基于混凝土碳化与有限元的渡槽时变可靠度分析  

Time-dependent reliability analysis of aqueduct based on concrete carbonization and finite element

作　　者：张龙文 刘倩[1] 侯杰 ZHANG Longwen;LIU Qian;HOU Jie(College of Water Resources&Civil Engineering,Hunan Agricultural University,Changsha 410128,China;Key Laboratory of Agricultural Efficient Water Conservation and Digital Construction of Water Resources of Universities in Hunan Province,Changsha 410128,China;Precision Control Irrigation Engineering Technology Research Center of Hunan Province,Changsha 410128,China)

机构地区：[1]湖南农业大学水利与土木工程学院,湖南长沙410128 [2]农业高效节水与水利数字建造湖南省普通高等学校重点实验室,湖南长沙410128 [3]湖南省灌区精准控灌工程技术研究中心,湖南长沙410128

出　　处：《中南大学学报（自然科学版）》2024年第10期3972-3981,共10页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51738001);湖南省自然科学基金资助项目(2022JJ40188);长沙市自然科学基金资助项目(kq2202234);湖南省教育厅科学研究重点项目(23A0176,21A0123);2022年湖南省研究生科研创新项目(CX20220684)。

摘　　要：提出一种基于有限元的渡槽碳化时变可靠度分析方法。首先,利用Midas Civil软件建立钢筋混凝土渡槽的三维有限元模型,结合混凝土碳化深度预测模型构建渡槽时变功能函数。接着,将点估计法与结构有限元分析相结合,求解考虑混凝土碳化功能函数随机变量的前4阶矩。然后,通过双幂变换和JarqueBera检验,将原有功能函数转化为近似正态分布,采用高阶无迹变换(HUT)估计转化后功能函数的前4阶矩,进而计算混凝土碳化的渡槽时变可靠指标。最后,将计算所得时变可靠指标结果与4阶矩法和Monte Carlo模拟(MCS)结果进行比较分析。研究结果表明:本文提出的方法能够有效解决4阶矩法在高可靠指标计算时误差较大的问题,并且与MCS结果相比,本文所提方法具有效率高、精度高等特点。A time-dependent reliability analysis method for aqueduct carbonation based on finite element analysis was proposed.Firstly,a three-dimensional finite element model of a reinforced concrete aqueduct was established using Midas Civil software,and a time-dependent performance function was constructed considering the concrete carbonation depth prediction model.Then,the point estimation method was combined with structural finite element analysis to solve the first four moments of the random variables of the concrete carbonation performance function.The original performance function was transformed into an approximate normal distribution through dual power transformation and Jarque-Bera test.Subsequently,the high-order unscented transformation(HUT)was used to estimate the first four moments of the transformed performance function,and thereby the time-dependent reliability index of the aqueduct carbonation was calculated.Finally,the results of time-dependent reliability index were compared with those obtained by the four-moment method and Monte Carlo simulation(MCS).The results show that the proposed method can effectively solve the problem of large errors in large reliability indices calculations of the fourth moment method.Compared with the MCS results,the proposed method has high efficiency and accuracy.

关 键 词：有限元法 渡槽 时变可靠度 双幂变换 HUT 

分 类 号：TV311[水利工程—水工结构工程]