基于橡胶隔震支座老化作用的近海隔震桥梁地震响应时变规律

通过对橡胶隔震支座进行海洋环境下的老化时变规律试验和理论分析研究,得到橡胶隔震支座在海蚀环境下的性能劣化规律。利用钢筋混凝土材料和隔震支座材料的劣化模型,采用SAP2000软件建立近海隔震桥梁的非线性动力分析模型。定义墩柱劣化、橡胶隔震支座劣化及二者共同劣化三种劣化工况,对桥梁在全寿命周期内的地震响应的时变规律进行分析。结果表明:墩柱材料和支座性能单独劣化均会显著影响桥梁的地震响应,而二者共同劣化的响应结果取决于单一因素的结果。总体来看,随着劣化时间的增大,墩顶最大位移增大,支座水平最大剪切位移减小,墩柱塑性耗能增大,支座滞回耗能面积减小。研究可为桥梁结构全寿命抗震性能分析和评估提供理论依据。

Study on the Time-dependent Law of Seismic Response of Offshore Isolated Bridges Based on the Aging Effect of Rubber Isolation Bearing

The performance degradation with aging time of the rubber isolation bearings in the sea erosion environment was obtained by the time-dependent regularity test and theoretical analysis. Using the performance degradation law of reinforced concrete and rubber isolation bearings, the sap2000 software was used to establish the nonlinear dynamic analysis model of the offshore isolated bridge. The three deterioration conditions of the deterioration of the piers, the deterioration of the rubber isolation bearings and the common deterioration of the two were defined, and the time-dependent law of the seismic response of the bridge during the whole life cycle was analyzed. The results show that the degradation of the piers and the bearings performance will significantly affect the seismic response of the bridge, and the response of the two degraded depends on the single factor. In general, as the deterioration time increases, the maximum displacement of the pier top increases, the maximum shear displacement of the bearing decreases, the plastic energy consumption of the pier increases, and the energy consumption area of the bearing decreases. This study provides a theoretical basis for the analysis and evaluation of the whole life cycle seismic performance of bridge structures.