国内外延性抗震设计的比较

1971年美国发生圣.费尔南多地震,许多新建的桥梁结构遭到严重破坏之后,延性抗震得到重视,抗震设计方法正在从传统的单一强度理论向延性抗震理论过渡。目前,大多数国家的桥梁抗震设计规范已经采纳了延性抗震理论。本文针对几个主要的抗震设计规范,包括EC8、Caltrans、AASHTO、日本和我国公路桥梁抗震设计规范中的延性抗震设计做一个概述。主要内容有延性指标的定义及其计算方法和延性构件钢筋锚固和搭接长度的规定,本文对我国公路桥梁的延性抗震设计有一定的参考价值。

Comparing overseas and inland specifications for ductility seismic design

Engineers were shocked to observe that modern highway bridges were destroyed in the 1971 San Fernando,California,earthquake.After that,ductility seismic design attracts more attention,and the research turning simple intensity design to intensity ductility design method was started.The ductility seismic theory has been written into overseas and inland seismic specifications for highway bridges.In this paper,the ductility seismic design is introduced and the differences among several seismic specifications for highway bridges including EC8,Caltrans,AASHTO,specifications of Japan and China will be discussed.This includes the definition and calculation of ductility index,the details of ductile members,such as the length of inelastic hinge,the requirements of splices and the anchor of reinforcement at plastic hinges.