Load bearing capacity of prestressed concrete hollow core slabs taking into account tensile membrane action

Tensile membrane action can considerably enhance the load-carrying capacity of longitudinally restrained concrete slabs. This additional capacity could delay, or even prevent, a structural collapse, and is therefore considered an important mechanism for increasing the robustness of concrete structures. Unlike reinforced concrete members, this beneficial effect is rarely considered in case of prestressed elements, such as precast hollow core slabs. Consequently, the reserve capacity of these commonly used floor elements due to tensile membrane action is a relevant topic for further investigations. Therefore, this paper investigates the beneficial effects of tensile membrane action in axially restrained prestressed concrete hollow core slabs. To this end, a detailed finite element model is developed in Abaqus. Numerical 4-point bending tests are performed to obtain the cracking patterns, displacements and failure loads. Subsequently, a brief parametric study is conducted to investigate the influence of the ultimate failure strain of prestressing steel on the ultimate load-carrying capacity of axially restrained concrete hollow core slabs taking into account tensile membrane action. The results indicate that tensile membrane action can, to some extent, enhance the load-carrying capacity of prestressed concrete hollow core slabs. However, the additional capacity that can be achieved strongly depends on the boundary conditions and the depth of the member