Back-analysis of pile load test results – a case study

Caution is required in selecting the safe load carrying capacity of bored piles, even if a few test piles indicate substantially higher capacity than theoretically estimated from static analysis. The consequences of failure of working piles should be evaluated carefully to select suitable safe load carrying capacity for design. Use of pile capacities higher than the computed values should be backed up by sufficient static and dynamic pile load tests and integrity tests. A case study illustrating static and dynamic load tests on piles installed in alluvial sands demonstrates the design methodology to be followed.