既有预应力混凝土桥梁结构承载能力时变可靠度研究

Time-dependent reliability analysis of flexural capacity of existing prestressed concrete bridges

文章在研究了既有预应力混凝土桥梁抗力和荷载时变特性的基础上,建立了现有预应力混凝土桥梁抗弯承载能力的时变可靠度计算模型,讨论了结构时变可靠度的计算方法,编制了可靠度计算实用分析程序,计算了时变可靠度指标,以我国高速公路桥梁中广泛应用的多座预应力混凝土T梁桥为例,在考虑其抗力时变特性的理论基础上,研究承载能力可靠度的衰减规律。

In this paper,based on the study of the stress and load time-dependent characteristics of the existing prestressed concrete bridges,a probabilistic model of resistance for the strength limit state for flexural capacity is established,the time-dependent reliability analysis methods are discussed,the program composition with C++is made to calculate the time-dependent reliability index of flexural capacity.Based on the time-dependent characteristics of existing prestressed concrete bridges and the analysis of the deficiency of time-dependent reliability index,a number of prestressed concrete T-girder bridges,which are widely used in highway bridges in China,are presented to study the attenuation law of the bearing capacity reliability.