Page 31 - Building Regulation and Design Guidelines - Structural (Grey Code)

SECTION: 1 GEOTECHNICAL GUIDELINES & REGULATIONS SECTION: 1 GEOTECHNICAL GUIDELINES & REGULATIONS

d) Before Installing steal cage and casting concrete when reaching load. ASTM D 4945-89.
the pile toe level, loose and remolded material and debris will be
removed with the drilling or cleaning bucket. d) 10% of the total number of working piles shall be tested using cross-
hole sonic core logging test method for piles of diameter equal or
e) High slump concrete of specified grade should be used according to more than 600mm. ASTM D 6760-08.
Table 14 of BS 8004 : 1986
e) 100 % of working piles shall be tested by using low strain dynamic
f) For a continuous assurance of concrete quality and integrity, integrity test and shall be repeated for piles statically tested. ASTM
concrete should be poured to minimum 1.50 m above the theoretical D 5882-07.
pile cut-off level.
f) The following procedure shall be followed for particular tests
g) Casting of piles shall be performed as a continuous operation. The whenever are required by the project specification or design
concrete should be designed to remain workable for a minimum of conditions:
three hours from the time of the batching to the time of placement
into the pile. - Pile instrumentation test should be performed on tested pile(s).
The test shall be performed at the time of static load test for
h) The concrete shall be placed by tremie tube method; the tube piles of diameters 1000 mm or more.
diameter. shall not be less than 150 mm. The tube shall be inserted
at the centre of the pile to reach the toe. The top shall be connected - Static laterally loaded piles test should be conducted where the
to a funnel. The concrete shall be delivered directly from the transit lateral loads governing the design.
mixer to the funnel. The tube to be lifted 100 mm above pile toe - Static tension pile test should be conducted where tension
level prior to concreting. While concreting, the length of the tube to piles are used to resist uplift.
be shortened if necessary but shall be maintained always into the
concrete of at least 2.0 m length. - 10 % of working piles boreholes and all preliminary & statically
tested working piles are to be selected randomly and tested by
i) Continuous supervision on site by engineer and the contractor is mechanical calliper logging (ASTM D 6167 – 11 & ASTM D 5753
always necessary to ensure that the piles are properly executed. – 95e1).
j) Care to be taken to ensure that there will be no displacement or - Steel reinforcement and concrete strength and durability shall
distortion of reinforcement during the formation of the pile. be tested as per QC Guidelines.

1.6.3 PILES TESTING

Piles testing shall conform to the following minimum requirements:
a) At least one for each pile diameter, non-working pile shall be tested,
to 200% of the pile’s working load. BS 8004:1986, Section 7.5.5 or
ASTM D 1143/1143M. Osterberg cell can be accepted only in the
preliminary test.
b) 1 % of the total number of working piles and minimum one test for
each pile diameter/type shall be statically tested to not less than
150 % of the pile’s working load, BS 8004:1986, Section 7.5.5 or
ASTM D 1143-89.
c) 5 % of the total number of working piles shall be tested using high
strain dynamic method to not less than 150 % of the pile’s working

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