梁式桥板式橡胶支座的合理计算模型研究

Study of Rational Calculation Model for Beam Bridge with Laminated Rubber Bearings

为寻求合理的板式橡胶支座梁桥计算模型,以准确计算其受力情况,基于板式橡胶支座关键参数的计算理论,以20m简支梁桥和3×20m连续梁桥为例,采用MIDAS Civil建立2座梁桥空间模型,分析3种计算模型(理想约束模型、弹性约束模型和简化约束模型)在恒载和活载作用下主梁关键截面的弯矩、剪力、位移及挠度。结果表明:对于简支梁桥,理想约束模型与弹性约束模型的计算结果(除个别截面)相差在5%以内,板式橡胶支座梁桥可按理想约束模型近似模拟;对于连续梁桥,理想约束模型与弹性约束模型的计算结果相差超过5%,简化约束模型与弹性约束模型的计算结果相差在5%以内,板式橡胶支座梁桥可按简化约束模型近似模拟。

To select rational calculation model for the beam bridge with laminated rubber bear-ings and accurately calculate the load bearing behavior of the bridge, a 20 m long simply-supported beam and a 3× 20 m continuous beam bridge were taken as examples. Based on the calculating the-ories of the key parameters of laminated rubber bearings, the spatial models of the two beam bridg-es were established by the MIDAS Civil software, to analyze the bending moment, shear force, displacement and deflection of the key cross sections of the main girder of the three calculation models under the actions of dead and live loads, including the ideal restriction model, elastic re-striction model and simplified restriction model. The results indicate that for the simply-supported beam, the difference between the results gained from the ideal restriction model and those gained by elastic restriction model （excluding some exceptional cross sections） is within the range of 5 % , and the beam bridge with laminated rubber bearings can be approximately simulated by ideal re-striction model. To the continuous beam bridge, the difference between the results gained from the ideal restriction model and those by the elastic restriction model exceeds 5 % , and the difference be-tween the results gained from the simplified restriction model and those by the elastic restriction model is within 5 % , and the beam bridge with laminated rubber bearings can be approximately simulated by the simplified restriction model.