05.5. Cut-offs shall be measured for payment per each for each pile requiring cut-off. All piling cut-offs shall become the property of and shall be disposed of by the Contractor.

803.04.6 Extensions or Build-Ups. Extensions or build-ups will not be measured for

payment as such, but will be included in the length of piling remaining in the finished structure. In determining the amount to be included in piling footage, no allowance will be made for cut-offs necessary to accomplish the extensions or build-ups.

803.04.7 Falsework and Defective Piles. No allowance will be made for furnishing or

driving of falsework piles, for piles driven out of place, for defective piles, or for piles damaged by handling or driving. 803.04.8--Splices. Splices necessary for extensions or build-ups on bearing piles will be measured by the linear foot. Fo r prestressed concrete piles, the number of linear feet will be determined by allowing seven linear feet of piling for each splice. For other piles, the number of linear feet will be determined by a llowing four linear feet of piling for each splice. The total number of linear feet of piling to be paid for shall be determined by adding seven feet or four feet, as applicable, to the net length of piling for each splice in place in the finished structure. No measurement or payment will be made for splices except those made at the direction and under the supervis ion of the Engineer.

803.04.9 Pre-formed Pile Holes. Pre-formed pile holes, when included as a pay item on

the plans, will be measured by the linear foot. For trestle type bents, the footage for each hole will be determined by subtracting the elevation of the bottom of the hole shown on the itemized list from the elevation of the natural ground at the pile site or from the elevation of the excavated section, whichever is lower. For foundations and end bents, the footage will be determined by subtracting the elevation of the bottom of the hole as shown on the itemized list from the elevation of the bottom of the footing or the bottom of the end bent caps, as applicable.

803.04.10 PDA Test Piles and Special Instrumentation Load Test. PDA test piles and

special instrumentation load test will be measured per each, which shall include a static load test with special instrumentation. Piles paid for as PDA test piles, special instrumentation load test, will not be included in the measurement of pay lengths for permanent piles. Completion of this pay item shall include the 1-day restrike after the initial pile driving, the special instrumentation load test, and the restrike within 24 hours after the static load test and the individual components will not be considered separately. Any additional restrike required by the Engineer on this type test pile will be paid for as a PDA Restrike.

803.04.11 PDA Test Piles and Conventional Load Test. PDA test piles and

conventional load test, will be measured per each, which shall include a static load test. Piles paid for as PDA test piles and conventional load test will not be included in the measurement of pay length s for permanent piles. Completion of this pay item shall include the 1-day restrike after the initial pile driving, the conventional static load test, and the restri ke within 24 hours after the static load test and the individual components will not be cons idered separately. Any additional restrike required by the Engineer on this type test pile will be paid for as a PDA Restrike.

803.04.12 PDA Test Pile. PDA test pile will be measured per each. Piles paid for as

PDA test piles will not be included in the measurement of pay lengths for permanent piles. Completion of this pay item shall include the 1-day and 7-day restrike after initial driving and individual components will not be consid ered separately. Any additional restrike required by the Engineer on this type test pile will be paid for as a PDA restrike.

803.04.13 Pile Restrike. Pile restrike will be measured per each pile restrike actually

performed on permanent piles or test piles as directed by the Engineer. The pile restrike will be conducted as directed by the Engin eer for bearing determination and may be conducted either with or without PDA monitoring.

803.04.14 Drilled Shaft. Drilled shaft will be measured per linear foot. Measurement

shall be the authorized length in feet of the completed concrete drilled shaft, including bells, of the diameter and containing the re inforcement shown on the plans. The length shall be determined as the difference between the plan top of shaft elevation and the final bottom of shaft elevation.

803.04.15 Test Shaft. Test shaft of the specified diamet er will be measured per each.

803.04.16 Trial Shaft. Trial shaft of the specified diameter will be measured per linear

foot.

803.04.17 Exploration. Exploration will be measured per linear foot of soil samples

and/or rock cores of the diameter and length required and authorized by the Engineer.

803.04.18 Casing. Casing shall be measured per linear foot. Such measurement shall be

full compensation for furnishing, placing, and removing when required, the casing in the shaft excavation.

803.05 Basis of Payment.

803.05.1 Test Piles . Test piles, measured as prescribed above, will be paid for at the

contract unit price per each.

803.05.2 Conventional Static Pile Load Tests. Conventional static pile load tests,

measured as prescribed above, will be paid for at the contract unit price per each. 803.05.3--Pile Shoes. If not covered by a contract item or otherwise required by the plans, metal shoes ordered by the Engineer will be paid for at double the invoice cost of the shoe. The cost of placing the pile shoes and driving piling with these additional requirements will not be paid for directly, and the cost th ereof shall be considered incidental to the respective pile driving pay item. 803.05.4--Piling. Piling of the type specified will be paid for at the contract unit price per linear foot. All costs for providing and placing pile driving tips and epoxy coal tar coating on steel pipe piling will not be paid for directly, and the cost thereof shall be considered incidental to the respective pile driving pay item.

803.05.5 Cut-Offs. When permanent prestressed concrete piles are required to be cut off

and the cut-offs are not necessitated by damage to the pile or as a result of a pile furnished in a length greater than that established by the pile list on the plans or furnished by the Bridge Engineer, the Contractor will be paid $60.00 per each pile cut-off for sizes smaller than 20 inches and $80.00 per each pile cut-off for sizes 20 inches and larger.

803.05.6 Extensions or Build-Ups. Extensions or Build-ups will not be paid for directly,

but will be included in payment for piling. No payment will be made for extensions or build-ups for test piles.

803.05.7 Blank.

803.05.8 Splices . Splices, measured as prescribed abov e, will be paid for at the contract

unit price per linear foot for the particular type pile splices.

803.05.9 Pre-formed Pile Holes. Pre-formed pile holes of the sizes specified will be paid

for at the contract un it price per linear foot.

803.05.10 PDA Test Piles and Special Instrumentation Load Test. PDA test piles and

special instrumentation load test, measured as prescribed above, will be paid for at the contract unit price per each.

803.05.11 PDA Test Piles and Conventional Load Test. PDA test piles and

conventional load test, measured as prescribed above, will be paid for at the contract unit price per each.

803.05.12 PDA Test Piles. PDA test piles, measured as prescribed above, will be paid

for at the contract unit price per each. All costs for providing and placing pile driving tips on steel pipe piling will not be paid for directly, and the cost thereof shall be consider ed incidental to the respective pile driving pay item.

803.05.13 Pile Restrike. Pile restrikes, measured as prescr ibed above, will be paid for at

the contract unit price per each.

803.05.14 Drilled Shafts. Drilled shafts of the type speci fied, measured as prescribed

above, will be paid for at the contract unit price per linear foot, which price shall include the cost of concrete, reinforcing steel, and all labor, materials including mineral slurry, equipment, and incidentals necessary to complete the drilled shaft.

803.05.15 Test Shafts. Test shafts of the type specified , measured as prescribed above,

will be paid for at the contract unit price per each, which price shall be full compensation for excavating the test shaft through whatever materials are encountered to the bottom of the shaft elevation shown on the plans or as authorized by the Engineer, concrete, reinforcement, required casings , special instrumentation load cell if required, conducting and reporting load test results, restoring the site as required, and all other expenses to complete the work.

803.05.16 Trial Shaft . Trial shafts of the type specifi ed, measured as prescribed above,

will be paid for at the contract unit price per linear foot, which price shall be full compensation for excavating the trial shaft thro ugh whatever materials are encountered to the bottom of the shaft elevation shown on th e plans or as authorized by the Engineer, concrete, reinforcement, required casings, sp ecial instrumentation if required, conducting and reporting load test results, restoring the site as required, and all other expenses to complete the work.

803.05.17 Exploration . Exploration, measured as prescribed above, will be paid for at

the contract unit price per linear foot, which price shall be full compensation for drilling, extracting, packaging and classifying the sa mples or cores, delivering them to the Department, furnishing concrete to fill the core hole, an d all other expenses necessary to complete the work.

803.05.18 Casings. Casings, measured as prescribed above, will be paid for at the

contract price per linear foot, which price shall be full compensation for furnishing, placing, and removing (when required) the casing in the shaft excavation. The prices thus paid shall be full compensation for all materials, tools, equipment, labor, and incidentals required to complete work. Payment will be made under: 803-A: Test Pile * - per each 803-B: Conventional Static Pile Load Test - per each 803-C: ___” Prestressed Concrete Piling - per linear foot 803-D: ___ Steel Piling -per linear foot 803-E: Concrete Piling Cut-off, Size - per each 803-F: ___” Pre-formed Pile Hole - per linear foot 803-G: PDA Test Pile and Special In strumentation Load Test - per each 803-H: PDA Test Pile and Conventional Load Test - per each 803-I: PDA Test Pile - per each 803-J: Pile Restrike - per each 803-K: Drilled Shaft, ___” Diameter - per linear foot 803-L: Test Shaft, ___” Diameter - per each 803-M: Trial Shaft, ___” Diameter - per linear foot 803-N: Exploration - per linear foot 803-O: ** Casing, ___” Diameter - per linear foot 803-P: ___” Steel Pipe piling, Wall Thickness ___” - per linear foot * Indicate Size and Type ** Temporary or Permanent SECTION 804 - CONCRETE BRIDGES AND STRUCTURES

804.01 Description. This work consists of constructing concrete bridges and structures

in accordance with these specifications and in reasonably close conformity with the dimensions, designs, lines, and grades indicated on the plans or established.