The Collapse and Reconstruction of a Prestressed Concrete Box-Section

During the construction of a prefabricated roof, a 25 m long prestressed box-section girder collapsed. The major cause of the failure was an inadequate structural design of the support regions. There was no transverse end beam present and support bearing points were not placed beneath the webs of the girder. The resulting transverse bending together with insufficient end anchorage led to the collapse. 45 similar beams, of which half were already erected, were in consequence locally strengthened in the support regions. Thus an original remedial solution, scarcely externally visible, was developed and tested through an on-site load test.