桥梁工程安全性与耐久性——展望设计理念进展

范立础

(同济大学桥梁工程系)

摘要:本文通过对国内外桥梁运营维护所付出的惨重代价和发生的桥梁事故的研究基础上，分析了影响桥梁安全和耐久及造成桥梁事故的因素。基于此，作者提出了提高桥梁安全和耐久的两个必要措施：一是要有不断健全的规章、规程、制度和建立科学的管理体系，其能确保桥梁工程的质量，质量是结构安全与耐久的最基本的要求；二是应该力图开展保障结构安全与耐久的新设计理念的研究：认识到结构各部件的寿命不是完全相同的，因而结构寿命期内功能的保证，必须从设计、施工、材料、检测、维修、加固整个过程来考虑，审视结构的概念设计与构造设计，并保障结构在生命期内的结构可检性（Examinability）、可换性（Replaceability）、可修性（Repairability）、可控性（Controllability）、可强性（Retrofittability）和可持续性（Sustainability）。最后作者分析了实施桥梁新设计理念过程中的科学决策关键技术——进行桥梁风险评估，保险是减少风险的有效措施。实质上引入了寿命投资效益的新概念。

关键词：桥梁事故，设计理念，风险评估，结构寿命期

                          Safety and Durability of Bridge Engineering

                  —— progress of design concept in prospect

Lichu Fan

Abstract:Based on the study of bitter and tremendous costs paid in managing and maintaining bridges as well as bridge accidents at home and abroad, factors that influence the safety and durability of bridge Engineering and that cause the bridge accidents are analyzed. In this paper, two indispensable measures to improve the safety and durability of bridges are suggested: firstly, rules, codes and institutions should be constantly strengthened and scientific management system established, which can guarantee the quality of bridge engineering and the quality is the most fundamental requirement of structural safety and durability; secondly , researches using new design concept that can ensure the structural safety and durability should be carried out. Being aware of that lifespans of structural components are not the same, therefore, in order to guarantee the service function during the structural lifespan, the whole procedure consisting of designing 、constructing、materials’ selecting、monitoring、repairing and retrofitting must be taken into account; at the same time, the concept design and construction design of structures should be investigated, and the structural examinability,  replaceability, repairability, controllability, retrofittability and sustainability within structural lifespan must be ensured. Finally, bridge risk assessment, the key technique of scientific decision-making, using the new design concept in the bridge design process, is surveyed. And insurance is an effective means to reduce the risk. Actually, a new concept of using investment benefit in the bridge life cycle is introduced.

Keywords: bridge accident, design concept, risk assessment, structural lifespan