Insulated precast concrete sandwich panels under punching and bending

摘要

Precast concrete sandwich panels can serve dual purposes of transferring loads and insulating the structure. A survey of the literature indicates that feasibility studies on the use of precast concrete sandwich panels to resist punching load are not reported. This paper presents the results and discussions of experimental and analytical studies conducted on two prototype precast concrete sandwich panels to determine and compare the behavior of precast concrete sandwich panels under punching and bending loads.The precast concrete sandwich panels consisted of top and bottom reinforced concrete wythes connected using continuous truss-type shear connectors and expanded polystyrene as the core. During the experiments, load-deflection curves and strains in concrete surfaces and wire mesh and reinforcing bars were monitored until panel failure. Test results indicate that the type of flexural loading conditions has a significant effect on the flexural behavior of these types of sandwich panels, in particular the failure mode, after a specific applied load magnitude and bending moment. Analytical studies indicate that the ultimate flexural load capacity predicted using the ACI 318-11 strength equation is comparable to that of experimental ultimate flexural load of the panel subjected to punching. Further studies are required in this area, in particular, developing design guidelines to use these panels as floor panels in housing systems.