ITEM 400 – PILING
400.1 Description
400.1.1 Scope
This Item shall consist of piling, furnished, driven or placed, cut and
spliced in accordance with this Specification and in reasonably close
conformity with the Plans.
The Contractor shall furnish the piles in accordance with an itemized list,
which will be provided by the Engineer, showing the number and lengths of
all piles. When cast-in-place concrete piles are specified on the Plans,
the Engineer will not furnish the Contractor an itemized list showing the
number and length of piles. When test piles and load tests are required in
conformance with Sub-section 400.1.2 and 400.1.3, respectively, the data
obtained from driving test piles and making test loads will be used in
conjunction with other available sub-soil information to determine the
number and lengths of piles to be furnished. The Engineer will not prepare
the itemized list of piles for any portion of the foundation area until all
specified loading tests in the Contract representative of the portion have
been completed.
In determining lengths of piles for ordering and to be included for
payment, the lengths given in the order list will be based on the lengths
which are assumed to remain in the completed structure. The Contractor,
shall, without added compensation, increase the lengths to provide for the
fresh heading and for such additional length as maybe necessary to suit the
Contractor’s method of operation.
400.1.2 Test Piles
For his own information, the Contractor may drive at the location of the
regular piles indicated on the Plans such test piles as he may consider
necessary in addition to the test piles specified in the Contract and shall
be considered as regular piles. When called for in the Bill of Quantities,
a pile if required to be subjected to load test shall conform to the
provision as provided in Subsection 400.1.3, Load Tests. The Contractor
shall furnish and drive test piles of the dimensions and at the locations
designated by the Engineer. They shall be of the material shown in the Bill
of Quantities and shall be driven to refusal or to such tip elevation or
approximate bearing value as the Engineer may request. Test piles shall be
driven with the same hammer that is used for driving foundation piles.
When the Engineer requests a load test to determine a bearing value, the
first load test pile shall be driven to the specified bearing value as
determined by the applicable formula in Subsection 400.1.4 for Timber Pile
Bearing Value by Formula. Subsequent test piles to be load-tested shall be
driven to the specified bearing value as determined by the applicable
formula modified by the results of prior test loads and foundation data.
The ground at each test pile shall be excavated to the elevation of the
bottom of the footing before the pile is driven.
400.1.3 Load Tests
Load tests for files shall be either Static or Pile Testing by Low-Strain
Dynamic Method, High-Strain Dynamic Method and Cross-Hole Sonic Logging.
When load tests are specified, the number and location of piles to be
tested will be designated by the Engineer. Load tests shall be done by
methods approved by the Engineer. The Contractor shall submit to the
Engineer for approval detailed plans of the loading apparatus he intends to
use. The apparatus shall be so constructed as to allow the various
increments of the load to be placed gradually without causing vibration to
the test piles. If the approved method requires the use of tension (anchor)
piles, such tension piles shall be of the same type and diameter as the
permanent piles and shall be driven in the location of permanent piles when
feasible. Piling not a part of the structure shall be removed or cut off at
least 300mm below the bottom of the footing or finished elevation of the
ground upon completion of the test load. Permanent piling used as anchor
piling which is raised during the test load shall be red riven to original
grade and bearing.
400.1.3.1 Static Testing
Suitable approved apparatus for determining accurately the load on pile and
the settlement of the pile under increment of load shall be supplied by the
Contractor.
Test loading shall consist of the application of incremental static loads
to a pile and measuring the resultant settlement. The loads shall be
applied by a hydraulic jack acting against suitable anchorage, transmitting
the load directly to the pile, or other methods designated by the Plans or
approved by the Engineer.
The load shall be applied in increments of 5 or 10 tonnes as directed by
the Engineer. Gross settlement readings, loads and other data shall be
recorded by the Engineer immediately before and after the applications of
each load increment.
Each load increment shall be held for an interval of two and one-half
minutes. Each succeeding increment shall be as directed by the Engineer or
as shown on the Plans and shall be applied immediately after the two and
one-half minute interval readings have been made.
When a load-settlement curve obtained from these data shows that the pile
has failed; i.e., the load can be held only by the constant pumping and the
pile or shaft is being driven into the ground, pumping shall cease. Gross
settlement readings, loads and other data shall be recorded immediately
after pumping has ceased and again after an interval of two and one-half
minutes for a total period of five (5) minutes. All loads shall then be
removed and the member allowed to recover. Gross settlement readings shall
be made immediately after all loads have been removed and at each interval
of two and one-half minutes for a total period of five (5) minutes.
All load tests shall be carried to failure or to the capacity of the
equipment, unless otherwise noted on the Plans.
After the completion of loading tests, the load used shall be removed and
the piles including tension piles, shall be utilized in the structure if
found by the Engineer to be satisfactory for such use. Test piles not
loaded shall be utilized similarly. If any pile, after serving its purpose
as a test or tension pile, is found unsatisfactory for utilization in the
structure, it shall be removed if so ordered by the Engineer or shall be
cut off below the ground line of footings, whichever is applicable.
When diesel or other types of hammers requiring calibration are to be used,
the Contractor shall make load tests even though no load tests are called
for in the Bill of Quantities, except that load tests will not be required
when the hammer is to be used only for driving piles to refusal, rock or a
fixed tip elevation or the hammer is of a type and model that has been
previously calibrated for similar type, size and length of pile, and
foundation material. Calibration data must have been obtained from sources
acceptable to the Engineer.
400.1.3.2 Pile Testing
Pile testing shall be done by Low-Strain Dynamic Method, High-Strain
Dynamic Method or Cross-Hole Sonic Logging Method as required in the plans
or as directed by the Engineer.
400.1.3.2.1 Low-Strain dynamic Method
Pile integrity testing by Low-Strain Dynamic Method shall conform to
ASTMD-5882-96. It is a so-called Low Strain Method, since it requires the
impact of only a small hand-held hammer, and also referred to as a
Non-Destructive Method.
400.1.3.2.2 High-Strain Dynamic Testing
Pile Integrity testing by High-Strain Dynamic Method shall conform to ASTM
D4945-97. High-Strain Dynamic Method shall be applied to confirm the design
parameters and capacities assumed for the piles as well as to confirm the
normal integrity of testing of the piles. It is considered supplemental to
the low-strain and sonic-type integrity testing of the cast-in-place piles.
It is a non-destructive relatively quick test and it is intended that the
test shaft be left in a condition suitable for use in production. The shaft
used for the test will be instrumented and tested by the testing
specialist, as approved by the Engineer, meeting requirements in accordance
to ASTM D4945-97.
400.1.3.2.3 Cross-Hole Sonic Logging of Bored Holes
By sending ultrasonic pulses through concrete from one probe to another
(probes located in parallel tubes), the Cross-hole Sonic Logging (CSL)
procedure inspects the drilled shaft structural integrity, and extent and
location of defects, if any. At the receiver probe, pulse arrival time and
signal the concrete affects strength. For equidistant tubes, uniform
concrete yields consistent arrival times with reasonable pulse wave speed
and signal strengths. Non – uniformities such as contamination, soft
concrete, honeycombing, voids, or intrusions of foreign objects exhibit
delayed arrival time with reduced signal strength.
400.1.4 Timber Pile Bearing Value by Formula
When load tests are called for in the Bill of Quantities and when diesel or
other hammers to be calibrated are used, the minimum number of hammer blows
per unit of pile penetration needed to obtain the specified bearing value
of piles shall be determined by load tests, as provided in Subsections
400.1.2 and 400.1.3. In the absence of load tests, the safe bearing value
of each timber pile shall be determined by whichever of the following
approximate formulas is applicable:
1000 WH
For gravity hammer, P = ------------- x ---------------
6 S+25.4
For single-action steam or air hammers, and for diesel hammers having unrestricted rebound of ram,
1000 WH
P = ----------- x -----------------
6 S+2.54
For double-action steam or air hammers, and diesel hammers having enclosed ram,
1000 E
P = ------------ x -----------------
6 S+2.54
For diesel or steam hammers on very heavy piles,
1000 E
P = ---------- x ------------------------
6 S+2.54 (Wp/W)
Where:
- P = Safe load per pile in Newton or kg
- W = Weight of the striking part of the hammer in Newton or kg
- H = Height of fall of ram in meters
- S = Average penetration per blow in mm for the last5 to 10 blows for gravity hammers and the last10 to 20 blows for steam hammers
- E = Hammer energy, N.m or kg.m
- Wp = Weight of pile
The above formula are applicable only when:
- The hammer has a free fall.
- The head of the pile is free from broomed or crushed wood fiber or other serious impairment.
- The penetration is reasonably quick and uniform.
- There is no measurable bounce after the blow.
- A follower is not used.
If there is a measurable bounce, twice the height of bounce shall be
deducted from H to determine its value in the formula.
The bearing power as determined by the appropriate formula listed in this
Subsection, will be considered effective only when it is less than the
crushing strength of the pile. Other recognized formulas may be used if
fully detailed in the Special Provisions.
When bearing power is determined by a formula, timber piles shall be driven
until a computed safe bearing power of each is not less than 18 tonnes.
400.1.5 Concrete and Steel Pile Bearing Values
The bearing values for concrete and steel pile will be determined by the
Engineer using the following formulas:
a. Modified Hiley’s Formula or any formula from brochures of the equipment
used, shall be used when the ratio of weight of ram or hammer to weight of
pile is greater than one fourth (1/4).
2WH(W)
Ru = ----------------------------
(S+K) (W+Wp)
Ru
Ra = ---------------
FS
Where:
- Ru = ultimate capacity of piles (KN)
- Ra = capacity of pile (KN)–shall be greater than the required
- W = weight of ram or hammer (KN)
- H = height of fall of ram (mm)
- Wp = weight of pile (KN)
- S = average penetration for the last ten blows (mm)
- K = 10 mm (unless otherwise observed/computed during driving)
- FS = factor of safety (min. = 3)
b. Hiley’s Formula shall be used when the ratio of the weight of ramor
hammer to weight of pile is less than one fourth (1/4).
efWH (W) (W + n2Wp)
Ru = ------------------------------ x ---------------------------
S+1/2 (C1+C2+C3) (W + Wp)
Ru
Ra = --------------
FS
Where:
- Ru = ultimate capacity of pile (KN)
- Ra = capacity of pile (KN)
- Ef = efficiency of hammer (refer to table)
- W = weight of ram (KN)
- Wp = weight of pile (KN)
- H = height of fall of ram (mm)
- S = average penetration for last ten blows (mm)
- C1 = temporary compression allowance for pile head and cap (refer to table)
- C2 = RuL/AEp
- C3 = = range from 2.54 mm to 5.08 mm for resilient soil to 0 for hard pan (rock, very dense sand and gravel) length of pile
- L = length of pile
- A = cross-sectional area of pile
- Ep = modulus of elasticity of pile
- n = coefficient of restitution (refer to table)
- FS = factor of safety (min. = 3)
Required minimum penetration of all piles shall be six (6) meters. However,
for exposed piles, the embedded length shall be equal or greater than the
exposed length but not less than 6.0m.
Note:
Formula for other pile hammers with suggested factor of safety should be as
provided/recommended by their respective manufacturer.
Values of C1 for Hiley Formula
Temporary Compression Allowance C1 for Pile Head and Cap
Materials to which blow is applied
|
Easy Driving:
P1 = 3.45 MPa on Pile Butt If no cushion, mm
|
Medium Driving:
P1 = 6.90 MPa on Head or Cap.mm
|
Hard Driving:
P1 = 10.34 MPa on Head or Cap.mm
|
Very Hard Driving:
P1 = 13.88 MPa on Head or Cap.mm
|
| Head of timber pile
76–100mm packing inside capon head of precast concrete piles Concrete Pile Steel-covered cap. containing wood packing but steel piling at pipe 4.76mm red electrical tuber disk between two10mm steel plates, for use with severe driving on Monotube pile Head of steel piling of pipe |
1.27
27 + 1.778b
0.635
1.016
0.508
0
|
2.54
2.54 + 3.81b
1.27
2.032
1.016
0
|
3.81
3.81 + 5.588b
1.905
3.048
1.524
0
|
5.08
5.08 + 7.62b
2.54
4.064
2.032
0
|
b
The first figure represent the compression of the cap and wood dolly or
packing above the cap, whereas the second figure represent the compression
of the wood packing between the cap and the pile head.
P1 = Ru/A
Values of Efficiency of Hammer, ef
Hammer Type
|
ef
|
| Drop Hammer released by trigger
Drop Hammer actuated by rope and friction winch McKiernan-Terry Single-acting hammers Warrington-Vulcan Single –acting hammers Differential-acting hammers McKiernan-Terry, Industrial B. Ownhoist, National and Union double-acting hammers Diesel Hammers |
1.00
0.75 0.85 0.75 0.75 0.85 1.00 |
Values of Coefficient of Restitution, n
|
|||
| Pile Type
Reinforced Concrete Steel Timber |
Head Condition
Helmet with composite plastic or green heart dolly on top of pile Helmet with Timber dolly, and packing on top of pile Hammer direct on pile with pad only Driving cap with Standard plastic or greenheart dolly Driving cap with Timber dolly Hammer direct on pile Hammer direct on pile |
Drop, Single Acting or Diesel Hammer
0.40 0.25 - 0.50 0.30 - 0.25 |
Double Acting Hammers
0.50 0.40 0.50 0.50 0.30 0.50 0.40 |
The formulas specified in the preceding Subsection for timber piling may be
used in determining a rough approximation for the bearing power of precast
and cast-in-place concrete piles and of steel piles.
In all cases when the bearing power of concrete and steel piles is
determined by formula, the piles shall be driven until the safe bearing
power of each is computed to be not less than 27 tonnes.
400.1.6 Safe Loads
When the safe bearing power of any pile is found by test or computation to
be less than the design load, longer piles or additional piles shall be
driven as ordered in writing by the Engineer.
400.1.7 Jetted Piles
The safe bearing power of jetted piles shall be determined by actual tests
or by the appropriate methods and formulas given in the preceding
Subsections. No jet shall be used during the test blows.
400.2 Material Requirements
The kind and type of piles shall be as specified on the Plans and Bill of
Quantities. No alternative type or kind of piling shall be used.
400.2.1 Untreated Timber Piles
Timber shall conform to the requirements of Item 713, Treated and Untreated
Timber. The specie shall be specified on the Plans. Unless otherwise noted
on the Plans or Special Provisions, only the best grade shall be used. It
shall be free from loose knots, splits, wormholes, decay, warp, ring
separation or any defect which will impair its strength or render it unfit
for its intended use. Any specie specified on the Plans may be used for
untreated timber and if the specie is not available, a specie of equivalent
strength and durability may be used if authorized by the Engineer.
Round piles shall be cut above the ground swell and shall taper from butt
to tip. A line drawn from the center of the tip to the center of the butt
shall not fall outside of the cross-section of the pile at any point more
than one percent of the length of the pile.
In short bends, the distance from the center of the pile to a line
stretched from the center of the pile above the bend to the center of the
pile below the bend shall not exceed four percent of the length of the bend
or a maximum of 65mm.
Unless otherwise specified, all piles shall be peeled removing all rough
bark and at least 80 percent of the inner bark. Not less than 80 percent of
the surface on any circumference shall be clean wood. No strip of inner
bark remaining on the pile shall be more than 20mm wide and 200mm long. All
knots shall be trimmed close to the body of the pile.
The pile sizes shall conform to the dimensions shown in Table 400.1.
Table 400.1 – Dimension of Piles
Length of Pile
|
Diameter (1 meter from the Butt)
|
Minimum Tip Diameter, mm
|
|
Minimum mm
|
Maximum mm
|
||
| Less than 12 meters
12 to 18 meters More than 18 meters |
300
320
350
|
450
450
500
|
200
180
150
|
The diameter of the piles shall be measured in their peeled condition. When
the pile is not exactly round, the average of three measurements may be
used. For any structure, the butt diameters for the same lengths of pile
shall be as uniform as possible.
Square piles shall have the dimensions shown on the Plans.
400.2.2 Treated Timber Piles
Timber shall conform to the requirements of Item 713, Treated and Untreated
Timber. Treatment shall consist of the forcing of either creosote oil or
creosote petroleum oil mixture into the outer fibers of the timber by a
heat and pressure process. The process shall be in accordance with ASTM
D-1760Standard Specification for Pressure Treatment of Timber Products, but
with such changes as temperatures, pressures, duration of treatment and
other factors affecting the final treatment that experience has shown to be
necessary in the treatment of structural timbers sawn from woods native to
the Philippines. The treatment shall be so regulated that the curing
process will not induce excessive checking. The minimum penetration of the
preservative into the surface of the timber shall be 20 mm. All piles shall
retain the minimum amount of preservative specified in Table 400.2.
Table 400.2 – Minimum Preservative Per Cubic Meter of Wood
Use
|
Type of Processing
|
|
Empty Cell Process
|
Full Cell Process
|
|
General Use
Marine Use
|
195 kg
|
320 kg
|
The Engineer shall inspect the timber prior to the treatment to determine
conformance with the Specifications and suitability of conditions for
treatment. He shall be permitted free access to the plant in order that
temperatures, pressures and quantities and type of treatment materials used
may be observed. Samples of the creosote or creosote petroleum mixtures
shall be furnished as required for test.
The timber shall be checked to determine penetration of treatment, quantity
of free preservative remaining on the timber and any visual evidence that
the treatment has been performed in a satisfactory manner. The penetration
of treatment shall be determined by boring a sufficient number of
well-distributed holes to determine the average penetration. All such holes
shall be plugged with plugs approximately 2 mm larger in diameter than the
bit used in boring the holes.
If the penetration of preservative is less than the required amount, the
entire charge, or such parts thereof shall be retreated. If after treatment
the penetration is still insufficient, the treated pieces shall be
rejected.
400.2.3 Concrete Piles
Concrete shall conform to the requirements of Item 405, Structural
Concrete. Concrete shall be Class “C” unless otherwise specified in the
Plans.
Concrete shall be proportioned to achieve a range of 6”-8” (150 mm to
200mm) slump, self-compacting mix, or as directed by the Engineer.
The use of appropriate plasticizer/additives to assure mix fluidity and
consistency shall be allowed and with the Engineer’s approval. A retardant
of proven adequacy and approved by the Engineer may be used to ensure that
early hardening of concrete during operation will not occur.
Reinforcing steel shall conform to the requirements of Item 404,
Reinforcing Steel. Prestressing reinforcing steel shall be high-tensile
steel wire conforming to AASHTO M 204 or other high-tensile metals
conforming to AASHTO Standards.
400.2.4 Steel Shells
1. Shells Driven Without a Mandrel
Unless otherwise called for on the Plans or Special Provisions, shells for
cast-in-place concrete piles shall have a minimum 305mm diameter at cut off
and a minimum 203mm diameter at tip: made from not less than 4.55mm in
thickness plate stock conforming to AASHTO M 183. Shells may either be
spirally welded or longitudinally welded and may either be tapered or
constant in section. Tips shall be sealed as shown on the Plans.
2. Shells Driven With a Mandrel
The shell shall be of sufficient strength and thickness to withstand
driving without injury and to resist harmful distortion and/or buckling due
to soil pressure after driven and the mandrel removed. Butt and tip
dimension shall be as called for on the Plans or Special Provisions.
400.2.5 Steel Pipes
Filled Steel Pipes (filled with concrete) shall conform to the requirements
of ASTM A 252, Grade 2, Welded and Seamless Pipe Piles. Closure Plates for
closed piles shall conform to the requirements of AASHTO M 183.
Unfilled Tubular Steel Piles shall conform to the requirements of ASTM
A252, Grade 2, with chemical requirements meeting ASTM Designation A 53,
Grade B. The wall thickness shall not be less than 4.76mm.
400.2.6 Steel H-Piles
Steel H-Piles shall be rolled steel sections of the weight and shape called
for on the Plans. They shall be structural steel meeting the requirements
of AASHTO M 183 provided that, where the Special Provisions called for
copper-bearing structural steel, the steel shall not contain less than
one-fifth percent nor more than zero point thirty five percent (0.35%) of
copper, except that steel manufactured by the acid-bessemer process shall
not be used.
400.2.7 Sheet Piles
Steel sheet piles shall meet the requirements of AASHTO M 202 (ASTM A328),
or AASHTO M 223. All other sheet piles shall meet the requirements
prescribed above the particular material specified. The joints shall be
practically water-tight when the piles are in place.
400.2.8 Pile Shoes
Pile shoes shall be as called for on the Plans.
400.2.9 Splices
Material for pile splices, when splicing is allowed, shall be of the same
quality as the material used for the pile itself and shall follow the
requirements given on the Plans.
400.2.10 Paint
It shall conform to Item 709, Paints.
400.3 Construction Requirements
400.3.1 Location and Site Preparation
Piles shall be driven where indicated on the Plans or as directed by the
Engineer.
All excavations for the foundation on which the piles are to be driven
shall be completed before the pile driving, unless otherwise specified or
approved by the Engineer. After driving is completed, all loose and
displaced materials shall be removed from around the piles by hand
excavation, leaving clean solid surface to receive the concrete of the
foundation. Any requirement for granular fill and lean concrete shall be
indicated on the Plans or as directed by the Engineer.
400.3.2 Determination of Pile Length
Pile length and bearing capacity shall be determined by the Engineer from
the results of the test piling and load tests.
The criterion for pile length may be one of the following:
1. Piles in sand and gravel shall be driven to a bearing power determined
by the use of the pile driving formula or as decided by the Engineer.
2. Piles in clay shall be driven to the depth ordered by the Engineer.
However, the bearing power shall be controlled by the pile driving formula
if called for by the Engineer.
3. Piles shall be driven to refusal on rock or hard layer when so ordered
by the Engineer.
The Contractor shall be responsible for obtaining the correct pile length
and bearing capacity according to the criteria given by the Engineer.
400.3.3 Pile Driving
All piles shall be driven as shown on the Plans or as ordered in writing by
the Engineer. They shall be driven within an allowed variation of 20 mm per
meter of pile length from the vertical or batter as shown on the Plans. The
maximum allowable variation at the butt end of the pile shall be 75 mm in
any direction from the location shown on the Plans or as directed by the
Engineer. Each pile shall, after driving, be within 150mm from the
theoretical location underneath the pile cap or underneath the
superstructure in case of pile bents. All piles pushed up by the driving of
adjacent piles or any other cause shall be redriven.
Piles shall be used only in places where the minimum penetration of 3 m
infirm materials, or 5 m in soft materials can be obtained. Whereas soft
upper stratum overlies a hard stratum, the piles shall penetrate the hard
materials at sufficient depths to fix the ends rigidly.
All pile driving equipment is subject to the Engineer’s approval. The
Contractor is responsible for sufficient weight and efficiency of the
hammers to drive the piles down to the required depth and bearing capacity.
Hammers shall be gravity hammers, single and double acting steam or
pneumatic hammers or diesel hammers. Gravity hammers shall not weigh less
than 60 percent of the combined weight of the pile and driving head but not
less than 2,000 kg. The fall shall be regulated so as to avoid injury to
the pile and shall in no case exceed4.50m for timber and steel piles and
2.50m for concrete piles unless otherwise specified or approved by the
Engineer.
The plant and equipment furnished for steam hammers shall have sufficient
capacity to maintain, under working condition, the pressure at the hammer
specified by the manufacturer. The boiler or pressure tank shall be
equipped with an accurate pressure gauge and another gauge shall be
supplied at the hammer intake to determine the drop in pressure between the
gauges. When diesel hammers or any other types requiring calibration are
used, they shall be calibrated with test piling and/or test loads in
accordance with Subsection 400.1.2, Test Piles.
Water jets shall be used only when permitted in writing by the Engineer.
When water jets are used, the number of jets and the nozzle volume and
pressure shall be sufficient to erode freely the material adjacent to the
pile. The plant shall have sufficient capacity to deliver at all time a
pressure equivalent to at least 690 KPa at two 19 mm jet nozzles. The jets
shall be shut off before the required penetration is reached and the piles
shall be driven solely by hammers to final penetration as required by the
Engineer.
Piles shall be supported in line and position with leads while being
driven. Pile driving leads shall be constructed in such a manner as to
afford freedom of movement of the hammer, and shall be held in position by
guys or steel braces to insure rigid lateral support to the pile during
driving. The leads shall be of sufficient length to make the use of a
follower unnecessary and shall be so designed as to permit proper placing
of batter piles. The driving of the piles with followers shall be avoided
if practicable and shall be done only under written permission from the
Engineer.
The method used in driving piles shall not subject them to excessive and
undue abuse producing crushing and spalling of the concrete, injurious
splitting, splintering and brooming of the wood or deformation of the
steel. Manipulation of piles to force them into proper position if
considered by the Engineer too excessive will not be permitted.
The pile tops shall be protected by driving heads, caps or cushions in
accordance with the recommendation of the manufacturer of the pile hammer
and to the satisfaction of the Engineer. The driving head shall be provided
to maintain the axis of the pile with the axis of the hammer and provide a
driving surface normal to the pile.
Full length piles shall be used where practicable. Splicing of piles when
permitted, shall be in accordance with the provisions of Subsection 400.3.7
and400.3.8. All piles shall be continuously driven unless otherwise allowed
by the Engineer.
Piles shall not be driven within 7 m of concrete less than 7 days old.
400.3.4 Timber Piles
Piles shall be strapped with three metal straps: one about 450mm from the
butt, one about 600mm from the butt, and the third, about 300mm from the
tip. Additional straps shall be provided at about 4.5m on centers between
tip and butt. Strapping should encircle the pile once and be tensioned as
tightly as possible. Straps shall be 38mm wide, 0.8mm thick, cold rolled,
fully heat treated, high tensile strapping, painted and waxed.
Treated piles shall be strapped after treatment.
Point protection shall be considered for all timber piles. Where timber
piles must penetrate dump fill, or may encounter obstructions or be driven
to hard strata, point protection shall be used. A boot that encompasses and
utilizes the entire end area of the pile is preferred.
400.3.5 Timber Pile Bents
Piles for any one bent shall be carefully selected as to size, to avoid
undue bending or distortion of the sway bracing. Care shall be exercised in
the distribution of piles of various sizes to obtain uniform strength and
rigidity in the bents of any given structure.
Cut offs shall be made accurately to insure full being between caps and
piles of bents.
400.3.6 Precast Concrete Piles
Precast concrete piles shall be of the design shown on the Plans.
Prestressed concrete piles shall be prestressed as prescribed in Item 406,
Prestressed Concrete Structures. The piles shall be cast separately and
concrete in each pile shall be place continuously. The completed piles
shall be free from stone pockets, honeycombs, or other defects, and shall
be straight and true to the form specified. The forms shall be true to line
and built of metal, plywood or dressed lumber. A 25 mm chamfer strip shall
be used in all corners. Form shall be water-tight and shall not be removed
until at least twenty-four (24) hours after the concrete is placed.
Piles shall be cured and finished in accordance with Items 405, Structural
Concrete and 406, Prestressed Concrete Structures.
Cylinder specimens shall be made and tested in accordance with Item
405.Piles shall not be moved until the tests indicate that the concrete has
attained a compressive strength of at least 80 percent (80%) of the design
28-daycompressive strength and they shall not be transported or driven
until the design28-day compressive strength has been attained.
If testing equipment is not available, as in isolated areas, piles shall
not be moved until after fourteen (14) days after casting and shall not be
transported or driven prior to 28 days after casting. If high early
strength cement is used, piles shall not be moved, transported or driven
prior to 7 days after casting.
When concrete piles are lifted or moved, they shall be supported at the
points shown on the Plans; if not shown, they shall be supported at the
quarter points.
400.3.7 Cast-in-place Concrete Piles
1. Drilled Holes
All holes for concrete piles cast in drilled holes shall be drilled dry to
tip elevation shown on the Plans. All holes will be examined for
straightness and any hole which on visual inspection from the top shows
less than one-half the diameter of the hole at the bottom of the hole will
be rejected. Suitable casings shall be furnished and placed when required
to prevent caving of the hole before concrete is placed.
All loose material existing at the bottom of the hole after drilling
operations have been completed shall be removed before placing concrete.
The use of water for drilling operations or for any other purpose where it
may enter the hole will not be permitted. All necessary action shall be
taken to prevent surface water from entering the hole and all water which
may have infiltrated into the hole shall be removed before placing
concrete.
Concrete shall be placed by means of suitable tubes. Prior to the initial
concrete set, the top 3m of the concrete filled pile or the depth of any
reinforcing cage, whichever is greater, shall be consolidated by acceptable
vibratory equipment,
Casing, if used in drilling operations, may be left in place or removed
from the hole as concrete is placed. The bottom of the casing shall be
maintained not more than 1.5 m nor less than 0.3 m below the top of the
concrete during withdrawal and placing operations unless otherwise
permitted by the Engineer. Separation of the concrete during withdrawal
operations shall be avoided by vibrating the casing.
2. Steel Shells and Pipes
The inside of shells and pipes shall be cleaned and all loose materials
removed before concrete is placed. The concrete shall be placed in one
continuous operation from tip to cut-off elevation and shall be carried on
in such a manner as to avoid segregation.
The top 3 m of concrete filled shells, or to the depth of any reinforcing
cage, whichever is greater, shall be consolidated by acceptable vibratory
equipment.
Pipes shall be of the diameter shown on the Plans. The pipe wall thickness
shall not be less than that shown on the Plans but in no case less than
5mm. The pipe, including end closures, shall be of sufficient strength to
be driven by the specified methods without distortion.
Closure plates and connecting welds shall not project more than 12.5 mm
beyond the perimeter of the pile tips.
No shell or pipe shall be filled with concrete until all adjacent shells,
pipes, or piles within a radius of 1.5 m or 4 ½ times the average pile
diameter, whichever is greater, have been driven to the required
resistance.
After a shell or pipe has been filled with concrete, no shell, pipe or pile
shall be driven within 6m thereof until at least 7 days have elapsed.
3. Drilled Shafts
Drilled shafts are deep foundations formed by boring a cylindrical hole
into soil and/or rock and filling the hole with concrete. Drilled shafts
are also commonly referred to as caissons, bored piles or drilled piers.
Drilled shafts, like driven piles, transfer structural loads to bearing
stratum well below the base of the structure by passing soils having
insufficient strength to carry the design loads.
Drilled shafts are classified according to their primary mechanism for
deriving load resistance either as floating shafts (i.e., shafts
transferring load primarily by side resistance), or end-bearing shafts
(i.e., shafts transferring load primarily by tip resistance). Occasionally,
the bases of shafts are enlarged (i.e., belled or underreamed) to improve
the load capacity of end bearing shafts on less than desirable soils, or to
increase the uplift resistance of floating shafts.
Effects of ground and ground water conditions on shaft construction
operations should be considered and delineated, when necessary, the general
method of construction to be followed to ensure the expected performance.
Because shafts derive their capacity from side and tip resistance which are
a function of the condition of the materials in direct contact with the
shaft, it is important that the construction procedures be consistent with
the material conditions assumed in the design. Softening, loosening or
other changes in soil and rock conditions caused by the construction method
could result in a reduction in shaft capacity and an increase in shaft
displacement. Therefore, evaluation of the effects of shaft construction
procedure on load capacity must be considered an inherent aspect of the
design.
Drilled shafts are normally sized in 15.24 cm diameter increments with a
minimum diameter of 45.72 cm. The diameter of a shaft socketed into rock
should be a minimum of 15.24 cm larger than the socket diameter. If a shaft
must be inspected by the entry of a person, the shaft diameter shall not be
less than 76.20 cm.
Drilled shafts constructed in dry, noncaving soils can usually be excavated
without lateral support of the hole. Other ground conditions where caving,
squeezing or sloughing soils are present require installation of a steel
casing or use of a slurry for support of the hole. Such conditions and
techniques may result in loosening of soil around the shaft, or altering of
frictional resistance between the concrete shaft and surrounding soil.
The center-to-center spacing between shafts is normally restricted to a
minimum of 3B to minimize the effects of interaction between adjacent
shafts during construction or in service. However, larger spacings may be
required where drilling operations are difficult or where construction must
be completed in very short time frames.
Particular attention should be given to the potential for deposition of
loose or wet material in the bottom of the hole, or the buildup of a cake
of soft material around the shaft perimeter prior to concrete placement.
Adequate cleaning and inspection of rock sockets should always be performed
to assure good contact between the rock and shaft concrete. If good contact
along the shaft cannot be confirmed, it may be necessary to assume that all
load is transferred to the tip. If the deposition of soft or loose material
in the bottom of the hole is expected, the shaft may have to be designed to
carry the entire design load through side resistance.
A number of methods can be used to prevent caving during the drilling of
holes and the placement of concrete. It is preferred that drilled shafts be
constructed in stable non-sloughing soil without excessive ground water. If
impossible, consider the following three different construction methods:
a. The construction of the pile or shaft in a wet condition while the walls
of the excavation are stabilized by hydrostatic pressure of water or a
mineral slurry until the concrete is placed by tremie methods for the full
length of the pile.
Mineral slurry used in the drilling process shall have both a mineral grain
size that will remain in suspension and sufficient viscosity and gel
characteristics to transport excavated material to a suitable screening
system. The percentage and specific gravity of the material used to make
the suspension shall be sufficient to maintain the stability of the
excavation and to allow proper concrete placement. The level of the slurry
shall be maintained at a height sufficient to prevent caving of the hole.
The mineral slurry shall be premixed thoroughly with clean fresh water and
adequate time allotted for hydration prior to introduction into the shaft
excavation. Adequate slurry tanks will be required when specified. No
excavated slurry pits will be allowed when slurry tanks are required on the
project without written permission of the Engineer. Adequate desanding
equipment will be required when specified. Steps shall be taken as
necessary to prevent the slurry from “setting up” in the shaft excavation,
such as agitation, circulation, and adjusting the properties of the slurry.
Control tests using suitable apparatus shall be carried out by the
Contractor on the mineral slurry to determine density, viscosity, and pH.
An acceptable range of values for those physical properties is shown in the
following table.
Range of Values (At 200C)
Property (Units)
|
Time of Slurry Introduction
|
Time of Concreting (In Hole)
|
Test Method
|
| Density (KN/m3)
Viscosity (sec. per liter) pH |
10.10 to 10.86
28 to 45 8 to 11 |
10.10 to 11.79
28 to 45 8 to 11 |
Density Balance
Marsh Cone pH Paper or Meter |
Note:
a) Increase density values by 0.314 (KN/m3) in salt water.
b) If desanding is required; sand content shall not exceed 4 percent (by
volume) at any point in the shaft excavation as determined by the American
Petroleum Institute sand content test.
Tests to determine density, viscosity and pH values shall be done during
the shaft excavation to establish a consistent working pattern.
Prior to placing shaft concrete, slurry samples shall be taken from the
bottom and at intervals not exceeding 3.05 m for the full height of slurry.
Any heavily contaminated slurry that has accumulated at the bottom of the
shaft shall be eliminated. The mineral slurry shall be within specification
requirements immediately before shaft concrete placement.
Excavation Inspection
The Contractor shall provide equipment for checking the dimensions and
alignment of each shaft excavation. The Contractor under the direction of
the Engineer shall determine the dimensions and alignment of the drilled
shaft. Final shaft depth shall be measured after final cleaning.
The base of the shaft excavation may be cleaned using a cleaning bucket
followed by airlifting. Reverse circulation techniques may also be used to
clean the base of the shaft.
The shaft excavation shall be cleaned so that a minimum of 50 percent of
the base will have less than 12.5 mm of sediment and at no place on the
base more than 37.5 mm of sediment. The Engineer will determine shaft
cleanliness.
b. The use of steel casing which is installed during drilling operations
tohold the hole open and usually withdrawn during concrete placement.
Casing, if used in operation, shall be metal, smooth, clean, watertight,
and of ample strength to withstand both handling and driving stresses and
the pressure of both concrete and the surrounding earth materials. The
outside diameter of casing shall not be less than the specified size of the
shaft. It shall conform to AASHTO M 270 (ASTM A 709) Grade 36 unless
otherwise specified.
Temporary casings shall be removed while the concrete remains workable.
Generally the removal of temporary casing shall not be started until
concrete placement in the shaft is at or above ground surface. Movement of
casing by rotating, exerting downward pressure and tapping to facilitate
extraction or extraction with a vibratory hammer will be permitted. Casing
extraction shall be at a slow, uniform rate with the pull in line with the
shaft axis.
A sufficient head of concrete shall be maintained above the bottom of the
casing to overcome the hydrostatic pressure of water or drilling fluid
outside of the casing.
c. The use of a permanent casing which is left in place within the portion
of the pile which is in unstable material.
A permanent casing is applied as protection from the presence of surface
water during drilling and as support later for the installation of the
rebar cage and as a concrete form in drilling under water.
Reinforcing Steel Cage Construction and Placement
The reinforcing steel cage consisting of the steel shown on the Plans plus
cage stiffener bars, spacers, centralizers and any other necessary
appurtenances shall be completely assembled and placed as a unit
immediately after the shaft excavation is inspected and accepted and prior
to shaft concrete placement.
Where the reinforcing cage length is too long for placement as a single
unit the cage may be placed in separate units such that appropriate means
of splicing the longitudinal steel is provided for. The Contractor shall
submit his plans for such splices to the Engineer for approval.
The reinforcing steel in the hole shall be tied and supported so that the
reinforcing steel will remain within allowable tolerances until the
concrete will support the reinforcing steel. When concrete is placed by
suitable tubes, temporary hold-down devices shall be used to prevent
uplifting of the steel cage during concrete placement. Concrete spacers or
other approved noncorrosive spacing devices shall be used at sufficient
intervals not exceeding 1.50 meters along the shaft to insure concentric
location of the cage within the shaft excavation. When the size of the
longitudinal reinforcing steel exceeds 25 mm, such spacing shall not exceed
3.0 meters.
Concrete Placement, Curing and Protection
Concrete shall be placed as soon as possible after reinforcing steel cage
placement. Concrete placement shall be continuous in the shaft to the top
elevation of the shaft. Placement shall continue after the shaft is full
until good quality concrete is evident at the top of the shaft. Concrete
shall be placed through a suitable tube.
For piles less than 2.5 meters in diameter, the elapsed time from the
beginning of concrete placement in the shaft to the completion of placement
shall not exceed 2 hours. For piles 2.50 meters and greater in diameter,
the concrete placing rate shall not be less than 9.0 meters of pile height
per each 2-hourperiod. The concrete mix shall be of such design that the
concrete remains in a workable plastic state throughout the 2-hour
placement limit.
When the top of pile elevation is above ground, the portion of the pile
above ground shall be formed with a removable form or permanent casing when
specified.
The upper 1.5 meters of concrete shall be vibrated or rodded to a depth of
1.5 meter below the ground surface except where soft uncased soil or slurry
remaining in the excavation will possibly mix with the concrete.
After placement, the temporarily exposed surfaces of the shaft concrete
shall be cured in accordance with the provision in Sub-section 407.3.8 –
Curing Concrete.
For at least 48 hours after pile concrete has been placed, no construction
operations that would cause soil movement adjacent to the shaft, other than
mild vibration, shall be conducted.
Construction Tolerances:
The following tolerances shall be maintained in constructing drilled shaft:
a. The drilled shaft shall be within 15.24 cm of the plan position in the
horizontal plane at the plan elevation for the top of the shaft.
b. The vertical alignment of the shaft excavation shall not vary from the
plan alignment by more than 20.83 mm/m of depth.
c. After all the shaft concrete is placed, the top of the reinforcing steel
cage shall be no more than 15.24 cm above and no more than 7.62cm below
plan position.
d. When casing is used, its outside diameter shall not be less than the
shaft diameter shown on the plans. When casing is not used, the minimum
diameter of the drilled shaft shall be the diameter shown on the plans for
diameters 60.96 cm or less, and not more than 2.54 cm less than the
diameter shown on the plans for diameters greater than 60.96 cm.
e. The bearing area of bells shall be excavated to the plan bearing area as
a minimum. All other plan dimensions shown for the bells may be varied,
when approved, to accommodate the equipment used.
f. The top elevation of the shaft shall be within 2.54 cm of the plan top
of shaft elevation.
g. The bottom of the shaft excavation shall be normal to the axis of the
shaft within 62.5 mm/m of shaft diameter.
Drilled shaft excavations constructed in such a manner that the concrete
shaft cannot be completed within the required tolerances are unacceptable.
400.3.8 Steel H-Pile
Steel H-Pile shall consist of structural steel shapes of the sections
indicated on the Plans.
When placed in the leads, the pile shall not exceed the camber and sweep
permitted by allowable mill tolerance. Piles bent or otherwise damaged will
be rejected.
The loading, transporting, unloading, storing and handling of steel H-pile
shall be conducted so that the metal will be kept clean and free from
damage.
400.3.9 Unfilled Tubular Steel Piles
The tubular steel piles should be or as specified by the Engineer.
The minimum wall thickness shall be as indicated in the following table:
Outside Diameter
|
Less than 355 mm | 355 mm and over |
| Minimum wall thickness |
6.5 mm
|
9.5 mm
|
Cutting shoes for piles driven open end may be inside or outside of the
pipe. They may be high carbon structural steel with a machined ledged for
pile bearing or cast steel with a ledge, designed for attachment with a
simple weld.
400.3.10 Splicing
Splicing when permitted shall be made as shown on the Plans and in
accordance with this Subsection.
1. Precast Concrete Piles
a. By using prefabricated joints mounted in the forms and cast together
with the piles sections and joined together as specified by the
manufacturer and approved by the Engineer. The joints shall be of the
design and type as specified or shown on the Plans.
b. By cutting away the concrete at the end of the pile, leaving the
reinforcing steel exposed for a length of 40 bar diameters for corrugated
or deformed bars and 60 bar diameters for plain bars. The final cut of the
concrete shall be perpendicular to the axis of the pile. Reinforcement of
the same size as that used in the pile shall be spliced to the projecting
steel in accordance with Item 404, Reinforcing Steel, and the necessary
formwork shall be placed, care being taken to prevent leakage along the
pile. The concrete shall be of the same quality as that used in the pile.
Just prior to placing concrete, the top of the pile shall be wetted
thoroughly and covered with a thin coating of neat cement, retempered
mortar, or other suitable bonding material to the satisfaction of the
Engineer. The forms shall remain in place not less than seven (7) days. The
pile shall not be driven until the safe design has been reached.
c. By any other method shown on the Plans or approved by the Engineer.
Curing and finishing of extensions shall be the same as in the original
pile.
2. Prestressed Piles
Splicing of prestressed precast piles will generally not be permitted, but
when permitted, it shall be made in accordance with (1) above, but only
after driving has been completed. Reinforcement bars shall be included in
the pile head for splicing to the extension bars. No additional driving
will be permitted. The Contractor, at his option, may submit alternative
plans of splicing for consideration by the Engineer.
3. Steel Piles, Shells or Pipes
If the length of the steel pile, shell or pipe driven is insufficient to
obtain the specified bearing power, an extension of the same cross-section
shall be spliced to it. Unless otherwise shown on the Plans, splices shall
be made by butt-welding the entire cross-sections to form an integral pile
using the electric arc method. The sections connected shall be properly
aligned so that the axis of the pile shall be straight. Bent and/or damaged
piles shall be rejected.
400.3.11 Cutting Off and Capping Piles
The top of foundation piles shall be embedded in the concrete footing as
shown on the Plans.
Concrete piles shall, when approved by the Engineer, be cut off at such a
level that at least 300mm of undamaged pile can be embedded in the
structure above. If a pile is damaged below this level, the Contractor
shall repair the pile to the satisfaction of the Engineer. The longitudinal
reinforcement of the piles shall be embedded in the structure above to a
length equal to at least 40 times the diameter of the main reinforcing
corrugated bars (60 diameters for plain bars).The distance from the side of
any pile to the nearest edge of the cap shall not be less than 200 mm.
When the cut off elevation for a precast pile or for the steel shell or
pile fora cast in place concrete pile is below the elevation of the bottom
of the pile cap, the pile may be built-up from the butt of the pile to the
elevation of the bottom of the cap by means of reinforced concrete
extension constructed in accordance with Subsection 400.3.10 or as approved
by the Engineer.
Cut-offs of structural steel piles shall be made at right angles to the
axis of the pile. The cuts shall be made in clear, straight lines and any
irregularity due to cutting or burning shall be leveled-off with deposits
of weld metal prior to placing bearing caps.
400.3.12 Defective Piles
Any pile delivered with defects, or damaged in driving due to internal
defects or by improper driving, or driven out of its proper location, or
driven below the elevation fixed by the Plans or by the Engineer, shall be
corrected at the Contractor’s expense by one of the following methods
approved by the Engineer for the pile in question:
1. Any pile delivered with defects shall be replaced by a new pile.
2. Additional pile shall be driven/casted at the location as directed by
the Engineer.
3. The pile shall be spliced or built-up as otherwise provided herein on
the underside of the footing lowered to properly embed the pile.
A precast concrete pile shall be considered defective if it has a visible
crack, extending around the four sides of the pile, or any defect which, in
the opinion of the Engineer, affects the strength or life of the pile.
When a new pile is driven or cast to replace a rejected one, the Contractor
at his own expense, shall enlarge the footing as deemed necessary by the
Engineer.
400.3.13 Protecting Untreated Timber Trestle Piles
The heads of untreated piles shall be treated as follows:
The sawed surface shall be thoroughly brush-coated with two (2)
applications of hot creosote oil or other approved preservative.
400.3.14 Protecting Treated Timber Trestle Piles
All cuts and abrasions in treated timber piles shall be protected by a
preservative approved by the Engineer.
400.3.15 Painting Steel Piles
Unless otherwise provided, when required steel piles extend above the
ground surface or water surface, they shall be protected by paint as
specified for cleaning and painting metal surfaces in accordance with Item
403, Metal Structures. This protection shall extend from the elevation
shown on the Plans to the top of the exposed steel.
400.3.16 Pile Records
The Contractor shall keep records of all piles driven or installed. A copy
of the record shall be given to the Engineer within two (2) days after each
pile is driven. The record form to be used shall be approved by the
Engineer. The pile records shall give full information on the following:
Driven Piles
|
Cast-in-Place Piles
|
| 1. Pile type and dimension
2. Date of casting and concrete quality (for concrete piles) 3. Date of driving 4. Driving equipment: type, weight & efficiency of hammer, etc. 5. Description of cushion on pile head 6. Depth driven and tip elevation 7. Final set for the last 20 blows (for every 10 piles and when the Engineer so requires the penetration along the whole depth driven shall be recorded) 8. For gravity and single-acting hammers: the height of drop 9. For double acting-hammers-the frequency of blows 10. Details of any interruption in driving 11. Level of pile top immediately after driving and the level when all piles in the group are driven 12. Details of re-driving |
1. Date of boring or driving (For steel shell) &
casting
2. Pile type and nominal dimension 3. Length of finished pile and tip elevation 4. Details of penetration during boring or driving of steel shell(driving records as for driven piles) 5. Concrete quality and consistency 6. Time interval between boring or driving and concreting 7. Volume of concrete placed in concrete |
400.4 Method of Measurement
400.4.1 Timber, Steel and Precast Concrete Piles
1. Piles Furnished
The quantity to be paid for will be the sum of the lengths in meters of the
piles of the several types and lengths ordered in writing by the Engineer,
furnished in compliance with these Specifications and stockpiles in good
condition at the project site by the Contractor and accepted by the
Engineer. The length to be paid for will include test and tension piles
ordered by the Engineer, but not those furnished by the Contractor at his
option. No allowance will be made for piles, including test piles,
furnished by the Contractor to replace piles previously accepted by the
Engineer that are subsequently lost or damaged while in stockpile, or
during handling or driving, and are ordered by the Engineer to be removed
from the site of work.
In case extensions of piles are necessary, the extension length will be
included in the length of pile furnished, except for cut off lengths used
for extensions and already measured for payment.
2. Piles Driven
The quantity to be paid for will be the sum of the lengths in meters of the
piles driven in the completed work measured from the pile tip elevation to
the bottom of pile caps, footings or bottom of concrete superstructure in
the case of pile bents. Measurement will not include additional piles or
test piles driven that may be necessary to suit the Contractor’s method of
construction and were driven at his option.
Unless otherwise provided for, pre boring, jetting or other methods used
for facilitating pile driving operations will not be measured directly but
will be considered subsidiary to pay items.
400.4.2 Cast-In-Place Concrete Piles
The quantity to be paid for will be the sum of actual lengths in meters of
the piles cast and left in-place in the completed and accepted work.
Measurements will be from the pile tip to the bottom of cap or footing.
Portions of piles cast deeper than the required length through
over-drilling will not be measured for payment.
400.4.3 Pile Shoes
The quantity to be paid for, including test pile shoes, will be the number
of pile shoes driven shown on the Plans or ordered in writing by the
Engineer, furnished by the Contractor in accordance with these
Specifications and accepted by the Engineer. Pile shoes furnished by the
Contractor at his option or to replace those that are lost or damaged in
stockpile or handling will not be measured for payment.
400.4.4 Load Tests
The quantity of the load tests to be paid for will be the number of tests
completed and accepted except that load tests made to calibrate different
types of hammers, if not included in the Bill of Quantities, will not be
measured for payment.
Anchor and test piling which are not part of the completed structure, will
be included in the unit bid price for each “Load Test”. Anchor and test
piling or anchor and test shafts which are a part of the permanent
structure will be paid for under the appropriate Item.
400.4.5 Splices
The quantity to be paid for will be the number of splices which may be
required to drive the pile in excess of the estimated length shown on the
Plans for cast-in-place steel pipes or shells or in excess of the order
length furnished by the Engineer for all other types of piling. Splices
made for the convenience of the Contractor or to fabricate piles cut offs
will not be paid for.
400.5 Basis of Payment
The accepted quantities, measured as prescribed in Section 400.4 shall be
paid for at the contract unit price for each of the particular item listed
below that is included in the Bill of Quantities, which price and payment
shall be full compensation for furnishing and placing all materials,
including all labor, equipment tools and incidentals as well as temporary
works, staging areas or craneway necessary to complete the work prescribed
in this Item.
Payment will be made under:
Pay Item Number
|
Description
|
Unit of Measurement
|
400 (1)
400 (2)
400 (3)
400 (4)
400 (5)
400 (6)
400 (7)
400 (8)
400 (9)
400 (10)
400 (11)
400 (12)
400 (13)
400 (14)
400 (15)
400 (16)
400 (17)
400 (18)
400 (19)
400 (20)
400 (21)
400 (22)
400 (23)
400 (24)
|
Untreated Timber Piles, furnished
Treated Timber Piles, preservative, furnished Steel H-Piles, furnished Precast Concrete Piles, furnished Precast, Prestresssed Concrete Piles, furnished Structural Steel Sheet Piles, furnished Precast Concrete Sheet Piles, furnished Untreated Timber Piles, driven Treated Timber Piles, driven Steel H-Piles, driven Steel Pipes Piles Structural Steel Sheet Piles, driven Precast Concrete Sheet Piles, driven Precast Concrete Piles, driven Precast, Prestresssed Concrete Piles, driven Test Piles, furnished and driven Concrete Piles cast in Drilled Holes Concrete Piles cast in Steel Shells Concrete Piles cast in Steel Pipes Pile Shoes Splices Load Tests Bored Piles (dia. __m) Permanent Casing (dia. ___m) |
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Each
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