Research On Out-of-plane Mechanical Properties Of EPSC Latticed Infill Wall

The expansive polystyrene granule cement form latticed concrete wall (EPSC latticed wall for short) which integrates the expansive polystyrene granule cement form and the interior latticed concrete framework together is a kind of composite wall, which has lightweight, thermal, sound insulation, fire resistance and load-bearing features. It has a broad application prospect in seismic regions of the cold northern of China. This paper analyzes the out-of-plane mechanical properties for the composite walls as retaining walls:1Finite element models for the latticed column are modeled by SOLID65for ANSYS. The mechanical properties of the latticed columns are analyzed through nonlinear numerical simulation for the uniform load of wind and the horizontal storey displacement of earthquake, respectively, and obtains that the latticed columns have remarkable large bearing capacity and deformability. The conclusion is drawn that the arching action after local cracking is the main reason for the improvement of the out-of-plane performance.2For the latticed walls under out-of-plane horizontal uniform load, theoretical analysis are performed based on two different assumptions on strains at the compression cross-sectional area and a simplified three-hinged model, considering the changes of the ratio of height to diameter of the columns and the gap at the top of the wall. Results show that the simplified three-hinged model could well reveal the wall’s arching action. The greater the ratio of height to diameter of columns is, the smaller the arching force and the out-of-plane loading capacity are. They decrease with the increase of the gap width, and the loading capacity might still be nice when the gap width is rational limited.3For the latticed walls under out-of-plane horizontal storey displacement, the article suggests a simplified two-force bar model for the arching action analysis, and the two varying conditions of the ratio of height to diameter of the column and the gap are also considered. Results show that the two-force bar’s arching action protects the wall’s collapse after cracking. The greater the ratio of height to diameter of columns and gap width are, the smaller the deformability and the bar’s arching action are. The wall’s deformability might still be nice when the gap width is reasonable limited.4Considering the common connection pattern style of infill walls that allows gap at top and links compensatory by tie-bars, of which the arching action is absence, a simplified calculation method that simplifies the connection as a hinge is proposed and the correction formulas for inner-forces of the latticed column and tie-bars are given.