分布式连接全装配RC楼盖平面内受力特性与结构地震响应机理研究

Discrete connected new-type precast RC diaphragm (DCNPD) is a kind of un-topped precast RC structure, and has been becoming immediate area of research focus in construction industry, as it possessing the advantages of good structure quality, high production efficiency, less resource consumption and environmental pollution. Whereas the in-plane mechanism of DCNPD and the seismic response of structures adopting DCNPD are remain unrevealed at present, it’s has an important theoretical significance and engineering practical value to carry out this project research.. DCNPD hybrid slab joint experiments will be conducted on the self-developed equipment to reveal its’ mechanical mechanism under combined tension (compression) and shear force. The restoring force model of DCNPD slab joint under combined stress and cyclic loading will be built by experimental fitting method. And then, the restoring force model will be developed in the finite element model (FEM) program, to build the two-dimensional (2D) refined FEM for diaphragm nonlinear static pushover analysis(NSPA) and three-dimensional (3D) refined FEM for DCNPD building structure nonlinear transient dynamic analysis(NLTDA)，also as known as nonlinear time history analysis. And these 2D NSPA and 3D NLTDA models will be verified and corrected, by simulations of typical tests. The DCNPD in-plane mechanism in slab transversal arrangement direction will be revealed by in-plane experimental tests and 2D NSPAs, and the in-plane stiffness calculation method of DCNPD will be proposed on the basis of equivalent beam theory and energy variation principle. DCNPD in-plane stiffness is a quite complex question but of prime importance for the establishment of the simplified theoretical analysis model of structures adopting DCNPD. The dynamic property and seismic response mechanism of DCNPD structures will be revealed by large scale shaking table tests and 3D NLTDAs. And in the last, the simplified theoretical analysis model of structures adopting DCNPD will be established and seismic design method will be proposed from the aforementioned studies.. The research achievements will consummate the theory and basic data for buildings adopting DCNPD, and has important scientific significance in promoting the study and application of building structures with similar diaphragm mechanical property.

DCNPD为干式连接楼盖体系，具有结构质量好、生产效率高和环境污染小等特点，已成为建筑工程领域研究热点，但楼盖平面内受力机理和结构地震响应机理尚未明确，因此，开展本课题研究具有重要的理论意义和工程实用价值。.本项目通过DCNPD混合式板缝节点受力性能试验，揭示其拉（压）剪复合受力机理；采用试验拟合法，建立板缝节点在复合应力下的恢复力模型；然后将该恢复力模型开发到通用有限元程序，建立楼盖2D和结构3D数值模型，并由典型试验对模型进行修正；基于DCNPD平面内试验和2D数值模拟，揭示楼盖平面内受力机理，采用等效梁理论和能量变分原理等建立DCNPD平面内刚度计算方法；基于大尺寸振动台试验和3D数值模拟，揭示NCNPD结构地震响应规律，建立考虑楼盖平面内实际刚度的结构抗震分析模型，提出结构抗震设计方法。.研究成果将丰富DCNPD建筑结构分析与设计理论，为该类建筑结构的研究和应用提供试验和理论依据。

本项目针分布式连接全装配RC楼盖（DCPCD）平面内受力特性与结构地震响应机理进行了系统研究。. 首先，在板缝节点层面上，研究了DCPCD板缝节点受力性能。进行了5种共18个板缝节点在平面内水平单调荷载、低周反复荷载和拉剪复合作用下的足尺模型试验，研究了板缝节点的承载能力、破坏形态、滞回曲线、延性、耗能和拉剪复合受力性能等。基于剪摩擦理论和拉压杆模型理论提出了节点承载力和刚度简化计算，并基于试验拟合法建立了板缝节点在单向和复合作用下的恢复力模型。. 其次，在楼盖构件层面上，研究了DCPCD平面内受力机理。进行了DCPCD在平面内反复荷载作用下的拟静力试验，研究了楼盖的破坏形态、面内变形特征、滞回特性、延性、刚度和耗能能力等，试验结果表明梁-板连接件和板缝连接件传力性能良好，DCPCD具有较好的整体和较大的平面内刚度；DCPCD具有一定的延性，但耗能能力不佳，验证了采用基于弹性楼盖的抗震设计方法的必要性；基于板缝连接件拉压刚度不等、预制板实际荷载反应等改进的等效梁模型理论提出了DCPCD平面内刚度计算方法；基于板缝节点和楼盖试验，开发了节点连接单元模型和动态本构模型，构建了DCPCD精细化数值分析模型。. 最后，在结构层面上，研究了DCPCD的建筑结构动力特性与地震响应规律。进行了DCPCD建筑结构动力弹性与弹塑性时程分析，研究了DCNPD地震响应规律，并与同尺寸现浇结构模型进行对比，分析其响应差异和结构受力关键部位等。设计制作了一栋4层2开间单跨DCPCD框架-剪力墙结构1/4缩尺模型，并通过不同水准地震工况的振动台试验，研究了结构的模态特征、破坏形态、加速度与位移响应、楼盖平面内变形规律与楼盖平面内刚性特征等。构建了DCNPD建筑结构抗震分析简化空间计算模型，研究了建筑平面布局、结构布置、结构刚度比等对结构位移、楼层加速度和楼盖平面内变形等影响规律；基于上述3类分析结果，完善了DCPCD和采用DCPCD的多高层建筑结构抗震设计方法。. 研究结果可为全装配式RC楼盖建筑结构的研究和应用提供参考和依据。