Failure of Hollow Ribbed Slabs in Buildings – Suggested Rehabilitation Method

In 2001 a major structural collapse took place in a four story building in Jerusalem, Israel. The tragic event brought to an end the implementation of a ribbed slab construction method that, although not conforming to the concrete code, and in spite of criticism by the professional media for years, found it way to the market. Most of the buildings using these slabs are in need of rehabilitation (or in extreme cases, should be demolished) due to grave deficiencies in the method. In the f ollowing, the deficiencies of this construction method are outlined and a rehabilitation scheme presented. The rehabilitation method aims at enhancing shear and flexural strength in the existing slabs. The views expressed in this paper, as to the structural concept and its deficiencies, are those of the authors.