Instrumented pile load test: Some observations on local practice

摘要

Preliminary pile load test is usually carried out at the beginning of a piling contract. For the pile load test to be meaningful, it is usually instrumented. The pile instrumentation scheme will assist engineers in interpreting the soil-pile interaction behaviour of the pile, the unit skin friction of the various founding soil layers and the end bearing capacity. This will guides design engineer in the final design of a pile foundation system for a given project. However field instrumented pile, like any laboratory test, may be subject to inaccuracies. The understanding of the pile set-up and the way pile was constructed at the site is important. One of the factors is the equation used to analyze the instrumentation data. It involved parameters like cross-sectional area of pile and Young's modulus, which may be affected by construction method. This paper will present some local case studies of instrumented test piles. Through these case studies, factors that can affect test results will be presented. It wills highlights factors that may affect the instruments during installation and its results. This paper will also discuss why judgement of engineer is important when interpreting test result.