【作者】 张道明；

【导师】 梁力；

【作者基本信息】 东北大学 ， 工程力学， 2008， 博士

【摘要】 预应力外包钢-混凝土组合梁是在外包钢-混凝土组合梁的基础上发展起来的一种新型外包钢组合梁,具有用钢量省、稳定性好、刚度大、承载力高、截面开裂弯矩高、弹性工作范围大和能充分利用组合材料力学性能等优点,对其进行研究具有重要的理论意义和实用价值。本文通过模型试验和理论分析了预应力外包钢-混凝土组合简支和连续梁的抗弯受力性能。通过对三根2m长的预应力外包钢钢筋混凝土组合简支梁和两根6m长预应力外包钢钢筋混凝土组合连续梁的静载载荷试验和有限元数值仿真分析及理论分析,深入地探讨了预应力外包钢钢筋混凝土组合梁在预应力及各级荷载作用下抗弯力学性能。在试验中,实测了试件在预应力及各级荷载作用下控制截面的应变、裂缝宽度、挠度、承载力和各组合材料的力学性质,分析了其抗弯承载特性,为其有限元数值仿真模拟和理论研究奠定了物质基础。在预应力筋与构件耦合相互作用方面,通过对预应力对结构作用机理的研究,提出了直接内载法计算预应力内荷载；根据内荷载的特点,给出了预应力摩擦应力损失方程,证明了预应力内荷载的自平衡性,说明了等效荷载法是直接内在法的特例,确定结构在预应力作用下的主内力解析表达式,并根据曲线预应力筋线型特点,提出应用三次样条插值函数为预应力筋线型函数；根据预应力外包钢组合梁的工作特点,建立了预应力外包钢钢筋混凝土组合梁有限元数值仿真分析模型,进行了静荷载作用下结构抗弯全过程仿真分析；在有限元模型建立过程中,提出应用层状界面单元模拟外包钢板与钢筋混凝土梁之间的粘结滑移力学行为,并确定了层状界面单元等效节点刚度,实现了利用ANSYSY有限元程序模拟分析外包钢板与混凝土之间的粘结滑移；在有限元分析过程中,依据直接内载法,把预应力内荷载直接施加在结构上,分析了预应力与结构的相互作用；其数值结果和实测结果具有一致性。根据外包钢组合梁微单元截面内力平衡,建立了分离式外包钢板和钢筋混凝土梁粘结滑移理论分析模型,确定了外包钢板与钢筋混凝土梁年节滑移方程。理论计算结果与实测及数值结果基本一致。依据实测和数值分析结果,采用变形协调原理和试算法,给出了其粘结滑移的解析方程和其抗弯承载各阶段截面抗弯解析方程,其结果和实测及数值结果基本吻合,说明了理论分析的可靠性。更多还原

【Abstract】 The prestressed outer-plated steel-concrete composite beam is a new type of outer-plated steel-concrete composite beam, which developed from the outer-plated steel-concrete composite beam, and possesses with the merits of steel-saving, good stability, large rigidity, increase crack moments at section, enlarge range of spring work, a high load-bearing capacity and plenty of utilizing mechanical performance of composite materials. The study on the prestressed outer-plated steel-concrete composite beam is important significance in both theory and application. Based on the models test numerical computation and theoretical analysis, the resistance to bending of the prestressed outer-plated steel-concrete composite beams are presented. The completion main works and obtained achievements include:Based on the tests of static loads for tree prestressed outer-plated steel-concrete composite simple beams which are 2 meters length, and two prestressed outer-steel-plate-concrete composite continuous beams which are 6 meters length, the resistance of bending of outer-plated steel-concrete composite beams are researched. In test, the strain of cntroled beams section, the crack widths of concrete, the deflections of midspan, the benring capacity of composite beams and the mechanical performances of composite material in all levels load are studied.According to the mechanism of interaction between tendons and structure, the direct inter load method is proposed to calculate prestressed internal load. Based on the theory of the direct inter load method, self-balance of prestressed internal load is proved and the analytic equations of the main internal force in prestressed internal load are given. For the curve profile of tendons, the cubic spline functions are used to describe tendons profile.According to the feature of prestressed outer-plated steel-concrete composite beams, the separate model of finite element is used. In the finite element model, the layered interface elements is proposed and elements matrix are derived to simulate slip mechanical behavior between steel plate and concrete. Based on the comparison between the results of finite element and the tested results, the finite element analysis can show mechanical behavior of composite materials in prestressed outer-plated steel-concrete composite beams under loads, and the data collected from experiments are close to. the results from the numerical simulation.Based on the tested and numerical results and the micro-elements balance of the internal force, the sliping equation of outer-plated steel-concrete composite beams are presented under various loads, and the data collected from experiments and numerical simulation are consistency to the theoretical results;According to tested and numerical results, the methods of compatibility of deformation and the method of trying calculation to slove the equation of bending resistance in various steps of load-bearing are proposed. By the comparison with theoretical, numerical and tested results, the reliability of theoretical analysis abort prestressed outer-plated steel-composite beam are shown.更多还原