The dynamic shear capacity of concrete structures

A. Ansell, Royal Institute of Technology (KTH) Stockholm, Sweden

For shear capacity, the current design procedure used for concrete structures has been found to be inaccurate for some dynamic design load cases. Loads traditionally believed to be highly dynamic are only within the quasi-static range, but it is known that the combination of a high impact velocity and a hard, stiff impact will lead to shear failure. Load cases on concrete structures which can be classified as dynamic are, for example, those relating to weapons and hard impacts from steel objects. The characteristic of a dynamic load has great influence on the overall response and mode of failure of concrete structures. When structures which have been designed to fail in flexure under static loads fail in shear when loaded dynamically, the reason is probably the changing frequency content of the load. On the basis of a literature review, some important conclusions and recommendations are presented in this paper. The results will be used in further evaluation of existing design tools, aiming at accurate and reliable routines for the design of safe and cost-efficient concrete structures.