采用有限元方法对直径为1500mm隔震橡胶支座内部钢板最大应力影响因素进行分析研究,提出了相应修正计算公式.影响因素包括支座内部孔洞的大小、单层内部橡胶与钢板厚度之比(tr/ts)、内部橡胶剪切模量(G)、支座第1形状系数(S1)以及支座外保护层厚度.研究对象包括建筑及桥梁用隔震橡胶支座,荷载方法采用单向竖向加载及压剪荷栽.研究结果表明,支座内部孔洞大小、tr/ts、S1对内部钢板最大应力影响较大,而G值及保护层厚度对其影响很小.提出了考虑5.影响、用以计算支座内部钢板最大应力的修正理论计算公式,并与有限元计算结果进行了对比,对比结果表明,无论是S1大的建筑隔震橡胶支座还是S1小的桥梁隔震橡胶支座,两者吻合较好.
In this paper, some factors affecting the maximum stress of inner steel plate of elastomeric isolator with big diameter of 1 500 mm are analyzed by FEA, and a modified prediction formula for the maximum stress of inner steel plate is proposed. These factors include size of hole, ratio of tr/ts, shear modulus of inner rubber G, the first shape factor S1 , thickness of cover rubber. The isolators include those which are to be used in build- ings or bridges, loading condition includes single compress and press-shear load. Research results show'that size of hole, ratio of tr/ts and S1 have a little effect on the maximum stress of inner steel plate, but shear modulus of inner rubber, and thickness of cover rubber hardly have effect. The modified prediction formula considering S1 effect shows a good correspondence with the FEA results for isolators which are generally to be used in buildings or bridges.