大跨度桥梁抗震设计实用方法

本文是为了配合"城市桥梁抗震设计规范”的制订而进行的,目的在于给桥梁工程师们提供一个能参照执行的大跨度桥梁抗震设计方法,以及可靠实用的辅助工具.在总结学科组多年的研究成果和实践经验的基础上,根据两水平的抗震设计方法和能力设计思想,发展了大跨度桥梁抗震设计实用方法,并开发了相应的辅助工具(IPSABS软件).最后,介绍了一个大跨度桥梁抗震设计的实例.根据本文的抗震设计方法,并借助IPSABS软件,桥梁工程师们即可自行进行大跨度桥梁的抗震设计.

A PRACTICAL PROCEDURE OF SEISMIC DESIGN FOR LONG SPAN BRIDGES

Lot of seismic researches and practical designs are reviewed and summarized. A practical procedure for the seismic design of long-span bridges is procosed in the paper. It is based on the two-level design approach and capacity design principles. A bridge will be designed based on two performance standards, and in turn subjected to two levels of design earthquakes with different probability of occuring.This is called the two--level design approach.The basis of capacity design principle is that the seismic damage will be occurred at certain regions of the bridge that are designed and detailed for flexural ductility. It insures an adequate margin of strength between nonductile failure modes and the designed ductile mode of deformation. An integrated program for the seismic analysis for bridge system (IPSABS) is developed. Some practical examples are used to prove the reliability of the program.