基于可靠度的锈蚀钢筋混凝土结构使用寿命预测

在役结构能否继续安全使用已成为结构工程师和管理决策者日益关心的重要问题.针对一般大气环境下的锈蚀钢筋混凝土结构,提出了基于结构性能的使用寿命预测模型.该模型包括4个阶段,即钢筋开始锈蚀阶段、混凝土锈胀开裂阶段、构件适用性达到容许程度所经历的阶段以及构件承载力达到最小可接受程度所经历的阶段.根据实测的结构响应,采用可靠度方法确定了在役结构使用寿命的每个时段.该方法可用于在役钢筋混凝土结构剩余使用寿命评估及其维修加固决策.

Reliability-based service life prediction of steel-corroded concrete structures

The possibility of safely extending the service life of the existing structures is a problem that has become more and more important for the structural engineers and asset managers. A performance-based model for service life prediction of the steel-corroded concrete structures located in an atmospheric environment is presented. In this model, the life cycle of in-service concrete structures consists of four phases of lifetime, e.g. , the time periods from the completion of a newly-built structure to corrosion initiation in the structure, from the initiation of corrosion to corrosion-induced concrete cracking, from the concrete cracking to acceptable longitudinal crack width, and from loss in serviceability to acceptable ultimate limit state. Based on the structural response measured by strength and serviceability, reliability approaches were employed to determine the time period for each phase of service life. The method presented can be used to assess residual life of the existing structures in an atmospheric environment and make decisions with regard to its maintenance and strengthening for structural engineers and asset managers.