摘要
依据框架锚杆支护体系的作用机理,在建立分析模型时分为2步,即把框架锚杆支护边坡结构体系分为动土压力模型和框架锚杆支挡结构动力模型2部分。一是考虑坡高对动土压力分布的影响,认为地震时作用在支挡结构上的土压力,在支挡结构顶部最大,向下逐渐减小,呈倒三角形分布。二是基于Penzien提出的集中质量法,将框架结构离散化为质点串,而锚杆以弹簧支座形式将框架与土体进行连接,取一榀框架柱为计算单元,建立相应的动力模型控制方程,通过振型分析建立振型方程,并求解振型反应。通过对动土压力的求解和框架结构振型反应的分析,可以得到框架各结点处的支座反力,从而为框架锚杆支护边坡的抗震设计提供一定的依据。
According to the working mechanism of a supporting system with frame-anchors,its analysis model is divided into two phases,namely the dynamic soil pressure model and dynamic frame-anchors model.Firstly,the influence of slope height on seismic soil pressure distribution is considered.The soil pressure acting on the supporting structure is regarded as inverse triangles on the condition of earthquake.The maximum pressure locates at the top of the wall and decreases gradually from top to bottom.The frame-anchors analysis model consists of a set of discrete lumped masses based on the concentrated mass method proposed by Penzien.The frame structure and soil are connected by anchors with spring supports.The corresponding control equation of motion is established by taking the frame-columns as a calculating unit.The modal equation is established and modal response is solved through modal analysis.The support reaction of each node can be obtained based on the solution of dynamic soil pressure and the analysis of modal response.The results of dynamic soil pressure and modal response can provide a reference for the seismic design of slope supported with frame-anchors.
出处
《工程力学》
EI
CSCD
北大核心
2011年第12期27-32,38,共7页
Engineering Mechanics
基金
国家自然科学基金项目(50978129)
关键词
框架锚杆
支护边坡
动力模型
地震作用
振型分析
frame-anchors
supporting slope
dynamic model
earthquake action
modal analysis
