结构设计的不确定问题分析及在既有结构工程评定中的利用

Uncertainty analysis of structural design and utilization in the performance assessment for existing structures

在工程评定中应该对结构设计阶段的不确定性储备合理利用,以减少加固工程量。从分项系数设计方法、材料强度、计算模型、统计参数的变异性以及作用五个方面,对结构设计阶段的不确定问题进行分析,提出对既有结构工程评定中合理利用这些储备的原则。最后以一实际工程为例,在对结构构件承载力评定时考虑材料强度的不确定性储备。检测评定结果表明,构件承载力的安全水平均高于设计要求值,该混凝土结构安全可靠。

In the performance assessment for existing structures,uncertainty reserve in structure design has to be utilized rationally.It aims at decreasing the structural strengthening quantity.In the structural design,uncertainty refers to partial factor design method,material strength,calculation model,variability of statistical parameter and the action.Uncertainty analysis is made from the above aspects.And the assessment principles are summarized for utilizing the uncertainty reserve in structural design.Finally,taking a project as a case,uncertainty reserve of material strength is considered for member load-carrying capacity assessment.The results show that the value of the member load-carrying capacity is larger than its design value of strength.This structure is safe and reliable.