板式橡胶支座滑动摩擦性能试验及其力学模型

Experimental Study on Sliding Friction Behavior of Laminated Rubber Bearing and Its Mechanical Model

摘要:

针对汶川地震中小跨度梁桥出现的板式橡胶支座滑动的典型震害，对板式支座与钢板间的滑动摩擦性能进行了试验研究，分析了竖向正压力和滑动速率对支座滑动摩擦性能的影响规律，试验结果表明，在发生明显滑动之前，支座以水平剪切变形为主，伴随少量的相对滑动，其名义剪切模量在700~1 100 kPa之间；板式支座与钢板间的滑动摩擦系数与支座的竖向压应力呈负相关，与滑动速率呈正相关.最后建立了考虑板式支座与钢板间滑动摩擦性能的精细化力学模型，以考虑多种因素对支座滑动效应的影响.

Abstract:

Based on the typical damage of laminated rubber bearing sliding for small to mediumspan girder bridges during the Wenchuan Earthquake, experimental study on the sliding frictional behavior between bearing and steel plate was carried out. Effects of vertical stress and sliding velocity on the bearing sliding behavior were investigated. Results showed that the bearing displayed an approximately linear elastic shear response before sliding. The nominal shear modulus of the bearing ranged between 700 and 1 100 kPa. The coefficient of sliding friction at bearingsteel plate interface was negatively related to the vertical stress, and positively related to the sliding velocity. A mechanical model of the sliding behavior between laminated rubber bearing and steel plate was then developed, considering the effect of various parameters.