FULL SCALE INSTRUMENTED PILE TEST IN THE NORTH SEA.

During the early spring 1976, BP carried out tests on an instrumented working pile on their FD structure of the Forties Field in 121 m water depth. The test was carried out on a 100 m long pile 1. 37 m diameter. The purpose was to provide data on the influence of the many constraints on the transmission of a pile driving stress wave with a view to eventual improvement in analytical tools using wave equation techniques. The test pile was instrumented with strain gauges, accelerometers and pore water and total pressure cells at various levels. The data has been interpreted in engineering terms for selected blows of different hammers and compared with theoretical predictions using both conventional and modified wave equation analysis. Total and pore water pressure measurements were made at three levels on the pile and the results are presented in the paper.