大跨度装配整体式钢-混凝土叠合板组合楼盖力学机理研究

In order to promote the building Construction industrialization and residence industrialization, the development of assembly building is imperative, but the research of the floor system is not mature. The assembly monolithic steel-concrete composite floor system with precast slabs has good development and application prospect in the large-span assembly structure with the advantages of good overall performance, high bearing capacity, high stiffness and convenient construction. A new type of composite floor system will be studied，in which ultra-high performance concrete, high strength steel reinforcement and appropriate connection will be used in order to reduce the height of floor section, improve the floor strength, stiffness and seismic performance. The problem of concrete cracking in the negative moment region of large-span composite floor system will be solved through the use of a new type of uplift-restricted and slip permitted connection. The flexural behavior of the composite floor system will be studied, and the design calculation method considering the secondary force and local-released combined action will be proposed according to the ultimate state of bearing capacity and serviceability limit state. The seismic behavior of large-span fixed edge composite floor system will be studied, the spatial combination effect of fixed edge composite floor system will be revealed, and the seismic design method considering the spatial combination effect of fixed edge composite floor system will be proposed. The research results can provide reference for the engineering application of large span assembled monolithic steel-concrete composite floor system with precast slabs.

为促进建筑工业化和住宅产业化，装配式建筑的发展势在必行，但是相配套的楼盖体系的研究还尚不成熟。装配整体式钢-混凝土叠合板组合楼盖具有整体性能好、承载力高、刚度大、施工方便等优点，在大跨度装配式结构中有很好的发展和应用前景。本项目拟研究新型大跨度叠合板组合楼盖，通过超高性能混凝土、高强钢筋的使用、连接件的合理设置，以实现降低楼盖高度，减少楼盖自重，提高楼盖强度、刚度和抗震性能的目的；通过新型抗拔不抗剪连接件的使用，以解决大跨度叠合板组合楼盖负弯矩区混凝土开裂问题；研究大跨度叠合板组合楼盖的受弯性能，针对承载力极限状态和正常使用极限状态，提出考虑二次受力效应和局部释放组合作用的设计计算方法；研究大跨度固接叠合板组合楼盖框架体系的抗震性能，揭示固接叠合板组合楼盖框架体系的空间组合效应，提出考虑楼盖空间组合效应的抗震设计方法。研究成果可为大跨度装配整体式钢-混凝土叠合板组合楼盖的工程应用提供参考。

针对大跨装配式结构缺乏配套楼盖体系研究的问题，本项目提出了一种适应于大跨结构的板端开槽孔SPD预应力空心板叠合组合楼盖，并对其抗弯性能进行了试验研究和数值分析。研究结果表明：叠合层可以增加楼盖的整体性，提高板缝的传力能力，协调相邻SPD板间的垂直变形，当叠合层厚度较大时可适当增加叠合面的抗剪强度；1.5:1长宽比楼盖较1.25:1和1:1长宽比楼盖整体性和延性更好，更接近整浇双向板楼盖，SPD板应用于装配式双向板楼盖中是可行的；楼盖整体性能很好，最终以冲切破坏和受弯破坏为主，未发生剪切破坏；适当增加叠合层厚度可以显著提升楼盖的承载力、开裂荷载、初始刚度，但提高叠合层配筋率对楼盖无明显增益；板缝形式不影响楼盖的开裂荷载、初始刚度、承载力和纵向传力，拼接板缝更为经济高效；梁-板连接处钢筋不影响楼盖承载力，可适当减少配筋量、优化布置形式；板缝只有在板端处受力比较严峻，可以适当减少纵向配筋量或只在板缝端部进行配筋。最后提出了SPD预应力空心板叠合组合楼盖的承载力设计计算方法。为解决大跨度楼盖负弯矩区抗裂问题，本项目提出在楼盖中采用新型大滑移量开孔钢板抗拔不抗剪连接件和纤维抗裂高性能混凝土现浇层，并对采用此种抗裂措施的叠合板组合楼盖进行了抗震试验和精细化有限元分析。研究结果表明，在负弯矩区采用钢板抗拔不抗剪连接件和高性能混凝土可以提高楼盖的开裂荷载，减少裂缝宽度，提高结构的耗能能力；采用抗拔不抗剪连接件时，抗拔不抗剪区域的长度对开裂荷载和开裂位移有明显影响，对开裂位置也有一定的影响；现浇层的设计参数中，混凝土抗拉强度的影响最大，纵筋配筋率也有一定的影响，纵筋强度几乎无影响；预制板的设计参数对结构的开裂荷载和开裂位移影响均不大。最后提出了此种楼盖的承载力简化计算方法。本项目研究成果可以为大跨装配式组合楼盖的工程应用提供参考。