00921.14 899 Section 00921 - Major Sign Support Drilled Shafts
Description
00921.00Scope - This Work consists of excavating and constructing drilled, cast -in-place, reinforced
concrete shafts and footings for sign supports according to the Specifications and the Plans .
00921.01Definitions :
Drilled Shafts - Reinforced concrete sections, cast -in-place against in situ Soil, Rock , or a casing.
Temporary Casing - Casing installed to facilitate drilled shaft construction only and removed during or after concrete placement.
00921.02Subsurface Investigation - The soils and g eological exploration logs are available for
review through the Engineer's office. The data shown for each test boring or test pit applies only to that particular boring or test pit. Subsurface conditions may vary between borings or test pits. Core samples and laboratory test results, if obtained and performed for the Project, are available for review by contacting the Engineer.
The Foundation Data shown in the Plans is a compilation of pertinent information including, but not limited to, the s oils and g eological exploration logs.
Materials
00921.10Materials - Furnish Materials meeting the following requirements:
modified in this Section. Water may be added to the concrete mix at the Project Site only if allowed by the approved m ix design. Use Commercial Grade Concrete and anchor bolts according to
00920.10for drilled shaft cap
00921.13Steel Casing - Furnish temporary casing meeting the requirements of ASTM A252 or
ASTM A36. Use casing of sufficient strength to resist handling, transportation and installation stresses and the external stresses of the subsurface materials. Ensure that the casing is clean and watertight prior to placement in the drilled shaft excavation.
00921.14Drilling Slurry - Furnish drilling slurry m eeting one of the following requirements:
Property Test Requirement Density Mud Density API * 13B -1, Section 1 64 - 75 lb./cu. ft. Viscosity Marsh Funnel and Cup API * 13B -1, Section 2.2 26 - 50 sec./qt. pH Glass Electrode, pH Meter, or pH Paper 8 - 11 Sand Content Sand API * 13B -1, Section 5 4.0 % max. * American Petroleum Institute Maintain slurry temperature at 40 °F or more during testing. 00921.15 900
to the manufacturer's recommendations and the Contractor's quality control plan. The Sand content of synthetic slurry shall be less than 2.0 percent (API 13B-1, Section 5) prior to final cleaning and immediately prior to concrete placement.
drilled shaft. Use of water slurry without full -length casing will only be allowed with the Engineer's approval. Use water slurry meeting the following requirements:
Property Test Requirement (Maximum) Density Mud Density API * 13B -1, Section 1 70 lb./cu. ft. Sand Content Sand API * 13B -1, Section 5 2.0 % * American Petroleum Institute Do not use blended slurries.
00921.15Crosshole Sonic Log Access Tubes - Furnish steel crosshole sonic log (CSL) access
tubes meeting the following requirements:
• Steel access tubes shall be at least 1 1/2 inch inside diameter Schedule 40 pipe conforming to ASTM A53, Grade A or B, Type E, F, or S. • Use access tubes having a round, regular inside diameter free of defects and obstructions, including all pipe joints, in order to permit the free, unobstructed passage of the source and receiver probes used for the testing. Ensure that access tubes are watertight, free from corrosion with clean internal and external faces to ensure good bonding between the drilled shaft concrete and the access tubes. Fit the access tubes with watertight caps on the top and bottom. • Access tube acceptance will be based on manufacturer's certification that the furnished material meets the requirements of this specification.
00921.18Crosshole Sonic Log Cement Grout - Furnish non-epoxy grout or tendon grout from the
QPL or furnish a pumpable CSL cement grout consisting of neat cement and water that has a water -cement ratio between 0.38 and 0.45. Th e portland cement for the pumpable CSL cement grout shall meet the requirements of Section 02010.
00921.19Quality Control - Maintain and be responsible for quality control of the drilled shaft Work
throughout the construction operation. The Engineer w ill inspect all drilling operations and verify the suitability of all drilled shaft construction procedures. Provide lights, mirrors, weighted tape, weighted probe, personnel, and all assistance required for the Engineer to perform inspection during drilled shaft construction.
Labor
00921.30Personnel Qualifications - Perform the drilled shaft construction Work using a company
and personnel experienced in drilled shaft construction work. Submit a list to the Engineer for approval identifying the on- site supervisors and drill rig operators assigned to the Project and the companies experience relevant to the Proj ect. Experience shall be relevant to the anticipated subsurface materials, groundwater conditions, shaft size, depth and any special construction techniques required. Also provide the experience qualifications of the company performing the CSL testing. Before the 00921.40 901 preconstruction conference, provide the following information to verify the firm's experience and the qualifications of personnel scheduled to perform the drilled shaft construction and CSL testing:
• Submit a project reference list of at least t hree separate foundation projects, successfully completed in the last 5 years, with Drilled Shafts of diameters and depths equal to or larger than those shown in the Plans and in ground conditions similar to those indicated. Include a brief description of each project and the owner's contact person's name and current phone number for each project listed. • On-site supervisors shall have at least 2 years ' experience in supervising construction of drilled shaft foundations of similar diameter and depth and sco pe to those shown in the Plans and in similar geotechnical conditions to those described in the geotechnical report. Experience shall include the direct supervisory responsibility for the on-site construction operations. • Drill operators shall have at leas t 1 year experience in the construction of drilled shaft foundations. • Perform CSL testing using an independent testing organization retained by the Contractor and approved by the Agency. Furnish personnel experienced in operating the CSL testing equipment . Submit the CSL testing firm qualifications according to 00921.40(a). The CSL testing firm shall have successfully performed CSL testing on a minimum of five projects during the last 3 years. CSL testing personnel shall be trained in the operation of the CSL equipment and have at least 1 year of experience in operating CSL testing equipment on a minimum of 10 shafts. The Engineer will respond within 21 Calendar Days after receipt of the submittal. Do not begin Work on any D rilled Shafts until the qualifications have been approved. The Engineer may suspend the drilled shaft construction if the Contractor substitutes unapproved personnel during construction. Submit requests for substitution of either on- site supervisors, drill operators, or CSL testing personnel to the Engineer, who will have 7 Calendar Days to respond to each request. Additional costs resulting from the suspension of Work due to the changing of personnel is the Contractor's responsibility, and no adjustment in Contract Time resulting from the suspension of Work will be allowed.
Construction
00921.40Submittals - Provide the following submittals to the Agency for review and approval:
construction, submit the following:
• The sequence of drilled shaft construction as it relates to the overall construction plan. • A review of Equipment suitability based on the Contractor's understanding of the site subsurface conditions. Include a project history of the drilling Equipment that demonstrates the successful use of the Equipment for Drilled Shafts of equal or greater size in similar subsurface conditions. • Details of shaft excavation methods, including proposed drilling methods and a disposal plan for excavated material. Include details of methods used to perform final cleaning of the excavation. Inc lude a disposal plan for any water or contaminated concrete expelled from the top of the shaft if applicable. • Details of the proposed methods for ensuring drilled shaft stability during excavation and concrete placement. • Details for the use of drilling slurry including mix design, slurry head requirements, mixing methods, maintaining, and disposing of the slurry if applicable. Include a discussion of the suitability of the proposed drilling slurry in relation to the anticipated subsurface conditions. 00921.40 902 • A pla n for quality control of all drilling slurries, if their use is proposed. In the quality control plan, include property requirements, required tests and test methods to ensure the slurry performs as intended. Submit to the Engineer the name and current p hone number of synthetic slurry manufacturer's representatives who will provide technical assistance during construction. Provide the names of the Contractor's personnel assigned to the Project and trained by the synthetic slurry manufacturer in the proper use of synthetics slurries. • Unstamped reinforcing steel shop drawings and details of reinforcement placement, including bracing, splicing, centering, lifting methods, and the method for supporting the reinforcement according to 00150.35. Include details on the type, number, and placement of spacers and other devices for ensuring the reinforcing cage position is maintained during construction. Include details for attaching the CSL test access tubes to the reinforcing cage if applicable. • Evidence that the proposed materials and concrete mix design conform to all applicable Specifications. • Documentation that assures that the concrete mix design will maintain the required slump retention properties specified in Section 02001. • If the concrete mix design allows the addition of water at the Project Site, documentation that specifies the amount of water that may be added and allowable methods for adding the water. • Details of concrete placement, including proposed operational procedures for pumping and tremie methods. Include details for grout placement in the crosshole sonic logging test access tubes after testing is completed if applicable. • Detailed procedures for temporary casing installation and removal. Include casing diameters, dimensions, and depths and th e methods and Equipment for casing installation and removal. • CSL testing company performing the CSL testing Work , including documentation demonstrating that the company, and company personnel, meets the required qualifications. • Confinement methods required to contain drilling fluids, spoils, waste concrete and other products from contacting sensitive environmental areas according to Section 00290 and all applicable regulatory permits. • Methods for protecting existing Structures according to 00170.82.
The Engineer will approve or reject the drilled shaft installation plan within 21 Calendar Days after receipt of all submissions. Provide any additional information and submit a revised plan, if requested, for review and approval. All proce dural approvals given by the Engineer will be subject to trial in the field and will not relieve the Contractor of the responsibility to satisfactorily complete the Work . Submit requests for modification of adopted procedures to the Engineer. Allow 21 Calendar Days for approval of modifications. Do not begin drilled shaft construction Work until all drilled shaft submittals have been approved.
plan to the Engi neer for approval. Furnish all Materials and Work , including engineering analysis and design, needed to correct unacceptable Drilled Shafts, at no additional cost to the Agency. Do not begin repair operations before remedial procedures or designs are approved. Any modifications to the dimensions or Material of the Drilled Shafts shown that are proposed in the repair plan will require stamped calculations and Working Drawings according to 00150.35.
Inspection Report for each drilled shaft, detailing the actual location, alignment, elevations, dimensions, and quantities of the shafts.
Submit the report within 21 Calendar Days after the completion and acceptance of each shaft. A "Drilled Shaft Inspection Report" form is available from the Engineer.
00921.42 903 (d) Concrete Placement Logs and Volume Curves - Measure and record all concrete placed into Drilled Shafts using standard ODOT forms designated for t his purpose or other forms approved by the Engineer. Provide the Engineer with a completed Drilled Shaft Concrete Placement Log and Concrete Volume Curve Form for each drilled shaft within 24 hours after completion of shaft concrete placement.
00921.41Drill Shaft Coordination Meeting - Hold a drilled shaft coordination meeting at least
7 Calendar Days before beginning any shaft construction Work at the site to discuss construction procedures, schedules, staging, personnel, Equipment to be used, and other elements of the approved shaft installation plan as specified in 00921.40. If synthetic slurry is used to construct the shafts, the frequency of scheduled site visits to the Project Site by the synthetic slurry manufacturer's representative will be dis cussed. Those attending the meeting include:
• Representing the Contractor - The superintendent, on- site supervisors, and all supervisors in charge of excavating the shaft, placing the casing, mixing and installing slurry as applicable, placing the steel r einforcing bars, and placing the concrete. If synthetic slurry is used to construct the shafts, the slurry manufacturer's representative and a Contractor's employee trained in the use of the synthetic slurry shall also attend.
• Representing the Contractin g Agency - The Project Engineer, key inspection personnel, and designers of record or their appointed representatives.
If the Contractor's key personnel change, or if the Contractor proposes a significant revision of the approved shaft installation plan, hold an additional meeting before any additional shaft construction operations are performed.
00921.42Construction Tolerances - Excavate Drilled Shafts as accurately as possible at the
locations shown and within the specified tolerances listed below. Determine the drilled shaft dimensions and alignment with approved methods. The following construction tolerances apply to Drilled Shafts unless otherwise stated:
• Horizontal Position (At the Plan Elevation of the Top of Shaft) - 3 inch horizontal tolerance from the location shown. • Top Elevation of Shaft Concrete - Plus 3 minus 0 inches from the plan top of shaft elevation.
• Vertical Alignment in Soil - May not vary from the plan alignment by more than 1.5 percent of the shaft length.
• Vertical Alignment in Rock - May not vary from the plan alignment by more than 2 percent of the shaft length.
• Top of Steel Reinforcement - Plus 3 minus 0 inches from the plan top of steel reinforcement elevation. Maintain 3 inch of cover. Frequently check the plumbness, alignment, and dimensions of the shaft during construction. Correct all out -of-tolerance shaft excavations and completed shafts to the satisfaction of the Engineer. Materials and Work necessary to complete corrections for out -of-tolerance Drilled Shafts will be at no additional cost to the Agency , and no extension of the Project completion date will be granted. Materials and Work necessary to complete corrections for out -of-tolerance Drilled Shafts resulting from the removal of unexpected drilled shaft obstructions will be paid for according to 00195.20.
00921.43 904 00921.43 Drilled Shaft Excavation - Perform drilled shaft excavation according to the following:
Provide and maintain stabilized drilled shaft sidewalls and bottoms for the full depth of the excavation, using approved M aterials, Equipment and methods. If caving or other unstable conditions occur during any construction procedure, stop further construction, notify the Engineer, and stabilize the shaft excavation by approved methods and submit a revised installation plan which addresses the problem and prevents further instability. Do not continue withs haft construction until any damage which occurred has been repaired according to the Specifications and until receiving the Engineer's approval of the revised shaft installation plan.
If the Engineer has reason to believe that the drilled shaft excavation techniques or workmanship have been deficient, so that the integrity of any excavation is in question, Work on that drilled shaft may be stopped. Do not resume drilled shaft excavation until the deficient excavation techniques or workmanship have been ch anged to the Engineer's satisfaction.
Dispose of materials removed from the shaft excavations according to 00290.20.
Do not leave partially completed shaft excavations open overnight unless they are cased full depth or otherwise stabilized with approved methods. If approved by the Engineer, a partially excavated shaft may be left open overnight, provided that the excavation:
• Is stabilized at the bottom, sides and surface to prevent Soil caving or swelling or a reduction of Soil strength, and • Is covered at the surface to protect the public.
Extend the drilled shaft excavation if the Engineer determines that the subsurface materials encountered are not capable of providing the required bearing resistance or differ from those anticipated in the des ign of the D rilled Shafts.
to existing Structures and utilities. Preventive measures 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 such as the dri ving and vibrating of casing or sheeting, drilling of the shaft, or from blasting, if blasting is allowed. Repair all damage caused to existing Structures, utilities or other facilities, resulting from drilled shaft construction activities, at no additional cost to the Agency.
of sufficient quantities to meet the needs of the anticipated construction method.
encountered that was not revealed by the Agency's site investigation, and that would cause a significant decrease in the rate of advancement if removed using the techniques and Equipment used successfully to excavate the shaf t. The Engineer will be the sole judge of the significance of any reduced rate of shaft advancement and the classification of any unexpected obstructions. Removal of unexpected obstructions from the shaft excavation will be paid according to 00195.20.
considered unexpected obstructions and shall be removed without additional compensation. Drilling tools lost during the course of removing unexpected drilleds haft obstructions will be paid according to 00195.20.
representative to provide technical assistance at the site prior to use of the slurry, who shall r emain 00921.43 905 at the site during construction and completion of a minimum of one drilled shaft to adjust the slurry mix for the specific site subsurface conditions. After the manufacturer's representative is no longer at the site, provide the approved personnel t rained in the use of the synthetic slurry for the remainder of the shaft slurry operations to supervise the proper slurry mix design and quality control procedures.
All in -hole drilling slurry shall meet the required slurry Specifications during excavatio n and prior to concrete placement. Clean, recirculate, de-sand or replace the slurry to maintain the required slurry properties. Unless otherwise approved, maintain the level of slurry in the excavation at not less than 5 feet above the groundwater level for mineral slurries or 10 feet above the groundwater level for synthetic or water slurries. Maintain the slurry level a sufficient distance above all unstable zones to prevent bottom heave, caving or sloughing.
Maintain the required slurry properties and levels at all times during shaft construction, including work stoppages, unless other approved stabilization methods are applied.
Feed slurry continuously into the shaft excavation as drilling progresses so that a stable excavation is maintained. Use a self -priming pump to reclaim the slurry. Keep a standby pump available during the drilling operation.
appropriate storage facility. Collect sample set s from the storage facility and perform tests to ensure the slurry conforms to the specified material properties before introduction into the drilled shaft excavation. A sample set shall be composed of samples taken at mid-depth and within 24 inches of th e bottom of the storage facility.
Sample and test all slurry in the presence of the Engineer, unless otherwise directed. The sample sets of slurry within the excavation shall consist of samples taken at mid-depth of the excavation and within 24 inches of the bottom of the excavation. Collect and test sample sets during the drilling operation as necessary to ensure the specified properties of the slurry are maintained. Clean, recirculate, de-sand, or replace the slurry as necessary to maintain the specif ied slurry properties. Final cleaning of the excavation and placement of concrete is not allowed until the test results indicate the slurry properties are as specified.
Perform a minimum of two sets of slurry tests per 8 -hour work shift, the first test b eing done at the beginning of the shift. Field conditions may require more frequent testing to ensure acceptable slurry properties.
Make copies of all slurry test results available to the Engineer on request.
bottom of the drilled shaft excavations. No more than 1 inch of loose or disturbed material will be allowed at the bottom of the excavation. Notify the Engineer of completion of each drilled shaft excavation to permit inspection before proceeding with construction. Measure final shaft depths with a suitable weighted tape or other approved method after final cleaning to determine that the shaft bottom meets the requirements in the Contract. Do not proceed with shaft construction until the bottom cleanliness requirements have been met and the bottom (shaft tip) elevation is approved.
00921.45 906 00921.45 Reinforcing Steel - Furnish and place reinforcing steel as shown and according to the following:
approved the final elevation of the bottom of the shaft.
In each shaft, place reinforcing steel to the top elevation shown. Support the reinforcing cage to prevent distortion or settlement during concrete placement. Support the reinforcing cage such that the supporting mechanism does not obstruct the center of the shaft and allows concrete placement vertically down the center of the shaft. If concrete placemen t does not immediately follow cage placement, remove the reinforcing cage from the excavation and rectify the integrity of the excavation prior to reinstallation of the cage.
manner that does not cause permanent racking or distortion. Show bracing and any extra reinforcing steel required for fabrication of the cage on the submitted shop drawings. Remove cross bracing during cage placement unless otherwise approved.
otherwise shown or approved.
bars or other approved devices around the reinforcing cage. Place spacing devices on minimum 10 foot vertical spacings the full length of the shaft. At each 10 foot level, place spacers on a minimum 30 inch circumferential spacing with at least three spaces per level. Do not use wood spacers or concrete dobies. Provide details of the proposed centering method on the shop drawings submitted according to 00921.40.
00921.46Crosshole Sonic Log Test Access Tubes - Furnish and install access tubes for CSL
testing as shown. At tach CSL access tubes securely to the interior of the reinforcement cage as near to parallel as possible in each drilled shaft and in the pattern shown. Extend the access tubes from the bottom of the reinforcement cage to at least 24 inches above the top of the shaft. Joints required to achieve full -length access tubes shall be watertight. Do not damage the access tubes during reinforcement cage installation and concrete placement. Fill the tubes with potable water, according to 02020.10(b), as soon as possible, but no more than 1 hour after concrete placement and reinstall the top watertight caps. Check water level and top off as needed.
Replace all access tubes that the test probe cannot pass through to the full depth of the shaft at no additional cost to the Agency. Replace all damaged access tubes with 1.5 to 2.0 inch diameter holes cored through the concrete for the entire length of the shaft. Unless otherwise directed, locate replacement core holes approximately 6 inches inside the reinforcement. Do not damage the shaft reinforcement during coring operations.
Fill the access tubes with grout only after all CSL testing has been completed and the shaft has been accepted.
00921.47Concrete - Furnish and place concrete according to the following:
and with the approval of the Engineer. Prior to concrete placement, ensure the shaft clean-out requirements are met according to 00921.43(h) and the properties of the slurry, if used, conform to the Specifications . Shaft concrete may be placed without mechanical vibration in those areas of the drilled shaft that are not formed or are below the ground line or the water surface.
00921.47 907 Place concrete continuously until concrete at the top of the shaft is free of water, Soil, and debris, and uncontaminated concrete extends to the plan top- of-shaft elevation. Dispose of all contaminated concrete expelled from the top of the shaft in an approved manner. Remove waste concrete from the site. If a delay in concrete placement occurs because of a delay in concrete delivery or other factors, reduce the placement rate to maintain a flow of fresh concrete into the shaft excavation.
Allow a maximum of 60 minutes between concrete placements and use no concrete older than 90 minutes from batch time. Use procedures for concrete placement which ensure that the concrete within the shaft becomes a monolithic, homogeneous unit. Place concrete using hoses or pipes having watertight joints. For concrete placement by gravity tremie, use hose or pipe having an inside diameter of at least 8 inches. For placement by concrete pump, use hose with inside diameter of at least 4 inches. Provide an alternate delivery system that can be used in case of failure of the primary delivery system. Place concrete only against the bottom of the drilled shaft or into fresh concrete.
If caving occurs during concrete placement, the shaft may be rejected.
conditions are met:
• No more than 3 inches of water is present in the bottom of the excavation at the beginning of the pour. • Groundwater seepage into the excavation is at a rate of no more than 12 inches per hour. • Shaft diameter is greater than or equal to 3 feet.
Under free-fall placement, deposit concrete through the center of the reinforcement cage by a method which prevents segregation of Aggregates and splashing of concrete on the reinforcement cage. Place concrete so that the free-fall is vertical down the center of the shaft without hitting the sides, the steel reinforcing bars or steel cage bracing.
requirements for dry concrete placement, stabilize water inflow and place the concrete under water or slurry with a tremie pipe or pump hose according to 00540.48(e). Place concrete continuously from the bottom of the shaft to the top- of-shaft el evation shown. Use a plug in the tremie pipe or pump hose to force water or slurry ahead of the advancing flow of fresh concrete. Dispose of all displaced water, slurry, or waste concrete according to 00290.20. When groundwater, the drilling water or sl urry in the shaft excavation is to be removed by pumping during concrete placement, have a standby pump available. Place concrete in a continuous operation so that the concrete always flows upward within the shaft. Withdraw the delivery hose or pipe slowly as the elevation of the fresh concrete rises in the shaft. Keep the discharge end of the pipe or hose at least 5 feet below the surface of the concrete after the concrete has reached a depth of 5 feet. Maintain sufficient concrete inside the hose or pipe to prevent drilling fluid from entering. During concrete placement, provide and maintain markings on the tremie pipe or pump hose, or a sounding device or other appropriate method to determine the relative elevations of the fresh concrete surface and the bottom end of the pipe or hose. Raise the bottom end of the pipe or hose only when the pipe or hose has a sufficient head of fresh concrete to prevent the formation of a void at the bottom.
of 7 Calendar Days by covering with wet burlap overlain with plastic sheets or by keeping top of concrete under water. Keep the burlap wet during the concrete cure. 00921.48 908 Prior to placing any fresh concrete on top of a completed shaft, clean the upper surface of the concrete by removing all scum, laitance, loose Gravel, and sediment and chip off any high spots on the upper surface that would prevent the steel reinforcing bar cage from being properly placed in the position shown. Remove all loose material and poor quality concrete at the top of the shaft down to sound concrete prior to performing any required CSL testing.
placement. Do not start temporary casing removal until the level of fresh concrete within the casing has reached a depth of at least 10 feet or the level necessary to adequately counteract the external hydrostatic pressure head. As the temporary casing is withdrawn, maintain a minimum 5 feet head of concrete above the bottom of the casing. A slight downward movement of the casing while exerting downward pressure, or hammering or vibrating the casing will be allowed to facilitate extraction. Extract the casing so that concrete is cast directly against the surrounding in-situ material. Check the elevation of the top of the reinforcing cage before and after temporary casing extraction for conformance with the construction tolerance criteria of 00921.42. Casing that cannot be extracted during, or immediately after, the concrete placement operation may be cause for rejection of the shaft.
00921.48Drilled Shaft Testing and Acceptance - Acceptance of D rilled Shafts will be based on the
Engineer's review of the results of CSL, or other, integrity testing if conducted, field inspection reports and visual observations during drilled shaft construction. The Engineer has final authority on the approval of D rilled Shafts. For shafts that are integrity tested, the Engineer will determine final acceptance of each tested shaft, based on the i ntegrity test results and inspection reports and will provide a response to the Contractor within 5 Calendar Days after receiving the CSL test report.
crossholes onic log testing and analysis on the first drilled shaft completed at each foundation and subsequent shafts as specified or designated for testing by the Engineer. Provide CSL testing Equipment conforming to the requirements of ASTM D6760 and approved by the Engineer. Provide all necessary access and other support to the CSL testing firm necessary to do the CSL testing Work .
Perform one CSL test on each shaft designated for testing. A single CSL test consists of all ultrasonic profile combinations in a given shaft. Test completed drilled shaft foundations using Ultrasonic Crosshole Testing methods ((CSL) Testing) according to ASTM D6760. Inform the Engineer of scheduled CSL testing at least 3 Calendar Days prior to the testing. Perform all CSL testing using the Contractor's CSL technician in the presence of the Engineer.
Allow at least 3 Calendar Days of curing time before testing unless otherwise approved. Additional curing time beyond 3 Calendar Days may be required if the shaft concrete contains admixtures such as set retarding admixture or water reducing admixture. Additional CSL testing required due to the CSL testing being conducted on concrete that has not cured sufficiently is at no additional cost to the Agency. Additional curing time required due to concrete admixtures will not be grounds for additional compensation or time extensions.
data, with interpretation of the test results, to the Engineer at the completion of each test. Provide copies, either hardcopies or electronic files, of the raw test data as requested. Mark the test data files to identify, as a minimum, the Structure , bent and shaft number, the date of CSL testing, depths of testing and any other pertinent information.
00921.49 909 Submit three copies of a final CSL Test Report for each shaft tested according to ASTM D6760. Provide electronic file copies of the raw CSL data measurements compatible with the Cross Hole Ultrasonic Monitor ( CHUM) program, if requested. The report shall summarize the CSL testing performed, data analysis, and interpretation of CSL data with special attention made to the identification and location of any anomalies or possible defects. Provide interpretation o f the CSL test data in terms of overall shaft integrity and acceptance. Submit all reports to the Engineer within 5 Calendar Days of the performance of the tests.
to identify the location, extent and condition of possible shaft defects if requested by the Engineer. Additional testing and investigation may include, but is not limited to, additional CSL testing, excavation Work or core drilling.
If requested by the Engineer, drill a core hole in any questionable quality shaft to explore the shaft condition. The number, location and depths of the core holes will be determined by the Engineer. Submit the method and Equipment used to drill and remove cores from the shaft to the Engineer for review and approval prior to drilling. Use a coring method that provides complete core recovery and minimizes abrasion and erosion of the core. If a defect is confirmed, as determined by the Engineer, all investigation costs associated with identifying the defect will be at no additional cost to the Agency and no extension of the Project completion date will be granted, regardless of whether the identified defect is repaired or not.
If no defect is identified in the investi gation Work , and the CSL tubes were satisfactorily installed according to ASTM D6760 and accepted, the Agency will pay for all coring and excavation costs associated with the additional investigation and grant an appropriate time extension, if required, according to Section 00190 and Section 00195. If it is determined by the Engineer that the CSL tubes were not installed properly thus invalidating the CSL test results, all coring, excavation, and other investigation and evaluation costs will be at no addit ional cost to the Agency and no extension of the Project completion date will be granted.
Fill all core holes with grout only after the evaluation process is completed and the shaft is accepted and approved.
Perform additional CSL testing, or other investigation required, as directed by the Engineer, to confirm the quality of the completed shaft repair Work at no additional cost to the Agency with no time extension granted.
For temporary casing not extracted from the shaft excavation, submit a repair plan or a structural evaluation to the Engineer for approval according to 00921.40. If caving occurs during concrete placement submit a repair plan to the Engineer for approval.
00921.49Scheduling and Restrictions - Unless otherwise approved, do not proceed with
construction of subsequent shafts until the CSL testing has been completed on the first drilled shaft and the results have been appr oved and accepted, in writing by the Engineer. Approval to proceed with the construction of subsequent shafts, before receiving approval of the first shaft will be based on the Engineer's observations of the Contractor's workmanship during construction of the first shaft and the Engineer's review and assessment of the following:
• The Contractor's conformance with the approved shaft installation plan. The Contractor's daily reports and Inspector 's daily logs of excavation, rebar, and concrete placement. The concrete placement logs and volume curves.
00921.80 910 Written notification will be provided to the Contractor on whether or not to proceed with subsequent shaft construction within 24 hours after completion of the first shaft. If the Engineer determines the first shaft to be of questionable quality, discontinue all shaft construction until the CSL test results of the first shaft are received and reviewed and the shaft accepted, in writing, by the Engineer. Denial of permission to proceed with subsequent shaft cons truction will not be cause for C ontract Time extension.
Do not proceed with the third drilled shaft until the final CSL test results from the first drilled shaft has been received and reviewed and the shaft accepted, in writing, by the Engineer.
After th e first drilled shaft on the Project has been accepted, make no significant changes in construction methods, Equipment , or M aterials used to construct subsequent shafts, unless otherwise approved.
Measurement
00921.80Measurement - The quantities of Work performed under this Section will be measured on
the length basis . Measurement will be the length from the bottom of the shaft to the top of the sign support footing. If directed to construct Drilled Shafts below the elevations bottom of shaft shown, the drilled shaft will be measured from the revised bottom of shaft. The estimated quantities of M aterials for the sign support drilled shaft foundations will be listed in the Special Provisions.
Payment
00921.90Payment - The accepted quantities of Work performed under this Section will be paid for
at the Contract unit price, per foot for the item "____ Inch Diameter Sign Support Drilled Shaft Foundation".
The diameter of the drilled shaft will be ins erted in the blank.
Payment will be payment in full for furnishing and placing all Materials, and for furnishing all Equipment , labor, and Incidentals necessary to complete the Work as specified. Work completed according to Section 009 20 shall be Inciden tal to thisS ection. No separate or additional payment will be made for:
• furnishing drilling Equipment • temporary casings • drilled shaft excavation • drilled shaft concrete • drilled shaft reinforcement • CSL Equipment mobilization • CSL test access tubes • CSL tes ts shaft clean out below the bottom of shaft shown