超高性能混凝土叠合梁弯曲性能研究

发布时间：2018-02-22 05:41

本文关键词： 活性粉末混凝土组合构件弯曲性能收缩徐变界面剪应力　出处：《北京交通大学》2013年硕士论文　论文类型：学位论文

【摘要】：活性粉末混凝土RPC (Reactive Powder Concrete)是一种具有高强度、高韧性、高耐久性的超高性能混凝土材料,能有效地克服目前普通混凝土结构中存在的问题。但由于RPC的基本配制和普通混凝土不同,造成了它对各组分及生产过程的要求较高,硅粉的掺入、高效减水剂和钢纤维的使用以及较高的成型和养护条件,都提高了RPC的生产成本,故本文提出采用普通混凝土和RPC的组合构件,即在受拉区使用活性粉末混凝土,在受压区二次浇注普通混凝土,从而充分利用两种材料的材料特性。本文主要对组合构件的弯曲受力性能进行研究,对组合构件在弯矩作用下的受力和变形性能进行理论分析,得到二者共同工作以及最后破坏的全过程,根据组合构件的应力分布分析其抗裂性,推导组合构件在弯矩作用下的开裂弯矩和正截面承载力,为组合构件应用于工程实践提供相关的数据以供设计施工参考。由于普通混凝土的受压本构关系和RPC的受拉本构关系均采用非线性本构关系,故本文采用ABAQUS软件对组合构件进行建模分析,通过对模型计算分析得到构件的正截面抗弯承载力、刚度和挠度等数据,并与普通钢筋混凝土梁的建模计算结果进行对比。由于二次浇注的普通混凝土和RPC之间会产生较大的收缩徐变差,本文通过模拟普通混凝土的收缩和前期徐变,利用力学原理和变形协调推导出普通混凝土的拉应力以及活性粉末混凝土RPC中的拉压应力公式。对于组合构件,由于普通混凝土与RPC的结合面是受力的薄弱环节,研究提高结合面的抗剪强度,确保结合面能有效传力的方法,并推导计算界面剪应力,分析二者连接界面是否会产生滑移,以解决普通混凝土和RPC共同工作问题。
[Abstract]:Reactive Powder reactive concrete (RPC) is a kind of super high performance concrete material with high strength, high toughness and high durability. It can effectively overcome the problems existing in ordinary concrete structures at present. However, because of the difference between the basic preparation of RPC and ordinary concrete, the higher requirements for each component and the production process, the incorporation of silica fume, The use of superplasticizer and steel fiber, as well as the high conditions of forming and curing, all increase the production cost of RPC. Therefore, this paper proposes to adopt the combination of ordinary concrete and RPC, that is, to use reactive powder concrete in tensile zone. The second pouring of ordinary concrete in the compression zone makes full use of the material properties of the two kinds of materials. In this paper, the bending behavior of composite members is studied, and the mechanical and deformation behaviors of composite members under the action of bending moment are analyzed theoretically, and the whole process of joint work and final failure of composite members is obtained. According to the stress distribution of composite members, the crack resistance of composite members is analyzed, and the cracking moment and normal section bearing capacity of composite members under the action of bending moment are deduced, which provides relevant data for the application of composite members in engineering practice to provide reference for design and construction. Because the compressive constitutive relation of ordinary concrete and the tensile constitutive relation of RPC are both nonlinear constitutive relations, the ABAQUS software is used to model and analyze the composite members in this paper. The data of flexural bearing capacity, stiffness and deflection of normal section are obtained by the model analysis, and the results are compared with those of ordinary reinforced concrete beams. Due to the large shrinkage and creep difference between the secondary pouring ordinary concrete and RPC, this paper simulates the shrinkage and early creep of ordinary concrete. The formula of tensile stress of ordinary concrete and tension-compression stress of reactive powder concrete (RPC) is derived by means of mechanical principle and deformation coordination. For composite members, because the joint plane between ordinary concrete and RPC is the weak link of the force, the method of improving the shear strength of the bonding plane to ensure the effective transfer of force on the joint surface is studied, and the interface shear stress is deduced and calculated. In order to solve the problem of common concrete and RPC, the paper analyzes whether the interface between them will slip.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU375.1

【参考文献】