高阻尼橡胶隔震支座力学性能研究及其桥梁工程应用进展

Mechanical Properties of High Damping Rubber Isolation Bearings and its Application in Bridge Engineering

高阻尼橡胶支座(High-damping Rubber Bearing, HDRB)是一种新型耗能型减隔震支座,由于其隔震效果好、耗能能力强和对环境无污染等优点而逐渐应用于减隔震桥梁工程中。以HDRB为研究对象,分别从主要组成材料高阻尼橡胶(HDR)、支座力学性能和隔震桥梁工程应用三个方面进行阐述,分析和总结HDRB力学性能及工程应用的现状、机遇和挑战。对HDR的力学特点和相关本构模型进行了介绍,指出当前理论大多忽略了HDR大变形前后内部的分子变化和应变速度相关性;阐述了HDRB的力学性能和当前已发展的本构模型研究现状,指出HDRB的力学性能受应变和频率的影响最大,工程中普遍采用双线性本构模型,但该模型无法准确描述HDRB的非线性力学行为,发展考虑诸多工程因素的HDRB选取依据和简单有效的力学模型是有必要的;最后,总结了当前国内外HDRB隔震桥梁工程应用研究进展,建议应更加关注速度敏感的HDRB隔震桥梁在近断层地震动下的动力响应、HDRB在桥梁中的脱空现象以及竖向隔震性能等问题。

High damping rubber bearing(HDRB)is a new type of energy dissipation isolation bearing,which has been gradually applied in bridge vibration isolation control because of its good isolation effect,strong energy dissipation ability and no pollution to environment.Firstly,we analyzed and the summarized the status,opportunities and challenges of mechanical properties and engineering applications of HDRB from three aspects,such as the main component material of high damping rubber(HDR),mechanical properties of bearings,and engineering application of seismic isolation bridges.Secondly,basing on the study status of mechanical characteristics and constitutive models of HDR,we found that most of the current theories ignore the correlation between the strain rate and internal molecular changes before and after large deformation of HDR.Through studying the mechanical properties of HDRB and the research status of the developed constitutive models of HDRB,we also proposed that the mechanical properties of HDRB can be most affected by strain and frequency.The bilinear constitutive model is widely used in engineering,but it cannot accurately describe the nonlinear mechanical behavior of the HDRB.Therefore,it is necessary to propose the selection basis of HDRB considering many engineering factors and a concise and effective mechanical model.Finally,based on the above two aspects,we summarized the related research progress of HDRB isolated bridge at home and abroad.It is suggested that more attention should be paid to the dynamic response of velocity-sensitive HDRB-isolated bridges under near-fault ground motions,the void phenomenon and vertical isolation performance of HDRB in the bridge etc.