Keynote lecture: Oresundlink, grouting work under West Pylon: Integrity test of a giant pile

摘要

Integrity tests were performed at the West Pylon caisson of the high bridge in the Oresundlink between Sweden and Denmark. The purpose of the tests was to investigate the grout filling works under the 0.9 m thick concrete bottom slab. During the grouting works a storm occurred which swept away approximately 1% of the underbase grout causing voids and gaps in the interface between the bottomslab and the grout. This circumstance jeopardised the bearing capacity of the caisson. The bond between the slab and the grout should be at least 80% according to contract. The investigation showed that this demand was not fulfilled. First after intense grouting works the 80% connection was achieved. The Non-Destructive tests using low strain integrity method were covering the 35 x 37 m bottom slab. Tests were also performed in the verification phase after the repair works were completed.