大跨度预应力混凝土铁路连续梁桥地震响应及减隔震研究

【作者】 张辉；

【导师】 戴公连；

【作者基本信息】 中南大学 ， 桥梁与隧道工程， 2008， 硕士

【摘要】 本文对铅芯橡胶支座的力学模型和减震效果以及如何选择支座进行了研究,以武广客运专线陈村水道铁路连续梁特大桥(70m+125m+70m)为工程背景,研究了各种因素对三跨连续梁隔震桥的隔震效果的影响,采用正交设计法和功效系数法对支座参数进行优化。主要工作和结论包括以下方面:1.根据铅芯橡胶支座的实际受力特点,比较了目前常用的几种分析模型的优缺点,并采用有限元软件Midas非线性弹簧单元模拟了铅芯橡胶支座的双线性滞回特性。2.以陈村水道桥为背景,系统讨论支座布置方案、梁墩的刚度、减隔震支座参数(K_u、F_y和η)、土-结构相互作用、地震波、场地条件和列车活载等因素对隔震效果的影响。3.以铅芯直径、橡胶直径和橡胶剪切模量为变量,采用正交设计法和功效系数法对陈村水道桥进行参数优化设计,并以此提出了一套切实可行的支座优化方法。4.将隔震前后的桥梁地震响应进行比较,包括自振特性、内力、位移等,并探讨了隔震对桥墩和基础设计的影响。更多还原

【Abstract】 The present paper gives a study on mechanical models of lead-rubber bearing (LRB) and seismic isolation effects by using LRB as isolation unit as well as how to choose it in real construction. Based on the analysis of ChenCun channel extra-long railway continuous beam bridge (70m+ 125m+70m) , the various effects on three-span continuous beam bridge by using LRB has been studied. Meanwhile, bearing parameters has been optimized by applying methods of orthogonal design and of efficacy coefficient. The main contents of this paper are presented as follows:1.On the basis of LRB’s actual stressed characteristics, the advantages and disadvantages of several frequently used models has been compared. Meanwhile, this paper present a simulation of bilinear force-deformation relation of LRB by non-linear spring element through finite element software MIDAS.2.On the study of ChenCun continuous beam bridge, the isolated effect by various factors has been studied, such factors as arrangement of bearings, the stiffness of beam and pier, parameters of isolated bearings (Ku, Fy andη) , soil-structure interaction, seismic waves, site conditions and train live load.3.On the basis of lead-diameter, rubber-diameter and shear modulus of rubber as variables, bearing parameters has been optimized by applying methods of orthogonal design and of efficacy coefficient. Meanwhile, this paper gives an effectual and practical method for bearing optimization.4. The impact of isolation in foundation design has been discussed in this paper.更多还原