EXPERIMENTAL RESEARCH ON SEISMIC BEHAVIORS OF ECOLOGICAL COMPOSITE WALLS BASED ON THE CHANGE OF KEY PARAMETERS

The aseismic behavior of four 1/2 scale models of ecological composite walls with straw nippy blocks is tested under low-frequency cyclic loading. The stress characteristics and failure mechanism of the specimens are researched. Besides, the aseismic performance comparative analysis on the ecological composite walls with different change of key parameters are made, such as bearing capacity, hysteretic loops, displacement ductility, deterioration of strength and stiffness, energy dissipation and so on. The experiment results show that the straw nippy blocks, ribbed grids and end frames in ecological composite walls play very important roles in turn in an elastic stage, an elastic-plastic stage and a failure stage of the experiment, which indicates that the ecological composite wall has several seismic defending lines. The ECW-3 wall, in which the distance is small between ribbed grids, is flexural failure; the ECW-4 wall, in which the height-width ratio is bigger, is flexural- shear failure; ECW-3 and ECW-4 walls are unfavorable failures. The ribbed grid divided and height-width ratio controlled should be focused on in the design process of ecological composite walls. The equivalent viscous damping coefficients of four walls all have obviously increased from a yielding stage to a failure stage, and that have great energy dissipation capacity .