Random Field-Based Time-Dependent Reliability Analyses of a PSC Box-Girder Bridge

Applied Sciences

Zheheng Chen¹  Weiwei Lin²  Tong Guo³  Shaobo Liu⁴ 

[1] College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, China;Department of Civil Engineering, Aalto University, Rakentajanaukio 4 A, 02150 Espoo, Finland;Key Laboratory of Concrete and Prestressed Concrete Structures, Ministry of Education, Southeast University, Nanjing 210096, China;School of Architecture and Civil Engineering, Nanjing Institute of Technology, Nanjing 211167, China;

关键词: long-span box-girder bridge;    random field;    local average method;    important sampling;    creep and shrinkage;    time-dependent reliability;   

DOI  :  10.3390/app9204415

来源: DOAJ

【 摘 要 】

The parameters affecting structural reliability are usually regarded as independent random variables in the current reliability analyses of bridge structures while the randomness of these structural parameters in spatial distribution is neglected. To overcome this disadvantage, the random field model should be used to describe their probability distribution. In this paper, a structural reliability analysis method considering the effect of a random field is proposed, and its validity is verified by three numerical case studies. A prestressed concrete (PSC) box-girder bridge with a main span of 150 m is selected for demonstration, and the importance sampling (IS) method is applied to estimate its failure probability, in which the influences of shrinkage and creep, stress relaxation, and shear lag on the time-dependent performance of the structure are taken into account. In addition, the random fields of the structure are discretized by using the local average method (LAM). Finally, the effects of random field parameters, such as the number of discrete elements, correlation model, and correlation length, on the reliability of the box-girder bridge are discussed.

【 授权许可】

Unknown