钢衬钢筋混凝土管道裂缝控制标准可靠度分析

针对水电站钢衬钢筋混凝土压力管道裂缝控制标准可靠度研究尚不充分的情况,将蒙特卡洛法与董哲仁法裂缝宽度计算公式相结合,建立了一种新的可靠度计算方法。结合工程实例及模型试验参数,对我国现行钢衬钢筋混凝土压力管道裂缝控制标准的可靠度指标进行了计算,并分析了主要的影响因素。研究表明:目前我国钢衬钢筋混凝土压力管道裂缝控制标准的安全度设置水平整体略低,但处于允许范围内;裂缝宽度限值、保护层厚度以及有效配筋率等对裂缝控制标准的可靠度水平影响均较为显著。

Reliability analysis of crack control standard for steel lined reinforced concrete penstocks

In view of the insufficient research on crack control standard of steel lined reinforced concrete penstocks in hydropower project, a new reliability calculation method is established based on the combination of Monte Carlo method and crack width calculation formula provided in Dong Zhe-ren method. According to the parameters from practical engineer examples and model tests, the reliability indexes of present crack control standard for steel reinforced concrete penstocks in corresponding Chinese codes are calculated, and the main influential factors are analyzed. Finally it is found that the present reliability level of crack control for steel lined reinforced concrete penstocks is a little lower, but still in an allowable range. Meanwhile the crack width limit, protection layer thickness and the effective reinforcement ratio have significant influence on the reliability level of crack control standards.