Behaviour of steel tube-reinforced concrete flat slab shearhead systems

A new shearhead system between a steel tubular column and a reinforced concrete flat slab has been developed. Compared with normal flat slab structure using reinforced concrete frames, this shearhead system allows thinner slab thickness, easier fabrication and shorter construction time. Two full-scale tests were conducted, one using a square steel tube and the other using a circular steel tube. The tests were simulated with the finite-element package Abaqus for validation of the numerical simulation model, which included load–displacement and load–strain curves, crack development and punching shear failure surfaces. A sensitivity study for the numerical model was carried out to examine the effects of different material properties and mesh sensitivity in order to select the most appropriate modelling parameters using Abaqus.