兰州北环路上沟大桥抗震设计

Seismic Design of Shanggou Bridge of Lanzhou North Loop Road

研究目的:兰州北环路东段上沟大桥为5×30 m结构连续T梁桥,地震基本烈度为8度。本文结合2012年最新实施的《城市桥梁抗震设计规范》,通过对E1、E2地震作用下全桥动力特性分析,对桥梁相应部位分别进行能力保护构件计算和延性设计。研究结论:通过研究得出:(1)2011版《城市桥梁抗震设计规范》是2008版《公路桥梁抗震设计细则》的细化和提升;(2)对于允许进入塑性工作状态的桥梁设计,可以按照首先通过加大截面尺寸来控制变形量,再通过调整配筋率来使墩身部分屈服,最后进行能力保护构件设计这一流程进行。

Research purposes： The Shanggou Bridge in the eastern section of the Lanzhou North Loop Road is a 5 x 30 m continuous T beam bridge with seismic - resistant capacity of 8 magnitude. In this paper, according to the latest version of the ＂ Code for Seismic Design of Urban Bridge＂ implemented in 2012 and the analysis of the dynamic characteristics of whole bridge under the E1 and E2 seismic effects, the calculation of ability - protecting components and ductility design were made separately to the corresponding parts of the bridge. Research conclusions：From the research, we can draw the below conclusions： （1）The differences and the relation between the seismic rules of the highway bridge stipulated in the new version code and the 2008 version code can be seen. （2） For calculation of the bridge with the plastic working state, the following procedure should be followed ： First, the section dimension can be increased to control the deformation, then the rate of reinforcement can be adjusted to make the piers yielding and finally the capability protection members are designed.