预应力混凝土变截面箱梁桥底板预应力束的等效径向力研究  

Study on equivalent radial force in prestressed cable of the prestressed concrete variable cross-section box girder bridges

作　　者：钟新谷[1] 林小雄[1] 舒小娟[1] 

机构地区：[1]湖南科技大学,湖南湘潭411021

出　　处：《土木工程学报》2013年第4期103-109,共7页China Civil Engineering Journal

基　　金：国家自然科学基金(51178183)

摘　　要：预应力变截面混凝土箱梁桥底板崩裂主要是由底板预应力束的等效径向力引起的。以箱梁底板预应力束的等效径向力经典计算公式为基础,分析影响等效径向力的敏感性因素,推导定位误差和折线拟合曲线这两种因素对径向力的影响,修正经典等效径向力的计算公式,同时进行在建桥梁底板预应力束的径向应力的测试,表明提出的修正公式计算的径向应力与实测应力基本吻合,为变截面混凝土箱梁底板防崩裂设计提供了理论与实测依据。The bottom slab cracks are mainly caused by the equivalent radial forces in the prestressed variable crosssection concrete box girder bridges. Based on the classic formula of equivalent radial force, the sensitivity factor of the equivalent radial force is analyzed, the influence coefficient on the positioning error and polyline fitting curve is deduced, and the classic formula of the radial force is revised. The tested radial stresses of the bottom slab in the constructing bridge show that the the radial stresses calculated by the amended formula agree well with the testing radial ones. This paper provides a measured and theoretical principle for crack design in the prestressed variable cross-section concrete box girder bridges.

关 键 词：混凝土变截面箱梁桥 预应力束 径向力 抗崩钢筋 

分 类 号：U448.213[建筑科学—桥梁与隧道工程]