Research On The Technology Of Sliding Isolation With Regenerated Rubber Displacement-limited Blocks In Rural Buildings

Most houses in villages and towns are low-rise buildings,most of which were not designed and built according to the seismic fortification requirements.And these buildings can be severely damaged or even collapsed in an earthquake.According to the economic situation in rural areas,a new type of simple isolation device which is suitable for low buildings in villages and towns,friction sliding isolation with regenerated rubber displacement-limited blocks(RRB),is proposed.Through the uniaxial tensile test of the standard sample,the key parameters in the constitutive model of the regenerated rubber are determined;according to the construction of the isolation device and the compression characteristics of the rubber material,the arrangement methods and size of the RRB are proposed;with the use of ABAQUS software,the compression stiffness characteristics of the RRB are analyzed,and the restoring force model of the isolation layer is proposed;finally,with the use of SAP2000 software,the seismic response of the upper structure of two-story masonry building in isolation and non-isolation state are analyzed,and the isolation effect and limit effect of this device are studied.The results show that:(1)Based on the uniaxial tensile and compression test data,by analyzing the biaxial and plane test data with ABAQUS finite element method,the constitutive relationship of the regenerated rubber material can be obtained.(2)The compressive force-displacement curve of RRB is nonlinear,and the compression stiffness increases with the increase of compressive force.The curve is roughly divided into three sections.In the initial stage it shows basically a straight line,with small stiffness.In the middle stage,the stiffness starts to increase.And in the later stage,the stiffness increases sharply.The curve can be simplified to six straight lines,that is,the stiffness of RRB can be simplified to "six linear".In SAP2000,this curve can be simulated with six Gap elements with different stiffness and slit width in parallel.(3)For the two-story masonry structure building with friction sliding isolation and RRB device,the seismic response is 60% less than that of the non-isolation building under the design earthquake.And the displacement of the isolation layer under the rare earthquake is controlled below 100 mm.RRB plays a role of limit and also provides the restoring force.(4)The isolation layer with friction slip and RRB has better isolation effect by setting up a self sliding section.The length of the self sliding section should not be less than the displacement of the isolation layer under the action of small earthquake.