【作者】 刘运林；

【导师】 叶献国；

【作者基本信息】 合肥工业大学 ， 结构工程， 2014， 博士

【摘要】 为适应国家十二五规划及未来对住宅产业化发展的需求,对在装配式结构中占比重较大的钢筋混凝土叠合楼板开展研究。现有叠合楼板主要是单向受力形式,拼缝处受力性能较弱,综合造价较高,这些都降低了叠合楼板的推广速度,影响住宅产业进程。国内外专家学者对叠合底板形式和双向叠合楼板板拼缝处理做了一些研究,并提出一些新的叠合底板形式和拼缝处理构造,但都存在一定的局限性,课题组从拼缝处的受力机理来研究叠合楼板的拼缝处承载能力,考虑施工易操作性,通过构造来解决叠合楼板的拼缝传力问题。文中首先研究了叠合楼板叠合面的抗剪和抗拉粘结性能,分析了拼缝处截面受力状态、拼缝处钢筋锚固受力状态和叠合面的受弯状态；分析了常用的格构钢筋对叠合楼板的刚度和承载的影响,采用子结构理论建立刚度计算公式；对现有的粘结滑移曲线进行比较分析,在此基础上,提出改进的粘结滑移曲线,并用数值模拟进行验证；通过12块叠合楼板的试验和有限元数值模拟,研究不同拼缝连接形式叠合板的受力性能；文中最后提出了一种新型增强拼缝连接形式,并用试验验证了其受力性能。论文研究的主要成果如下：(1)通过对叠合结构叠合面抗剪、抗拉试验统计分析发现,当混凝土强度大于C20时,叠合面试验抗剪强度与混凝土立方体抗压强度表现出了较强的相关性,回归方程显著；对叠合面抗拉强度与后浇混凝土的轴拉强度表现出较强的相关性,回归结果可信度较高。(2)推导出了拼缝处钢筋锚固承载力受叠合面影响系数,通过分析得出对于设置格构钢筋的叠合楼板,拼缝处可以满足受拉钢筋锚固要求；从叠合楼板拼缝处叠合面受弯状态推导出带拼缝叠合楼板的叠合面破坏时极限弯矩。(3)通过我国规范的短期刚度计算公式的推导过程,分析了应用于板的刚度计算时存在的局限性；对比分析了不同刚度计算公式,得出了一些有益的结论；采用子结构理论,对格构钢筋进行了刚度等效,推导出等效计算公式,以便分析格构钢筋对叠合板的刚度贡献。(4)提出了改进的粘结滑移曲线本构模型,并进行了数值模拟,模拟曲线和试验曲线符合较好,验证了模型的可靠性。(5)通过12块叠合楼板的试验和有限元分析结果表明：对拼缝处未设附加约束的叠合楼板具有一定的承载能力,但搭接纵筋超过屈服荷载后,会产生脆性断裂破坏；当设置格构钢筋约束时,无论是端拼缝和侧拼缝(格构钢筋横向设置和竖向设置),都能够保证拼缝处钢筋的有效传力,实现“等承载力连接”。(6)数值计算结果和试验结果吻合较好,表明文中的数值模拟方法的可靠性；数值分析结果表明,模型中添加粘结弹簧单元对承载力和刚度影响不大,但对于裂缝开展有很明显的影响。(7)文中提出了一种新型增强型整体式拼缝连接形式,试验研究结果表明：采用该种连接形式的叠合板在拼缝处刚度得到加强,受弯承载力得到不同程度地提高,拼缝处最大应力得到转移,裂缝较迟出现,可以实现拼缝处的等同现浇。更多还原

【Abstract】 In order to meet China’s12th Five-Year Plan and the future development of the housing industry needs, we launch researching on the superimposed slab which contributes a large proportion to fabricated structure. The existing superimposed slab parts only were used as one-way slabs and have weak performance joints, so they can not release the vast bearing capacity, and then cause increasing the cost which brings about slowing down the march of housing Industrialization。Domestic and foreign experts and scholars have done some research on the prefab element and the joint of bidirectional superimposed slab and got some achievements which have some limitations. Research group will carry out research on the carrying force mechanism of superimposed slab in the joint, so as to solve the problem of unidirectional force transferring.Research group study on shear and tensile bond performance of the superimposed slabs, perform analysis of stress state of joints section and lapped reinforcement anchorage stress state and analysis of contribution to superimposed slab’s stiffness and bearing capacity especially in the joint by lattice girder. Using the sub structure theory to establish the stiffness formula; Carring on comparative analysis to the existing bond slip curve, on the basis of this, putting forward a new modified bond slip curve, then using numerical simulation to verify it; According the research results, we put forward some new constructional details and through carrying out tests and numerical simulation on some specimens to validate the theoretical model. Finally, we propose the design rule for applying to bidirectional superimposed slabs.(1) Statistical analysis found that, when the concrete strength is more than C20, laminated surface strength and concrete cube strength shows a strong correlation between shear test and has a significant regression equation; tensile strength of laminated surface tensile strength and post pouring concrete tensile strength also shows strong correlation.(2) Deduced formulas for calculating the moment in the ultimate bearing state; developed laminated surface effect coefficient of bearing capacity of anchor bar.(3) There are limitations to apply the stiffness formula of short-term for calculating stiffness of slab; comparing different stiffness calculation formula, some useful conclusions are obtained; based on the sub structure theory, deduced a equivalent stiffness calculating formula for the lattice girder.(4) Proposed a improved bond slip constitutive model, and verified the reliability of the model through the numerical simulation. (5)12pieces of superimposed slab tests and finite element analysis results indicate that: The superimposed floor slabs without additional constraints have a certain carrying capacity before occurring brittle fracture; the lattice girder restraint can ensure the effective force transformation high ductility, the bearing capacity of superimposed slabs depends on the bearing capacity of joints section.(6) The numerical results agree well with experimental results, which shows that the reliability of numerical simulation method in the paper; numerical analysis results show that the addition of spring element model is not big to the bearing capacity and stiffness influence, but has obvious effect on Crack propagation.(7) This paper proposes a new enhanced integral joint connection pattern for superimposed slab, test results show that:the connection form can strengthen the section stiffness in joint and increase bending capacity of the slab.更多还原