超低硬度橡胶隔震支座力学性能的有限元分析

对G值约为0.196 MPa、直径600 mm的超低硬度天然橡胶隔震支座(LNR)和铅芯橡胶隔震支座(LRB)在竖向压应力作用下进行了有限元(FEA)初步数字模拟研究。建立了支座的精细有限元模型,并对其基本力学性能的有限元计算结果与理论计算结果、试验结果进行了对比,吻合较好,侧面验证了计算模型的正确性。通过对LNR和LRB在竖向压力下的有限元数值分析模拟,研究了天然橡胶隔震支座内部钢板应力特征、内部橡胶应变特征、铅芯橡胶隔震支座中铅芯应力特征、铅芯与内部钢板及内部橡胶的相互作用机理。LNR支座FEA初步分析表明,因硬度超低,靠近孔壁处内部橡胶在竖向压应力下较早表现出较大非线性,内部钢板在孔壁处较早出现一定程度的应力集中。LRB支座FEA分析中表明,铅芯与内部橡胶、内部钢板相互作用明显。

FEA study on mechanical property of elastomeric isolators with ultralow hardness

For LRB and LNR with shear modulus about 0. 196 MPa,diameter 600 mm,preliminary FEA on them loaded with compression were carried out. An accurate finite model was established,the discrepancy among the theory results,the test results and the FEA results was very little,it testified the accuracy of the FEA model. The FEA models of LNR and LRB loaded by the vertical pressure were performed,the research concern including stress of inner steel and strain of inner rubber in LNR,stress of lead-core and interaction between lead-core and inner steel,inner rubber in LRB. It is concluded that non-linear feature will early appear in the inner rubbers near core during FEA,stress concentration appears in the inner steels near core because of lower hardness of rubber. Apparent interaction between lead- core and inner steel,inner rubber will also be found in FEA on LRB.