钢-混凝土叠合板组合桥面的徐变和应力重分布研究

以某特大跨度拱桥的钢-混凝土叠合板组合桥面为工程背景进行有限元分析,探讨了活载和恒载作用下不同龄期混凝土弹性模量的取值;研究了预制板不同加载龄期、混凝土板是否采用叠合板等因素对大跨度钢-混凝土叠合板组合结构徐变的影响,以及钢-混凝土叠合板组合梁截面由于徐变引起的内力重分布效应。研究结果表明:钢-混凝土叠合板组合结构中,由于预制混凝土板和现浇混凝土龄期不同,从而收缩徐变和变形模量不同,在运营过程中,会引起现浇混凝土、预制混凝土板和钢梁三者之间发生应力重分布。与全部一次现浇混凝土组合梁相比,采用叠合板梁可以减少混凝土的收缩徐变。

Creep and stresses redistribution on steel-concrete composite structure with combined slab of long span bridge

The 3D finite element analysis of a steel-concrete composite deck system with combined slab of a long span arch bridge was calculated.The values of concrete modulus with different ages under the actions of live load and dead load were discussed.The influences on creep of long span steel-concrete composite structure with combined slab produced by complications were adopted in concrete slabs were considered.Stresses redistribution produced by creep on the section of steel-concrete composite beam with combined slab were studied.The results show that shrinkage,creep and compression modulus of cast-in-place concrete and precast concrete slab in steel-concrete composite structure with combined slab are different because the ages of them are different.It can produce stresses redistribution among cast-in-place concrete and precast concrete slab in usage.Using composite beam with combined slab can decrease creep and shrinkage of concrete compared with using in-situ concrete composite beam.