【摘要】 本文详细介绍了一跨度33m的钢-混凝土组合空腹楼盖的结构形式。采用基于壳单元和空间梁单元的混合有限元模型对其进行了理论分析,得到了结构的位移、内力、自由振动的振型及频率。介绍了结构各构件及支座节点的设计、结构的施工方法和流程。为验证理论分析的可靠性,对该组合空腹楼盖结构进行了原位试验,测试了结构自由振动的基本频率,并与理论计算值进行了比较和分析。研究表明,组合空腹楼盖的下层钢肋处于拉-弯、上层混凝土板处于压-弯的受力状态,从支座到跨中,其轴力逐渐增大而弯矩逐渐减小,因此,组合空腹楼盖的应力分布比较均匀,可以充分发挥材料的强度,有效地节省材料;剪力键主要承受弯矩和剪力,从支座到跨中,其弯矩和剪力逐渐减小。设计荷载下,结构最大挠度110mm;结构的前10阶振型均为竖向振型,振动规律类似于实体平板;基本频率的理论计算值与实测值分别为3.15Hz和5.0Hz,分析了误差存在的原因,进而说明了理论分析的可靠性。更多还原

【Abstract】 This paper introduces in detail the structural form of a steel-concrete composite open-web plate whose span is 33m.For theoretical analysis of the structure,the combination finite element method of beam elements and shell elements model is adopted,and the displacement,internal force,vibration shape and frequency of natural vibration are obtained.This paper also introduces design of each component and support node of the structure,construction method and technological process.To verify the reliability of the theoretical analysis,field test of the basic frequency of natural vibration of the structure is conducted.Results show that the lower steel rib of composite open-web plate is in pull-bending,upper concrete plate is in press-bending,and its moment decreases and axial force increases from support to mid-span.Therefore,the internal force of the composite open-web plate distributs uniformly and its strength of materials develops effectively.The shear keys bear moment and shear and decrease from support to mid-span.Under design load,the largest deflection is 110mm.The first ten natural vibration modes of the structure are vertical modes and the vibration law is similar to that of solid plate.The basic frequency of the theoretical value is 3.15Hz and measured value is 5.0Hz.The reasons of the existence of tolerances are analyzed to describe the reliability of the theoretical analysis.更多还原