基于可靠度理论预应力混凝土桥梁使用寿命预测研究  

Study of Service Life Evaluation Based on Probability Theory for Prestressed Concrete Bridge

作　　者：李杰[1] 陈淮[1] 江莹莹[1] 陆慧琳[1] 

机构地区：[1]郑州大学土木工程学院,河南郑州450001

出　　处：《世界桥梁》2015年第6期51-57,共7页World Bridges

摘　　要：针对预应力混凝土桥因耐久性或承载能力无法达到要求而寿命终结,为对其耐久性和安全性进行有效评估,基于抗力衰减和可靠度理论建立预应力混凝土桥使用寿命预测方法。该方法考虑混凝土碳化、钢筋锈蚀、预应力损失和荷载效应等因素,依据设计规范,以临界可靠指标的形式给出预应力混凝土桥碳化寿命、锈胀开裂寿命和承载能力寿命终结的判定标准,得出碳化寿命、锈胀开裂寿命和抗弯承载能力寿命的极限状态方程,对桥梁的使用寿命进行预测。采用该方法对某新建预应力混凝土梁桥的碳化寿命、锈胀开裂寿命和承载能力寿命进行预测。理论研究和应用结果表明,在一般大气环境及正常养护和运营条件下,该桥耐久性和承载能力在设计基准期内满足要求,并根据预测结果给出运营过程中检测周期的建议;该方法可有效评估预应力混凝土桥使用寿命。The prestressed concrete bridge would be deficient due to the insufficient durability or scarce load bearing capacity.To effectively evaluate its durability and safety,a service life evaluating method based on resistance attenuation and probability theory for prestressed concrete bridge is put forward,in which the factors,like concrete carbonization,reinforcement corrosion,prestress loss and load effect are counted.The judging criteria for the concrete carbonization life,corrosion expansion cracking life and expiration of load bearing life of a prestressed concrete bridge are given by way of critical probability index,and the ultimate state equations of carbonization life,corrosion expansion cracking life and anti-bending load bearing life are gained.The method has been used to the evaluation of the carbonization life,corrosion expansion cracking life and load bearing life of a newly-built prestressed concrete bridge.The results of the study and application demonstrate that in the common atmospheric environment and under normal maintenance and operation condition,the durability and load bearing capacity of the bridge in the design reference period meet the requirements,the inspection schedule during the operation process is proposed according to the results.This method can effectively evaluate the service life of the prestressed concrete bridge.

关 键 词：预应力混凝土桥 抗力衰减 可靠度理论 混凝土碳化寿命 钢筋锈胀开裂寿命 承载能力寿命 

分 类 号：U446[建筑科学—桥梁与隧道工程]