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Piles Engineering

It is not necessary to design nominal reinforcement to piles. Is it true?

In BS8110 and BS5400 Pt.4, they require the provision of nominal reinforcement for columns. However, for pile design the requirement of nominal reinforcement may not be necessary. Firstly, as piles are located
underground, the occurrence of unexpected loads to piles is seldom. Secondly, shear failure of piles is considered not critical to the structure due to severe collision. Moreover, the failure of piles by buckling due to fire is unlikely because fire is rarely ignited underground.

What are the head details of H-piles under compression and subject to bending moment?

For steel sections referred to in BS5950, universal bearing pile is characterized by having equal flange and web thickness while universal column has different flange and web thickness. Universal columns can also be used as bearing piles.

What are the functions of different reinforcement in a typical pile cap?

Loads from columns transferring to pile cap induce tensile forces at the bottom of the cap. For instance, by using truss analogy to analyze a pile cap sitting on two piles with a column at the centre of the pile cap, the tensile force at the bottom is proportional to the pile spacing and is inversely proportional to depth of pile cap. The bottom reinforcement is designed to resist the tensile stressed generated from loads in columns.


How does the pile installation method affect the load carrying capacity of piles?

The construction of piles by driving method causes an increase in density of the surrounding soils. Hence, for loose soils this results in improved compaction of soils between the piles.


Which of the following stages is noisier, at the ending of pile driving operation or at the end of pile driving operation?

When the piles are progressively driven into the ground, the pile section above the ground declines. As a result, the degree of damping on the piles increases. Moreover, the area of exposure of piling surface reduces, thereby reducing the area generating noise form piles. Hence towards the end of pile driving operation, the noise level shall be reduced accordingly.