Consequences of excessive deformation of structural elements in precast buildings

Abstract

The work concerns the phenomenon of damage to internal partition walls in typical prefabricated residential buildings. As a construction system, large-panel buildings were very popular all over Europe at the end of the 20th century. Defects in structural members or layer joints in facade wall panels have been investigated many times. The neglected aspect of the operation of large-panel buildings are the consequences of excessive deformation of structural elements progressing over time, e.g., deflections of prefabricated floor slabs.The safety of building residents is determined not only by the fulfillment of the limit states conditions by basic structural elements, e.g. external walls or floor slabs. Failures can also occur as a result of damage to partition walls. Initially rigid floor slabs remain supported only at the edges of the structural walls, while in the middle zones they are deflected. Partition walls, made of various materials, are subjected to shear stress in addition to compression. This can result in cracks and even destruction of the wall structure.The problem presented for discussion was confirmed by the case of a real failure of partition walls in a building operated for more than thirty years. To find explanation and reasons of such a phenomenon, numerical calculations were carried out for partition walls and for prefabricated floor slabs that are under and above the analyzed wall. In the case of partition walls, the effort of the wall material was considered in terms of exceeding the ultimate limit state in the tensile zones. For the floor slabs the deflection values were determined. The implemented concept of an effective reconstruction of the wall structure has been also described.