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605201 DYNAMIC PILE TESTING BY CONTRACTOR FOR TEST PILE INITIAL DRIVE EACH

DE · 2025 Standard SpecificationsBook pages 212–232View official source ↗

DRIVEN PILES SECTION 605 202 ITEM DESCRIPTION UNIT 605146 INSTALL PRECAST PRESTRESSED CONCRETE PILES, 30" X 30" LF 605150 INSTALL TIMBER TEST PILES - TREATED, 12" LF 605151 INSTALL TIMBER TEST PILES - TREATED, 14" LF 605152 INSTALL TIMBER TEST PILES - TREATED, 16" LF 605160 INSTALL CAST -IN-PLACE CONCRETE TEST PILES, 12" LF 605161 INSTALL CAST -IN-PLACE CONCRETE TEST PILES, 14" LF 605162 INSTALL CAST -IN-PLACE CONCRETE TEST PILES, 16" LF 605163 INSTALL CAST -IN-PLACE CONCRETE TEST PILES, 18" LF 605170 INSTALL STEEL H TEST PILES, HP 10 ” X 42 ” LF 605171 INSTALL STEEL H TEST PILES, HP 12 ” X 53 ” LF 605172 INSTALL STEEL H TEST PILES, HP 12 ” X 63 ” LF 605173 INSTALL STEEL H TEST PILES, HP 12 ” X 74 ” LF 605174 INSTALL STEEL H TEST PILES, HP 14 ” X 73 ” LF 605175 INSTALL STEEL H TEST PILES, HP 14 ” X 89 ” LF 605176 INSTALL STEEL H TEST PILES, HP 14 ” X 102 ” LF 605180 INSTALL STEEL PIPE TEST PILES, 24" LF 605181 INSTALL STEEL PIPE TEST PILES, 30" LF 605182 INSTALL STEEL PIPE TEST PILES, 36" LF 605183 INSTALL STEEL PIPE TEST PILES, 48" LF 605184 INSTALL STEEL PIPE TEST PILES, 12" LF 605190 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 12" X 12" LF 605191 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 14" X 14" LF 605192 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 16" X 16" LF 605193 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 18" X 18" LF 605194 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 20" X 20" LF 605195 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 24" X 24" LF 605196 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 30" X 30" LF 605200 PILE RESTRIKE EACH 605201 DYNAMIC PILE TESTING BY CONTRACTOR FOR TEST PILE INITIAL DRIVE EACH 605202 DYNAMIC PILE TESTING BY CONTRACTOR FOR RE -STRIKE OR PRODUCTION PILE EACH 605210 STATIC LOAD TEST FOR DRIVEN PILES EACH

DRILLED SHAFTS SECTION 606 203 SECTION 606 — DRILLED SHAFTS

606.1Description.

This work consists of constructing drilled shafts.

606.2Materials.

A.Self-Consolidating PCC, Class A Section 1022 and 1036

B.Access Tubes for Crosshole Sonic Log Testing Section 1033

C.Steel Casings Section 1034

D.Slurry Section 1035

E.Reinforcing Steel Section 1037

F.Access Tube Grout Section 1047 .3

G.Grout for Abandoned Exploratory Drilling in accordance with DNREC’s Regulations Governing the

Construction and Use of Wells, Section 5.8.12.1

H.Liquid Membrane -Forming Compou nds for Curing Section 1045.7

606.3Construction.

606.3.1 Submittals, Approvals, and Meetings.

A.At the time of bid, submit the drilled shaft and exploratory drilling specialty contractor

qualifications verifying successful completion of at least 3 separate foundation projects within the last 5 -years. Ensure that the 3 projects submitted involved drilled shafts and exploratory drilling of similar diameter, depth, and subsurface geotechnical conditions as those shown in the contract. Include a brief description of each project and the owner's cont act person's name and current phone number for each pr oject listed.

B.Experience and Personnel.

1.Submit a list, identifying the on -site supervisors and drill rig operators assigned to the project. In

the list, include a detailed summary of each individual's experience in drilled shaft excavation operations and placement of assembled reinforcing cages and concrete in drilled shafts.

2.Provide on -site supervisors with a minimum of 2 -years of experience in supervising drilled shaft

foundations of similar diameter and depth and geotechnical conditions as those shown in the contract. Direct supervisory responsibility for the on -site drilled shaft construction operations is necessary to s atisfy the Department's work experience requirement. Unacceptable experience includes project management level positions that indirectly supervised on -site drilled shaft construction operations.

3.Drill rig operators must have a minimum of 1 -year of experience in construction of drilled shaft

foundations.

4.The engineer will approve or reject the contractor's qualifications and field personnel within 10

working days after receipt of submission. Do not start work on any drilled shaft until the engineer approves the contractor's qualifications and field pers onnel. The engineer may suspend the drilled shaft construction if the contractor substitutes field personnel without prior DRILLED SHAFTS SECTION 606 204 approval by the engineer. The contractor shall accept full responsibility for the additional time resulting from the suspension of work and the Department will make no adjustments in contract time resulting from such suspension of work.

C.Drilled Shaft Installation Plan.

1.In preparing the submission narrative, reference the available subsurface geotechnical data

provided in the contract documents and any geotechnical reports prepared for this project. Do not begin work until receipt of the engineer's written approval of all the required submittals. Provide at a minimum the following information:

a.A description of overall construction operation sequence and the sequence of drilled shaft

construction when in groups or lines.

b.A list, description, and capacities of all proposed equipment. Describe the reasons for

selecting the proposed equipment and describe equipment suitability for the anticipated site and subsurface conditions. Include a project history of the drilling equ ipment, demonstrating the successful use of the equipment on shafts of equal or greater size in similar subsurface geotechnical conditions.

i.Use excavation and drilling equipment capable of excavating to a depth 20 percent beyond

the maximum shaft length shown in the contract.

c.Drilled shaft excavation methods, including proposed drilling methods, methods for cleanout

of the bottom of the drilled hole, and a disposal plan for excavated material and drilling slurry. Include a review of method suitability to the anticipated site and subsurface geotechnical conditions, including boulder and obstruction removal techniques if such are indicated in the contract subsurface geotechnical information or contract.

d.The Department will not allow blasting unless specifically stated in the contract or authorized

in writing by the engineer.

e.Methods used to ensure drilled shaft hole stability during excavation and concrete placement.

Include a review of method suitability to the anticipated site and subsurface geotechnical conditions.

f.Procedures for mixing, using, maintaining, and disposing of slurry. Provide a detailed mix

design including all additives and the specific purpose of additives in the slurry mix and a discussion of its suitability to the anticipated subsurface geotechni cal conditions for the proposed slurry.

g.A quality control plan for the slurry. Include details for the planned tests and test methods and

the minimum and maximum property requirements the slurry must meet to show that the slurry will function as intended in the anticipated subsurface conditio ns and shaft construction methods. At a minimum, include the following tests in the slurry quality control plan as shown in Table 606.3 -1: Table 606.3 -1. Minimum Tests Required in the Slurry Control Plan Property Test Method Density Mud Weight (Density), API RP 13B -1, Section 1 Viscosity Marsh Funnel and Cup, API RP 13B -1, Section 2.2 DRILLED SHAFTS SECTION 606 205 pH Glass Electrode, pH Meter (ASTM E70), or pH Paper Sand Content Sand, API RP 13B-1, Section 5

h.Reinforcing steel working drawings with details of reinforcement placement including:

i.Type and location of splices;

ii. reinforcement cage support and centralization methods; iii. bracing and extra reinforcing steel required for fabrication of the reinforcement cage; iv. type and location of all spacers;

v.thermal integrity profiling thermal wire cables;

vi. access tubes for cross hole sonic log testing and other instrumentation; and vii. procedures for lifting and setting the reinforcement cage.

i.When proposed or required, provide the following casing information:

i.Casing dimensions and detailed procedures for permanent casing installation;

ii. temporary casing installation and removal; and iii. methods of advancing the casing, along with the means used for excavating the drilled shaft hole in accordance with Section 606.3.5.

j.When using temporary casing, details of the method to extract the temporary casing and

maintaining shaft reinforcement in proper alignment and location and maintaining the concrete slump to keep concrete workable during casing extraction.

k.Concrete placement details including:

i.Proposed equipment and procedures for delivering concrete to the drilled shaft;

ii. placement of the concrete into the shaft; iii. initial placement and raising of the tremie or pump line during placement; iv. size of tremie and pump lines;

v.operational procedures for pumping;

vi. sample uniform yield form for plotting concrete volume placed versus the depth of shaft for shaft concrete placement; vii. time limits for concrete placement with references cited used in determination; and viii. the method to form a horizontal construction joint during concrete placement.

l.When applicable, include a description of the material to temporarily backfill a drilled shaft

excavation hole during a stoppage of the excavation operation, as well as the method to place and remove the material.

m.Details of procedures to prevent loss of slurry or concrete into waterways, sewers, and other

areas in accordance with the contract. DRILLED SHAFTS SECTION 606 206 n. Method and materials to fill or eliminate all voids below the top of shaft between the plan shaft diameter and excavated shaft diameter, or between the shaft casing and surrounding soil, if permanent casing is specified.

o.Details of required load tests including equipment, instrumentation, procedures, calibration

data for test equipment, calculations, and drawings.

p.Details and procedures for protecting existing structures, utilities, roadways, and other

facilities during drilled shaft installation.

q.Include measures to prevent excessive caving of the drilled shaft excavation and monitoring

and controlling the vibrations from the drilled shaft installation.

2.The engineer will evaluate the drilled shaft installation plan for conformance with the contract.

Schedule a shaft installation plan submittal meeting, following review of the contractor's initial submittal of the plan. The following people must attend the shaft installation plan submittal meeting:

a.The superintendent, on -site supervisors, and other contractor personnel involved in preparing

and executing the drilled shaft installation plan.

b.The project engineer and Department's personnel involved with the structural, geotechnical,

and construction review of the drilled shaft installation plan, together with the Department's personnel who will provide inspection and oversight during the dri lled shaft construction phase of the project.

3.Submit any proposed updates or modifications to the drilled shaft installation plan to the

engineer. The engineer will evaluate the new information for conformance with the contract within 14 calendar days after receipt of the submission.

D.Slurry Technical Assistance.

1.When using slurry to construct drilled shafts, provide, or arrange for, technical assistance from

the slurry manufacturer as specified in Section 606.3.5.E. Submit the following to the engineer:

a.The name and phone number of the slurry manufacturer's technical representative assigned

to the project.

b.The names of the contractor’s personnel assigned to the project and trained by the slurry

manufacturer’s technical representative in the proper use of slurry. In the submittal, include a signed training certification letter from the slurry manufacturer for each individual, including the training dates.

E.Drilled Shaft Preconstruction Conference.

1.Hold a drilled shaft preconstruction conference at least 5 calendar days before the contractor

begins shaft construction work. Discuss boring information, construction procedures, personnel, equipment, and other elements of the accepted shaft installati on plan as specified in Section 606.3.1.C. Discuss the frequency of scheduled site visits by the slurry manufacturer’s representative. The following people must attend:

a.The superintendent.

b.On-site supervisors.

c.Key personnel in charge of excavating the shaft; placing the casing; placing slurry; placing the

steel reinforcing bars; and placing the concrete. DRILLED SHAFTS SECTION 606 207 d. The slurry manufacturer's representative.

e.The project engineer.

f.Inspection personnel.

2.If the contractor’s key personnel change, or if the contractor proposes a significant revision of

the approved drilled shaft installation plan, the engineer may request an additional drilled shaft preconstruction conference before performance of additional shaft construction operations.

F.Shaft Construction Logs.

1.Prepare inspection logs documenting each shaft construction activity, including casing

installation, excavation, shaft bottom inspection, reinforcement installation, and concrete placement. Document the work performed with frequent reference to the date , time, and casing or excavation elevation in the logs. Prepare and submit the logs documenting subsurface investigation borings or rock core holes performed for the contract at drilled shaft foundation locations.

2.Include the following information in the temporary and permanent casings records:

a.Identification number and shaft location;

b.diameter and casing wall thickness;

c.casing reinforcement dimensions;

d.top and bottom casing elevations;

e.casing installation method and equipment;

f.problems encountered during casing installation; and

g.name of inspector and the date, time, and name of any inspector changes.

3.In the shaft excavation log, include at least the following information:

a.Shaft identification number, location, and surface elevation;

b.description and approximate top and bottom elevation of each soil or rock material

encountered;

c.seepage or groundwater conditions;

d.type and dimensions of tools and equipment used and any changes to the tools and

equipment;

e.type of drilling fluid used and results of slurry tests;

f.problems encountered;

g.elevation of changes in the shaft diameter;

h.method used for bottom cleaning;

i.final bottom elevation of the shaft; and

j.name of the inspector and the date, time, and name of any inspector changes.

4.Include at least the following information in the concrete placement records:

a.Concrete mix used;

DRILLED SHAFTS SECTION 606 208 b. start and end times for concrete placement;

c.volume and start and end time for each truck load of concrete placed;

d.concrete test results;

e.concrete surface elevation and corresponding tremie tip elevation periodically during concrete

placement;

f.concrete yield curve consisting of volume versus concrete elevation, actual, and theoretical;

and

g.name of the inspector and the date, time, and name of any change of inspector personnel.

5.Submit the logs for each shaft construction activity to the engineer within 24 -hours of

completing the activity. Submit a full set of shaft inspection logs for an individually drilled shaft to the engineer within 48 -hours of completing shaft concrete placement.

G.Exploratory Drilling Plan

1.Submit an exploratory drilling plan for the engineer’s approval before drilling.

a.All drilling apparatus must be of sufficient size and capacity to carry on drilling operations in

an efficient manner and provide holes of adequate size. The minimum diameter of the hole must be 3 -inches into the bedrock. 606.3.2 Drilled Shaft Excavation.

A.When installing drilled shafts in conjunction with embankment construction, place the

embankment fill first unless otherwise shown in the contract, or approved by the engineer.

B.Excavate to the foundation cap elevation before beginning the drilled shaft, unless otherwise

noted in the contract, or approved by the engineer.

C.Once excavation begins, excavate in a continuous operation until completion, except for

interruptions and stops as noted below:

1.Interrupt excavation operation only for casing splicing and obstruction removal. The

Department will consider interruptions for anything other than these reasons as stops.

2.Excavation may stop if it is not possible to complete the drilled shaft by the end of the shift, or

series of continuous shifts, provided that the contractor protects the shaft as indicated in

3.When using slurry in shaft excavation and work stops, maintain a minimum level of drilling slurry

in accordance with Section 606.3.5.E. Recondition the slurry to the required slurry properties in accordance with Section 606.2.D before restarting shaft e xcavation.

D.The Department will allow drilled shaft excavation without excavation protection, provided the

contractor can demonstrate stability of the soil or rock above the water table and zones of seepage.

E.For excavation below the casing, perform sidewall over -reaming when the engineer determines

that the sidewall of the hole has softened due to excavation methods, has swelled due to delays in the start of concrete placement, or has degraded because of sl urry cake buildup. Over -ream a minimum of 1/2 -inch deep and a maximum of 3 inches deep. Over -ream with a grooving tool, over -reaming bucket, or other equipment approved by the engineer. DRILLED SHAFTS SECTION 606 209 F. Repair disturbances to the foundation cap area caused by shaft installation before placing the cap concrete.

G.Control operations to prevent damage to existing structures, utilities, roadways, and other

facilities in accordance with the drilled shaft installation plan. 606.3.3 Obstructions. Notify the engineer promptly when encountering obstructions during drilling. The Department considers specific objects as obstructions including boulders, logs, and man -made objects encountered during shaft drilling that prevent or hinder drilling. When ef forts to advance past the obstruction result in the significant reduction of progress, compared to progress made in drilling through the geological formation that contains the obstruction, remove, bypass, or break up the obstruction as force account work. 606.3.4 Drilled Shaft Excavation Protection.

A.Do not leave drilled shaft excavations open overnight or during stops unless the casing is full

depth or the shaft is otherwise protected against sidewall instability. The Department defines an open excavation as a drilled shaft not filled with concrete or temporarily backfilled with a material approved by the engineer such as slurry, in accordance with Section 606.3.1.C, or protected in accordance with Section 606.3.5.

B.The Department will not require casing of drilled shafts in stable rock formations during stoppages

unless required by the contract or specified here. 606.3.5 Drilled Shaft Excavation Protection Methods.

A.Protect the walls and bottom of the drilled shaft excavation to prevent side wall caving and

bottom heave and to avoid disturbance of the soil adjacent to the drilled shaft. Acceptable protection methods include the use of a casing, drilling slurry, or both.

B.Temporary Casing Construction Method.

1.In stable soils, conduct casing installation and removal operations, and drilled shaft excavation

operations so no disturbance occurs to the adjacent soil outside the casing for the full height of the drilled shaft. The Department defines disturbed soil as soil with geotechnical properties that have changed from the in -situ soil properties and the changes adversely affect the performance of the drilled shaft foundation.

2.The Department will allow excavation in soils below the water table with use of a sealed casing

in competent soils to prevent water from entering the excavation, provided the water level within the casing does not rise or exhibit flow.

3.During withdrawal of the temporary casing, maintain a sufficient head of fluid concrete to

ensure that water or slurry outside the temporary casing does not breach the column of freshly placed concrete.

4.Extract the casing by pulling in -line with the shaft axis. Avoid excessive rotation of the casing to

limit deformation of the reinforcing steel cage.

5.Remove temporary casings from the excavation after completing concrete placement, unless

the engineer approves of leaving the casings in place.

C.Permanent Casing Construction Method.

DRILLED SHAFTS SECTION 606 210 Install permanent casings using driving methods except when rotating, oscillating, or vibrating methods are specified in the contract and the approved drilled shaft installation plan.

D.Drilled Shafts Above Grade.

When the shaft extends above ground or through a body of water, the contractor may form that portion with a removable formwork except when specified for permanent casing. Strip the removable formwork from the shaft in a manner that does not damage the conc rete in accordance with Sections 604 and 610.3.7. Do not expose the shaft concrete to saltwater or moving water in accordance with Table 610.3 -4.

E.Slurry.

1.Use slurry in accordance with Section 606.2.D, to maintain a stable excavation during excavation

and concrete placement operations when:

a.Water begins to enter the drilled shaft excavation at a rate of greater than 12 inches per hour;

b.it becomes impossible to restrict the amount of water in the drilled shaft to less than 3 -inches

before concrete placement; or

c.water pressure needs equalizing on the sides and base of the drilled shaft excavation when

encountering or anticipating groundwater based on the available subsurface data.

2.Slurry Sampling and Testing.

a.Mix and hydrate mineral slurry and polymer slurry in slurry tanks, lined ponds, or storage

areas. Draw sample sets from the slurry storage facility and test the samples for conformance with the appropriate specified material properties before beginning slurry placement in the drilled hole. Ensure that the slurry conforms to the quality control plan included in the drilled shaft installation plan and in accordance with Section 606.3.1.C. Provide samples taken at mid - height and within 2 -feet of the bottom of the storage area.

b.Sample and test slurry in the engineer’s presence, unless otherwise approved by the engineer.

Record the date, time, names of the persons sampling and testing the slurry, and the test results. Submit a copy of the recorded slurry test results to the eng ineer at the completion of each drilled shaft and during construction of each drilled shaft when requested.

c.Take and test slurry samples during drilling to verify control of slurry properties. At a

minimum, take and test the sample sets of slurry at least once every 4 -hours after beginning use during each shift.

d.Take and test sample sets of slurry immediately before placing concrete.

3.Slurry Technical Assistance.

a.When using slurry, the manufacturer's representative, as identified to the engineer in

accordance with Section 606.3.1.D, must:

i.Provide technical assistance for use of the slurry.

ii. Be present at the site before placing slurry in a drilled hole. iii. Remain at the site during construction and completion of a minimum of 1 drilled shaft to adjust the slurry mix to the specific site conditions.

b.When the manufacturer’s representative leaves the site, provide an employee trained in the

use of the slurry, as identified to the engineer in accordance with Section 606.3.1.D. Ensure DRILLED SHAFTS SECTION 606 211 that the employee is present at the site throughout the remainder of shaft slurry operations performing the duties specified above.

4.Minimum Level of Slurry in the Excavation.

a.Maintain the slurry level at a height required to provide and maintain a stable hole, but no less

than 5 -feet above the water table or surface of surrounding body of water, if at an offshore location.

b.Provide casing, or other means, as necessary to meet these requirements.

c.Maintain the slurry level above all unstable zones at a sufficient distance to prevent bottom

heave, caving, or sloughing of those zones.

i.Throughout all stops in drilled shaft excavation operations, monitor and maintain the slurry

level in the excavation so that it is no lower than the water level elevation outside the drilled shaft or the elevation required to provide and maintain a stable hole.

5.Cleaning Slurry

a.Clean, re -circulate, de -sand, or replace the slurry, as needed, to maintain the required

properties. Ensure that sand content is within the specified limits immediately before concrete placement. 606.3.6 Drilled Shaft Excavation Inspection.

A.Clean the bottom of the excavations of drilled shafts. The Department will not allow more than 3 -

inches of sediment or loose or disturbed material at the bottom of the drilled shaft excavation, in soil shafts, or more than 1/2 -inch for 50 percent of the shaft bottom area in rock sockets before placing concrete. Refer to Section 606.3.10 for allowable sidewall tolerances.

B.To determine that the drilled shaft bottom and sidewalls are in accordance with the contract,

inspect the bottom and sidewalls of the shaft with an airlift pipe, a tape with a heavy weight attached to the end of the tape, a borehole camera with visuals ediment depth measurement gauge, or other means acceptable to the engineer. Do not continue with drilled shaft construction until receiving an approval from the engineer.

C.If the engineer determines that stable conditions do not exist, immediately stabilize the shaft.

Submit a revised drilled shaft installation plan that addresses the problem and prevents future instability. Do not continue with drilled shaft construction until repair of the instability, in accordance with the specifications, and until receiving the engineer's approval of the revised drilled shaft installation plan. 606.3.7 Rock Sockets. The Department considers rock sockets as drilled shafts in rock. Construct rock sockets in accordance with the contract. For the Department to consider excavated material as rock, the material must qualify as geomaterial having an unconfined compressive st rength equal to or greater than 725 -PSI that conventional earth augers or under reaming tools cannot drill requiring use of rock augers, core barrels, air tools, and other excavation methods. 606.3.8 Reinforcing Steel Assembly and Placement.

A.Fabricate and handle the steel reinforcing cage in accordance with Section 611.

B.Brace the steel reinforcing cage to retain its configuration during handling and construction. Tie

intersections of vertical and horizontal bars. DRILLED SHAFTS SECTION 606 212 C. Position and fasten the steel reinforcement to provide the minimum clearances in accordance with the contract to ensure no displacement of the steel reinforcing cage occurs during concrete placement.

D.Bundle vertical bars when necessary to maximize clear space between vertical reinforcement bars.

Use rolled hoops or bundled spirals when necessary to maximize clear space between horizontal reinforcement.

E.Do not splice the steel reinforcement cage during placement in the shaft excavation, unless

otherwise shown in the contract or approved by the engineer.

F.If the engineer allows splicing of the steel reinforcing cage during placement in the drilled shaft,

ensure that the splice details and location of the splices are in accordance with the contract and the approved drilled shaft installation plan.

G.Hold the steel reinforcing cage in position throughout the concrete placement operation. Support

the reinforcing steel in the drilled shaft so that the location of the reinforcing steel will remain within allowable tolerances in accordance with Section 606.3.10. Use concrete spacers or other approved non -corrosive spacing devices near the bottom and the top and at intervals not exceeding 10 -feet vertically. Provide 1 spacer per foot of excavation diameter with a minimum of 4 spacers in each group of spacers. Use spacers to ensure concentric spacing between the outside of the steel reinforcing cage and the side of the excavation along the entire length of the drilled shaft. Provide bottom supports made of plastic, or concrete to ensure that the bottom of t he cage remains at the proper distance above the bottom of the excavation, unless the cage is suspended above the base during the concrete pour.

H.Remove bracing steel that may constrict the interior of the reinforcing cage after lifting the cage.

I.Check the top elevation of the steel reinforcing cage before and after concrete placement. If the

location of steel reinforcing cage is outside the tolerances specified in Section 606.3.10, the Department will consider the result a defective drilled sha ft. Make corrections to the engineer’s satisfaction. Do not construct additional drilled shafts until after making modifications of the steel reinforcing cage support that satisfy the engineer. 606.3.9 Concrete Placement, Curing , and Protection.

A.Begin concrete placement as soon as possible after completing the drilled shaft excavation and

approval by the engineer. Continue the concrete placement in 1 operation to the top of the drilled shaft, or as shown in the contract. Cure exposed drilled shaft surfaces in accordance with Section 501.3 with materials in accordance with Section 1022.6.

B.Use only the concrete mix design approved for use and included with the approved drilled shaft

installation plan. Adjust all admixtures, when approved for use, for the conditions encountered so the concrete remains in a workable plastic state throughout placement.

C.Before concrete placement, provide test results of both a trial mix and a slump loss test,

conducted by an approved testing laboratory to demonstrate that the concrete meets the defined placement time limit. Conduct the trial mix and slump loss tests at ambient temperatures appropriate for site conditions.

D.Place concrete continuously until completing the work, resulting in a seamless, uniform shaft.

1.Place the concrete by tremie methods in accordance with Section 610.3.4.D.2.

DRILLED SHAFTS SECTION 606 213 2. Adhere to the time limit for concrete placement, as defined in the approved drilled shaft installation plan, and demonstrated by a successful technique shaft. Start concrete placement time at the mixing of concrete and extend through to the completion of placement in the drilled shaft excavation, including time for removing temporary casings.

3.Place concrete when the ambient air temperature matches ambient air temperature that

existed during the concrete trial tests and slump loss tests.

E.Complete a concrete yield plot for each shaft. Submit a yield plot to the Department within 24 -

hours of completing the concrete pour.

F.Do not perform casing installation or drilled shaft excavation operations within a distance of 3

diameters of a newly poured drilled shaft within 24 -hours of concrete placement in the newly poured drilled shaft or before the concrete in the newly poured drilled shaft reaches a minimum compressive strength of 1,800 -PSI. 606.3.10 Drilled Shaft Construction Tolerances.

A.Construct drilled shafts so that the center of the poured shaft at the top of the drilled shaft or

mudline, whichever is lower, is within the following horizontal tolerances as shown in Table 606.3 -2: Table 606.3 -2. Horizontal Tolerances for Drilled Shafts Drilled Shaft Diameter Tolerance Greater than 24 inches and less than 60 inches 4 inches 60 inches or larger 6 inches

B.The tolerance for drilled shafts in soil is within 1.5 percent of plumb. The tolerance for drilled

shafts in rock is within 2 percent of plumb. Measure plumb from the top of the poured drilled shaft elevation, or mudline, whichever is lower.

C.During drilling or excavation, make frequent checks on plumb, alignment, and dimensions of the

drilled shaft. Submit a procedure for correcting deviations exceeding the allowable tolerances. Correct deviations in accordance with the approved procedure.

D.Ensure that drilled shaft steel reinforcing bars do not extend 6 inches above, or 3 -inches below,

the elevation shown in the contract.

E.The shape of the reinforcing cage must share concentric properties with the drilled shaft

excavation, within a tolerance of 1 1/2-inches.

F.Ensure that the top elevation of the completed drilled shaft is within a tolerance of plus 1 -inch or

minus 3 -inches.

G.Match the drilled shaft diameter to the diameter shown in the contract.

H.Ensure that tolerances for casings are in accordance with the ASTM designation in Section 606.2.C

unless otherwise noted in the contract.

I.The Department will consider drilled shaft excavations and completed drilled shafts not meeting

the specified tolerances as defective. Correct defective drilled shafts to the satisfaction of the DRILLED SHAFTS SECTION 606 214 engineer. Submit redesign drawings and computations for correcting the defects, signed by a professional engineer in the State of Delaware. 606.3.11 Non -Destructive Testing.

A.For bridges, perform Thermal Integrity Profiling (TIP), Method B and Crosshole Sonic Log (CSL)

testing on all drilled shafts in accordance with ASTM D7949 and ASTM D6760. For all other structures, perform either TIP or CSL testing at the contractor’s discretion on all drilled shafts in accordance with ASTM D7949 or ASTM D6760.

B.For TIP, Method B, attach thermal wire cables to the longitudinal reinforcement of the shaft using

nylon zip -ties at 1 1/2 to 2-inches from the top and bottom of each node. Provide and install 1 thermal wire cable for each foot of drilled shaft diameter, rounded to the nearest whole number, unless otherwise shown in the contract. Place a minimum of 3 thermal wire cables for each shaft. Attach each thermal wire cable to a data logger with the data logger suspended on a protruding rebar well above the top of the concrete. If the cable is routed with a bend at any location, take extra precautions on securing the cable with zip -ties on either side of each such node.

1.Connect thermal wire cables to a data logger immediately following casting of concrete. Make

note of which cable is connected to which data logger. The data logger will collect data at 15 - minute intervals for 24 -hours or for a duration approved by the engineer. In the event peak temperature is not reached within the specified time period, the data logger units will remain connected to the thermal wire cables for a longer duration as directed by the engineer. After completion of the data collection period , connect the data logger to the main TIP data acquisition unit and download the data files for analysis of temperatures versus depth.

2.Immediately report to the engineer any potential local defects indicated by locally low

temperatures relative to the average temperature at that depth, or average temperatures significantly lower than the average temperatures at other depths.

3.Submit a report of the TIP testing results and analysis to the engineer within 7 calendar days of

testing completion. The report shall include:

a.Graphical displays of all temperature measurements versus depth.

b.Indication of unusual temperatures, particularly of significantly cooler local deviations of the

average at any depth from the overall average over the entire length.

c.The overall average temperature. This temperature is proportional to the average radius

computed from the actual total concrete volume installed assuming a consistent concrete mix throughout. The temperature at that point compared to the overall average temperature can determine the radius at any point.

d.Variations in temperature between thermal wire cables at each depth, which in turn

correspond to variations in cage alignment. Where concrete volume is known, note the cage alignment or offset from center.

C.Accommodate the CSL testing by providing and installing access tubes.

1.Install access tubes for cross -hole sonic log testing in all drilled shafts, except as otherwise

noted, to allow access for the CSL test probes. If, in the opinion of the engineer, the condition of the drilled shaft excavation permits drilled shaft cons truction in the dry, the engineer may allow cancellation of the testing. DRILLED SHAFTS SECTION 606 215 2. Attach access tubes to the interior of the reinforcement cage. Provide and install 1 access tube for each foot of drilled shaft diameter, rounded to the nearest whole number, unless otherwise shown in the contract. Place a minimum of 3 tubes. Place the access tubes around the drilled shaft, inside the spiral or hoop reinforcement, and 3 -inches clear of the vertical reinforcement, at a uniform spacing measured along the circle passing through the centers of the access tubes. If these minimums do not occur , due to close spacing of the vertical reinforcement, bundle the access tubes with the vertical reinforcement.

3.If required to trim the cage, and access tubes for CSL testing are attached to the cage, shift the

access tubes up the cage or cut the access tubes. Provide watertight caps for the cut tube ends.

4.Install access tubes in a straight alignment and as near to parallel to the vertical axis of the

reinforcement cage as possible. Extend the access tubes from the bottom of the drilled shaft to at least 2 -feet above the top of the drilled shaft. Splice joints in the access tubes, if required, to achieve full -length access tubes. Ensure a watertight fit. Clear the access tubes of debris and extraneous materials before installing.

5.Fill the access tubes with potable water, before concrete placement, and install watertight,

threaded caps.

6.Before performing CSL testing operations, remove the concrete at the top of the drilled shaft

down to sound concrete.

7.After placing the drilled shaft concrete, and before beginning the CSL testing of a drilled shaft,

inspect the access tubes and replace tubes a test probe cannot pass through. To replace a tube, core a 2 -inch diameter hole through the concrete for the e ntire length of the shaft. Unless directed otherwise by the engineer, locate the cored holes approximately 6 -inches inside the reinforcement. Log descriptions of inclusions and voids in cored holes and submit a copy of the log to the engineer. Preserve fin dings from cored holes, identified by location, and make available for inspection by the engineer.

8.Perform testing at least 96 -hours after the drilled shaft concrete has cured. Allow additional

curing time before testing if the drilled shaft concrete contains admixtures, such as a set retarding admixture or a water -reducing admixture.

D.The engineer will determine final acceptance of each drilled shaft based on the required non -

destructive testing results and analysis for the tested shafts and a review of the visual inspection reports for the subject drilled shaft. The engineer will pr ovide a response to the contractor within 5 calendar days after receiving the test results and analysis submittal.

1.If the contract does not require technique shafts, the engineer may approve continuing with

other drilled shafts before approval and acceptance of the first production shaft if:

a.The engineer observes that construction of the first production shaft was satisfactory.

b.The contractor placed the first production shaft in accordance with the drilled shaft

installation plan.

c.A review of contractor’s daily reports and inspector’s daily logs concerning excavation,

reinforcing steel placement, and concrete placement caused no concerns.

2.If the engineer determines that concrete placed under slurry for a given drilled shaft is

structurally inadequate, the engineer will reject the drilled shaft. The engineer will not allow further placement of concrete under slurry until the contractor su bmits written changes to the DRILLED SHAFTS SECTION 606 216 construction methods to prevent future structural inadequacies. Obtain the engineer's written approval of the submittal before beginning additional drilled shafts.

3.Based on the test results, the engineer may determine that additional investigation of a

completed drilled shaft is necessary. The contractor may also request additional testing. At the engineer's request, core a hole as determined from non -destructive testing and analysis, to explore the drilled shaft condition.

a.Before beginning coring, submit the method and equipment used to drill and remove cores

from drilled shaft concrete to the engineer. Do not begin coring until receipt of the engineer’s written approval.

b.The engineer will determine the number, locations, diameter, and depth of the core holes,

and lengths of individual core runs. Ensure that coring procedures minimize abrasion and erosion of the core samples and avoid damage to the steel reinforcement. L og descriptions of inclusions and voids in cored holes and submit a copy of the log to the engineer. Recover the complete core. Preserve the recovered core in labeled wood core boxes, identified by location and depth, and make available for inspection by t he engineer. The engineer may direct water - pressure testing in the core holes, or unconfined compression testing and other laboratory testing on selected samples from the concrete core.

4.If the additional testing indicates that the drilled shaft has no defects, the Department will take

responsibility for the testing and delay costs. If the drilled shaft construction is on the critical path of the contractor’s schedule, the Department wi ll grant a time extension equal to the delay created by the additional testing.

5.For all unacceptable drilled shafts, submit a plan for further investigation or remedial action to

the engineer for approval. Calculations and working drawings must support all modifications to the drilled shaft dimensions required by the investigation and the remedial action plan. Use a registered engineer in the State of Delaware to prepare the investigation and remedial correction procedures and designs and submit to the engineer for approval. Do not begin repair operations until receipt of the engineer's written approval of the investigation and remedial action plan.

E.Dewater access tubes and cored holes and fill with grout after completion of tests and acceptance

of the drilled shaft. Fill the access tubes and cored holes using grout tubes that extend to the bottom of the tube, or hole, or into the grout already pla ced.

F.The contract may specify alternative non -destructive tests such as gamma -gamma, sonic

echo/impulse response (ASTM D5882), or other tests the engineer may direct the contractor to use alongside, or instead of, TIP or CSL testing. Comply with all requirem ents for the alternate test methods, in accordance with the contract. 606.3.12 Technique Shafts.

A.Demonstrate the adequacy of the methods, techniques, and equipment by successfully

constructing a technique shaft or shafts in accordance with the contract. Position the technique shafts at the locations shown in the contract, or as directed by the engi neer, but no less than a distance of 3 drilled shaft diameters from the closest production shaft. Drill the technique shafts to the maximum diameter and maximum depth of any production drilled shaft shown in the contract. Reinforce the technique shafts wit h the same reinforcement as the corresponding size production shaft, and include TIP thermal wire cables, CSL access tubes, and load testing devices as specified in the contract. DRILLED SHAFTS SECTION 606 217 B. Obtain the engineer’s acceptance of the completed technique shafts before installing production drilled shafts. Failure to demonstrate the adequacy of its methods and equipment may result in the engineer requiring the contractor to submit a plan to modi fy its methods and equipment to eliminate unsatisfactory results.

C.Once the engineer approves construction of production drilled shafts, make no changes in the

methods or equipment used to construct the technique shaft without the engineer’s written approval.

D.The engineer will use the technique shafts to determine the contractor’s ability to:

1.Control dimensions and alignment of excavations within tolerance;

2.install and remove temporary casings;

3.control the size of the excavation under caving conditions;

4.clean the completed drilled shaft excavation;

5.construct drilled shafts in open water areas;

6.handle and place reinforcing cages;

7.place concrete meeting the specification requirements within the prescribed time limit;

8.perform non -destructive and load testing; and

9.execute other necessary construction operations.

E.When authorized in writing by the engineer, cut off the technique shafts no less than 2 -feet below

finished grade and leave in place. Restore the disturbed areas at the sites of the technique shafts as nearly as practical to the original condition. 606.3.13 Drilled Shaft Load Tests.

A.Perform load tests on technique or production shafts at the locations shown in the contract unless

otherwise directed or approved by the engineer.

B.If the equipment or procedures change following completion of load testing, conduct additional

load tests as directed by the engineer on a replacement technique or production shaft.

C.Complete load testing and have the results evaluated by the engineer before placing production

drilled shafts, unless otherwise authorized by the engineer.

1.Perform static load tests in accordance with ASTM D1143.

2.Perform force pulse (rapid) load tests in accordance with ASTM D7383.

3.For bi -directional load cell testing, install load cells and load test instrumentation in accordance

with the bi -directional load cell supplier recommendations. Ensure that the bi -directional load cells are capable of expanding to no less than 6 inches while maintaining the applied test load.

a.Coordinate with the load cell supplier to determine required equipment, materials, quantities,

procedures, and all other applicable items needed to complete the load testing shown in the contract.

b.Provide a pressurized gas source, a hydraulic pump, hydraulic lines, calibrated hydraulic

gauge, and other equipment and material necessary to perform the load tests. Provide DRILLED SHAFTS SECTION 606 218 potable water from an approved source to form the hydraulic fluid used to pressurize the bi - directional load cells.

c.Provide, install, and monitor vibrating wire strain gauges as shown in the contract. Place the

strain gauges in pairs on opposite sides of the reinforcing cage at the elevations shown in the contract, unless otherwise directed by the engineer.

d.Attach 2 Linear Variable Differential Transformers (LVDT) vibrating wire displacement gauges

to each load cell to monitor the load cell expansion and contraction. Mount 2 LVDT gauges on an independent reference beam and set on opposite sides of the top of the load tested shaft to monitor axial shaft displacement.

e.Set 2 telltale rods on the top of each load cell to monitor displacement of the top of the load

cell. Provide a telltale consisting of a 3/8 -inch diameter stainless steel greased rod placed inside a constant 3/4 -inch diameter pipe. Individual sections o f telltales will have joint -coupled flush so that each rod is of uniform diameter throughout its length.

f.Provide a portable computer and electronic logging equipment to simultaneously monitor all

instrumentation at time intervals designated by the engineer.

g.Assemble the load cells, piping, and other attachments in preparation for installation in

accordance with the requirements of the bi -directional load cell supplier, unless otherwise specified here.

h.Mandatory guidelines:

i.Weld steel top and bottom bearing plates to the load cells in accordance with Section 615 .

Provide holes through the bearing plates to facilitate placement of tremie concrete. ii. Coat the upper surface of the bottom steel bearing plate with grease before installing in the shaft to prevent concrete bonding with the bottom plate. iii. Attach the load cells and plate assembly to the reinforcement cage. Fasten all hydraulic hoses, telltale casing, and slip joints to the rebar cage. Before installing in the drilled shaft excavation, protect the top of any piping to keep dirt, concrete , or other materials from entering the piping. iv. Limit cage deflection to a maximum of 2 -feet between pick points while lifting the cage from the horizontal position to vertical. Provide support to maintain deflection within the specified tolerance.

i.For each load test, place the load on the drilled shaft in increments of 5 percent of the

estimated maximum test load shown in the contract, or until the nominal resistance load occurs, indicated by the instruments, or to the maximum capacity of the loa d cell, whichever occurs first. Unless the maximum capacity of the load cell occurs, apply increments of 2.5 percent of the estimated maximum test load until attaining the limiting load or the drilled shaft top displacement reaches 2 -inches, or to the maxi mum extension of the load cell. When using the load cell for a subsequent loading stage, the engineer may interrupt the loading sequence at a load cell opening of approximately 3 -inches, or less. Maintain each load increment for a minimum period of 5 -minutes, with complete sets of readings obtained and recorded from all gauges and instruments at 1, 2, and 5 minutes after application of the load increment. Apply each increment of load within the minimum length of time practical, with maximum of 15 -minutes, a nd take the instrument system readings immediately. The engineer may elect to hold the maximum applied load for up to 1 -hour. DRILLED SHAFTS SECTION 606 219 j. Remove the load in decrements of approximately 10 percent of the maximum test load. Remove each decrement of load within the minimum length of time practical and take the instrument system readings immediately. Complete removal of a load decrement and t he completion time frame of the instrument readings within 5 to 15 minutes. The engineer may also require a reloading cycle with 10 loading increments and 5 unloading decrements. Record the final recovery of the drilled shaft for a period up to 1 -hour afte r the last unload interval.

k.Submit a preliminary test report containing the load displacement curves, and other test data

within 5 calendar days of completing each load test. Submit the final report on the load tests within 14 calendar days after completing each load test. Include at least the following items in the test report:

i.Shaft identification number and location;

ii. Testing dates; iii. Description of the shaft details, instrumentation, and test procedures; iv. Tables presenting all instrumentation data;

v.Plots of load versus displacement, up and down, for each load cell level, for each stage of

the test; vi. Plots of load along the length of the drilled shaft determined from the strain gauge data for at least ten applied load increments; vii. Summary of unit side resistance along the length of the drilled shaft and end bearing resistance; viii. Plots of creep displacement for each load increment; and ix. Plot of equivalent top -of-shaft displacement for the load tested shaft, developed from the load test data.

l.After completing the load test to the engineer’s satisfaction, and when authorized in writing by

the engineer, flush all hydraulic fluid from the bi -directional load cells and hydraulic lines, and replace with cement grout in accordance with the approve d drilled shaft installation plan. Grout all voids remaining outside the load cells after completing the load test. 606.3.14 Exploratory Drilling.

A.Confirm the top of rock elevation and characterize the approximate rock quality designation of the

drilled bedrock.

B.Drill at locations in accordance with the contract or as specified by the engineer.

C.Perform air track drilling in the presence of the engineer using drilling apparatus in the exploratory

drilling plan. Advance the hole through the overburden without sampling.

D.Ensure that the drilled hole is vertically plumb and open throughout drilling operations. Support

the hole as necessary with casings advanced by driving or jacking. Seat the casing tightly in the bedrock. The casing is temporary and may be withdrawn or left in place before grouting.

E.Notify the engineer if drilling encounters unique subsurface features such as soft zones, soil

seams, or voids. Drill a minimum of 10 feet of continuous rock below the top of bedrock or bottom of shallow or deep foundation in the footprint of the explor atory drilling location, whichever is deeper. DRILLED SHAFTS SECTION 606 220 F. Grout the drilled holes to the top of the drilled elevation . Use grout materials in accordance with DNREC's 7301 Regulations Governing the Construction and Use of Wells, Section 5.8.12.1 . Do not begin grouting the drilled holes until completing drilling of all locations.

G.Submit an exploratory drilling log for each location within 48 hours of completing the final drilled

hole. Include the following in the logs:

1.Depth of the overburden and rock penetrated;

2.methods used to advance the hole;

3.methods used to advance the casings;

4.length of casings installed;

5.location and depth of any unique subsurface features;

6.depths of loss of air pressure with its associated elevation;

7.tabulation of time per foot of penetration for the full drilled depth; and

8.approximate rock quality designation

606.4Method of Measurement.

A.The Department will measure:

1.Drilled shafts in soil by the length in linear feet from the plan top of shaft in soil elevation to the

final bottom of shaft in soil elevation. The Department will not separately measure excavation, blasting, slurry, reinforcing steel, concrete, grout, or non -destructive testing.

2.Technique shafts by the length in linear feet from the existing ground surface elevation at the

center of the technique shaft hole before drilling to the authorized bottom elevation of the hole. The Department will not separately measure excavation, bla sting, slurry, reinforcing steel, concrete, grout, or non -destructive testing.

3.Permanent casing by the length in linear feet of each size casing provided and installed.

4.Drilled shafts in rock by the length in linear feet from the top of rock elevation to the final

bottom of shaft in rock elevation. The Department will not separately measure excavation, blasting, slurry, reinforcing steel, concrete, grout, or non -destru ctive testing.

5.Load tests by the number of load tests completed according to the specified loading procedures

and to the designated maximum load shown in the contract.

6.Exploratory drilling by the length in linear feet from the ground elevation where the drilling

begins to the bottom of the exploration hole. The Department will not separately measure grout or temporary casings to maintain an open bore hole.

606.5Basis of Payment.

A.Payment includes full compensation for excavation of soil and rock, blasting, slurry, reinforcing

steel, concrete, concrete curing, grout, non -destructive testing, and all other required Work.

B.Payment includes full compensation for providing and placing the permanent casing.

C.Payment includes full compensation for performance of the load test and for reporting of

procedures and results. DRILLED SHAFTS SECTION 606 221 D. Payment includes full compensation for exploratory drilling and for grout, temporary casings, and results.

E.The Department will pay for efforts to advance past an obstruction that results in the significant

reduction of progress, compared to progress made in drilling through the geological formation that contains the obstruction, and the work to remove, bypass, or break up an obstruction using the Force Account provisions in Section 109. DRILLED SHAFTS SECTION 606 222 ITEM DESCRIPTION UNIT 606000 DRILLED SHAFT IN SOIL, 30" DIAMETER LF 606001 DRILLED SHAFT IN SOIL, 36" DIAMETER LF 606002 DRILLED SHAFT IN SOIL, 42" DIAMETER LF 606003 DRILLED SHAFT IN SOIL, 48" DIAMETER LF 606004 DRILLED SHAFT IN SOIL, 60" DIAMETER LF 606005 DRILLED SHAFT IN SOIL, 72" DIAMETER LF 606006 DRILLED SHAFT IN SOIL, 54” DIAMETER LF 606007 DRILLED SHAFT IN SOIL, 66” DIAMETER LF 606010 TECHNIQUE SHAFT, 30" DIAMETER LF 606011 TECHNIQUE SHAFT, 36" DIAMETER LF 606012 TECHNIQUE SHAFT, 42" DIAMETER LF 606013 TECHNIQUE SHAFT, 48" DIAMETER LF 606014 TECHNIQUE SHAFT, 60" DIAMETER LF 606015 TECHNIQUE SHAFT, 54" DIAMETER LF 606016 TECHNIQUE SHAFT, 66” DIAMETER LF 606017 TECHNIQUE SHAFT, 72” DIAMETER LF 606020 PERMANENT CASING FOR DRILLED SHAFT, 30" DIAMETER LF 606021 PERMANENT CASING FOR DRILLED SHAFT, 36" DIAMETER LF 606022 PERMANENT CASING FOR DRILLED SHAFT, 42" DIAMETER LF 606023 PERMANENT CASING FOR DRILLED SHAFT, 48" DIAMETER LF 606024 PERMANENT CASING FOR DRILLED SHAFT, 60" DIAMETER LF 606025 PERMANENT CASING FOR DRILLED SHAFT, 72" DIAMETER LF 606026 PERMANENT CASING FOR DRILLED SHAFT, 54” DIAMETER LF 606027 PERMANENT CASING FOR DRILLED SHAFT, 66” DIAMETER LF 606030 LOAD TESTING OF DRILLED SHAFTS EACH 606031 EXPLORATORY DRILLING LF 606040 DRILLED SHAFT IN ROCK, 24” DIAMETER LF 606041 DRILLED SHAFT IN ROCK, 30” DIAMETER LF 606042 DRILLED SHAFT IN ROCK, 36” DIAMETER LF 606043 DRILLED SHAFT IN ROCK, 42” DIAMETER LF 606044 DRILLED SHAFT IN ROCK, 48” DIAMETER LF 606045 DRILLED SHAFT IN ROCK, 54” DIAMETER LF 606046 DRILLED SHAFT IN ROCK, 60” DIAMETER LF 606047 DRILLED SHAFT IN ROCK, 66” DIAMETER LF

Source: Delaware Standard Specifications for Road and Bridge Construction, 2025 Edition. Pages 212–232 of 779.

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60519 3 INSTALL PRECAST PRESTRESSED CONCRETE TEST PILES, 18" X 18" LF

60600 0 DRILLED SHAFT IN SOIL, 30" DIAMETER LF