在役钢筋混凝土结构承载力寿命分析

Analysis on the bearing capability life of existing reinforced concrete structures

在役钢筋混凝土结构使用寿命的终结其原因是多方面的,因结构性能退化导致结构达到承载力极限状态致使结构破坏是实际工程中最为常见的破坏形式.由于结构所处使用环境的随机性和材料性能的不确定性,使得结构使用寿命具有随机性.运用可靠度理论,考虑结构抗力的衰减,采用结构不同安全等级的允许可靠指标作为结构承载力失效标准,建立基于全随机过程的可靠度模型,提出了在役钢筋混凝土结构构件的承载力剩余使用寿命的计算方法,并通过算例验证了该寿命计算方法的工程实用性,阐述了在实际工程中进行寿命计算的具体方法和步骤.

There are many reasons which may affect the residual life of existing reinforced concrete structures. The bearing capacity limit state resulted from the recession of structural performance is the main reason of the failure of structures. Due to the randomicity of environment and uncertainty of material property, the residual life of structure becomes stochastic. Using reliability theory and considering the attenuation of structural resistance, the authors use the permitted reliability index for different degree of structures as standard of bearing capability failure and establish the full stochastic process reliability model. The calculated method and its steps of residual life under the bearing capability state of existing reinforced concrete structures are proposed. The instance shows this method in engineering is practical.