基于板式 GFRP 剪力连接件的预制混凝土三明治板的组合度研究

Based on existing static tests of concrete sandwich panels with plate-type glass fibre-reinforced polymer (GFRP) shear connectors, two different percentages of composite action were firstly analyzed using the member stiffness and the member strength as the indices, respectively. Three-dimensional finite element (FE) analyses were then conducted based on the commercial software package ANSYS to reproduce the full-range load-deflection behavior of the composite panel specimens. Based on the validated FE model, parametric studies were further conducted to investigate the effects of the GFRP shear connectors' layout, their material property and their geometrical dimension on the stiffness of the sandwich panel. The obtained stiffnesses were then compared with the theoretical values of fully composite sandwich panels, where the ratio of the two was defined as the percentage of composite action of stiffness (PCAS). The FE results indicate that: the PCAS of sandwich panels increases with the global shear stiffness provided by the GFRP shear connectors in the shear span while the increasing rate reduces gradually; with the increase of the insulation thickness, the PCAS decreases with the increase of the plate thickness of the GFRP shear connectors while the decreasing rate reduces; and the parameters of the GFRP shear connectors influence more significantly the PCAS than the percentage of composite action of strength of the sandwich panel. Since it is hard to use the plate-type GFRP shear connectors to realize a full composite action of the sandwich panel, stiffness reduction should be carefully considered during a practical design.