【作者】 曾应祝；

【导师】 赵人达；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2011， 硕士

【摘要】 钢桁架—混凝土结合梁是混凝土桥面板与钢桁架共同受力的一种新型组合结构,因其刚度大、建筑高度低、整体性好、噪音小和行车动力性能好等优越性能,已在欧美、日本等国家的高速铁路中得到了广泛应用,随着我国既有线提速和高铁的大力建设,该类桥型必将得到越来越广泛的应用。因此,本文开展钢桁架—混凝土结合梁受力性能的研究,具有重要的现实意义。本文介绍了钢桁架—混凝土结合梁在国内外的应用和研究现状,并介绍了与其相关的钢桁架图式及特点、剪力连接件的种类和栓钉承载力的计算方法、混凝土桥面板与钢桁架纵横梁不同结合类型与特点。为了研究下承式密布横梁体系简支钢桁架—混凝土结合梁的受力性能,利用空间有限元计算分析了一座拟建的108m跨度该类型桥梁,主要内容如下：1、研究了结构在一期恒载、二期恒载和双线对称活载作用下结构的受力性能、下弦杆与桥面系轴力的分配情况、混凝土桥面板的应力分布情况,考察了结构的自振特性；2、研究了结构在单线偏载作用下加载侧与非加载侧主桁架下弦杆的位移情况、横梁两端剪力的分配情况、主钢桁架的扭转情况；3、考察了分别反映骤然降温、日照影响、温度梯度三种温度荷载作用下结构的受力情况和混凝土桥面板的应力分布情况；4、剪力连接程度和横梁刚度对钢桁架—混凝土结合梁的受力情况有较大影响,本文对双线对称线荷载作用下不同剪力连接程度和横梁刚度对钢桁架下弦杆位移、内力的影响和混凝土桥面板受力情况、应力分布的影响做了一些分析。本文得出的一些结论可为铁路钢桁架—混凝土结合梁桥的设计提供参考。更多还原

【Abstract】 The steel truss-concrete composite beam is a new kind of composite structure, in which the concrete deck slab and the steel co-act togther, has come into widly use in high-speed railway by European, American countries and Japan because it has so many advantages such as big stiffness, low building height, good integrity, slight noises and well dynamic behavior in train driving. Along with the speed up of the existing railway and the rapid construction of high-speed railway this type bridge must be widly used in China too So this thesis propsoses to study the structural behavior of steel truss-concrete composite beam, it is significant.This thesis introduces the application and current research of the steel truss-concrete composite beam at home and abroad, steel truss form and characteristics, type of shear connectors and bearing capacity calculation method of the stud, the different combing condition of concrete slab with stringer and floorbeam of steel truss.In order to study the structural behavior of the through multi-crossbeam floor system simply-supported steel truss-concrete beam, the author uses of spare finite element calculation analysis for a proposed 108m span. The main contents are follows:1. Reasearch the structural behavior of the structure, the axial force distribution between the lower boom and the deck, the stress distribution of concrete bridge panel under the lst-stage dead load,2nd-stage dead load and live load including double-track symmetry live loads,and the natural vibration characteristics of the structure.2. Reasearch the displacement condition of the load side and unload side lower boom, the shear distribution between the two nodes of the floorbeam, the torsion of the main steel truss under the single-track live load.3. Reasearch the load structure stress condition and its distribution of the concrete bridge deck under three different temperature load which can reflect the condition of sudden cooling, sunshine influence and temperature gradient.4. The degree of shear connection and the stiffness of floorbeam have great effect on the stress of the steel truss-concrete composite beam, this thesis also made some study on lower boom displacement of the steel truss, internal forces and the stress distribution of concrete bridge deck under double-track symmetry live loads with different degree of shear connection and stiffness of floorbeam.The results may be taken as reference for the design of steel truss-concrete composite beam.更多还原