Lessons Learned from the Disaster at Lippe Canal Bridge

In October 2005, during construction works at the new Lippe canal bridge, massive water leakage from the Dortmund-Ems-Canal occurred below a wing wall at the northern abutment of the old, still operated canal bridge. Water passed through a leak of the claylined canal, flowing underneath a pile-supported wing wall into a minor excavation pit. This excavation pit was supposed to be protected by a surcharge filter. Since failure of the lining should be considered for all construction phases, it cannot be regarded as the cause of the disaster. Consequently, the paper focuses on the verification against hydraulic heave and erosion for the excavation pit. It is demonstrated that Terzaghi’s statements on this topic remain valid and should not fall into oblivion