Bending Performance of Concrete Sandwich Walls with Actual Boundary Conditions

Concrete sandwich walls are commonly used as the exterior wall panels of a structure, in which the wall suffers out-of-plane bending under strong wind conditions. This paper aims to investigate the bending performance of concrete sandwich walls under actual boundary conditions through experimental and analytical methods. In total, four concrete sandwich walls were tested to detect the influence of openings and loading direction. Typical failure patterns were characterized and discussed. The load-displacement curves of four test specimens were analyzed. It was indicated that the bearing capacity of the walls under negative bending conditions was higher than that under positive bending conditions, owing to the additional constraints provided by the steel beams. Strain distributions of wall specimens were also discussed in order to obtain the composite action of the sandwich walls between the upper and lower layers of concrete. In addition, the finite element model (FEM) was developed by ABAQUS to provide insights into the bending performance of the sandwich walls. Through comparison with the test results, the FEM was verified with a good level of accuracy. Subsequently, the degree of composite action of the sandwich walls was assessed in terms of both the moment of inertia and bearing capacity. From the experimental and numerical results, it demonstrated that the bearing capacity of concrete sandwiched wall under negative direction was higher than that under positive direction owing to the constraints of steel beam. The derived composite action degree could be employed to evaluate the out-plane bending stiffness and strength of sandwiched concrete wall. Both the experimental and analytical results in this paper are beneficial for the design of sandwich walls under bending conditions.