Chapter 9: Structural Robustness

The design of a building to be robust is an essential part of good structural design. Nominally, buildings may be stable under normal actions but abnormal actions – such as accidental damage, unexpected structural movement or the effects of poor quality control in construction – can produce consequences that are disproportionate to the initial event. The design of buildings to be robust has been a central part of UK design since the late 1960’s and is a key requirement of UK/European and US design standards. This chapter introduces the concept of structural robustness and building failure, covering the methods of failure commonly seen such as progressive collapse and failure due to ongoing material or serviceability issues leading to deterioration of all, or part of the structure. It will discuss the requirements of suitable building foundations and the cause and effect of external environmental issues on the substructure and the requirement for adequate pre-construction investigations. The analysis, design and detailing of buildings will be discussed as will the importance of adequate knowledge and experience of the design and checking engineers which should be relevant to the project being undertaken.