Abstract：Finite element software ABAQUS was used for analyzing the influence of boundary condition, such as shear strength of damping layers and hardness of filler in flexible side, on working mechanism and performance of damped infill wall (DIW) under monotonic static loading. Additionally, the working mechanism was revealed and the suggestions for design were given. The results show that, there are six various types of out-of-plane working mechanism under different boundary condition. The out-of-plane arching action along both the height and width of DIW forms under the boundary condition that the shear strength of damping layers and the elasticity modulus of filler in flexible side is larger than 1.2MPa and 1.5MPa respectively. Under this boundary condition, the working mechanism is reasonable, the peak loading and initial stiffness is the largest among other working mechanism. Each masonry unit of DIW moves as a rigid body and the out-of-plane deformation concentrate on the two damping layers as well as the middle masonry unit. Under various boundary condition, the deformation mode mainly presents three types of shape as followed, bilinear, trilinear and the shape between bilinear and trilinear. The force mainly transfers along the height of DIW instead of the width when the compressive strength of damping layer constructed by the low strength mortar is larger than 1.2MPa. It is suggested that the compressive strength of damping constructed by the low strength mortar is expected to be greater than 1.2MPa. The filler in the flexible side is suggested to constructed by using M1.5 mortar or other material of which the elastic modulus is greater than 1.5MPa.
