Experimental Research On Mechanical Properties Of High Damping Rubber Bearing Under Multiaxial Loading State

High damping rubber bearing has been gradually used in actual engineering structures due to its environmental protection and good mechanical properties.In the past studies related to the mechanical properties of bearings,experiments were conducted under the unidirectional horizontal with constant vertical load.The coupling effect of horizontal restoring forces and vertical load are not negligible,since bearings are under multiaxial loading state in actual earthquake.Hence,mechanical properties of high damping rubber bearing under multiaxial loading state are investigated to satisfy the requirement of practical engineering.The main content of the paper is as follow:(1) The unidirectional horizontal test on HDR was conducted to investigate the influence of vertical load and shear strain on the equivalent horizontal stiffness, equivalent damping ratio, post-yield stiffness and yield strength.(2) The bidirectional horizontal test on HDR was conducted to investigate the influence of vertical load and shear strain on the mechanical properties parameter of the two horizontal directions.By comparing the values of the unidirectional horizontal test with the bidirectional horizontal test,the coupling effect of horizontal restoring forces are investigated.(3) The bidirectional horizontal test,the figure eight-shaped path,on HDR was conducted to investigate the influence of vertical load and shear strain on the mechanical properties parameter of the two horizontal directions.By comparing the values of the two experimental conditions,the effect of the Y direction displacement on the mechanical properties of HDR in the X direction are investigated.