型钢活性粉末混凝土构件受力性能及设计方法

The steel reinforced concrete structures are gradually developing in the direction of super high and large span, and they are also more and more applied in freeze-thaw areas and erosion environments, in which higher requirements for the mechanics and durability of concrete are put forward. Therefore, steel reinforced reactive powder concrete structures are proposed in this project, in which reactive powder concrete are applied in conventional steel reinforced concrete structures, based on the advantages of high strength and durability of reactive powder concrete. The new composite structures have the advantages of small section size, high bearing capacity, light weight, small earthquake action, perfect seismic performance and high durability. At present, the investigation and design of such new composite structures are not adequate. For this purpose, tests and theoretical analysis on components of the steel reinforced reactive powder concrete structure were conducted. The bond-slip properties between steel and reactive powder concrete, the bending and shear performance of steel reinforced reactive powder concrete beam, and the compressive and hysteretic behaviour of steel reinforced reactive powder concrete column will be investigated. As a result, bonding failure mechanism between steel and reactive powder concrete will be revealed and calculated theory and design method of bearing capacity, stiffness and crack width for steel reinforced reactive powder concrete components will be proposed, which provide necessary theoretical foundation for promoting engineering applications of such new type of composite structures.

型钢混凝土组合结构正逐渐向超高、超大跨度等方向发展，同时其也越来越多的应用于冻融地区和侵蚀环境中，这对混凝土的力学和耐久性能提出了更高的要求。为此，本项目拟结合活性粉末混凝土高强度和高耐久性的优点，提出将活性粉末混凝土应用于型钢混凝土组合结构中，形成型钢活性粉末混凝土组合结构。此类新型的组合结构具有截面尺寸小、承载能力高、自重轻、地震作用小、抗震性能好以及耐久性高等优点。目前关于此类新型组合结构的研究与设计还不够充分。因此，本项目拟开展型钢活性粉末混凝土基本构件的受力性能试验与理论分析，深入研究型钢活性粉末混凝土粘结滑移性能、型钢活性粉末混凝土梁的受弯和受剪性能、型钢活性粉末混凝土柱受压以及滞回性能，拟揭示型钢活性粉末混凝土粘结破坏机理，提出型钢活性粉末混凝土构件承载力、裂缝宽度和刚度等计算理论和设计方法，为推广此类新型组合结构的工程应用提供必要的理论基础。

随着社会经济的发展，建筑结构逐渐向超高层、超大跨度等方向发展，且也越来越多的应用于冻融和侵蚀环境，这对混凝土的力学和耐久性能提出了更高的要求。为此，本项目结合型钢混凝土与活性粉末混凝土结构的优点，提出“型钢活性粉末混凝土结构”，并从多个方面开展了型钢活性粉末混凝土构件的受力性能研究。主要研究内容包括：型钢活性粉末混凝土粘结滑移性能、型钢活性粉末混凝土梁受弯和受剪性能、型钢活性粉末混凝土梁抗震性能、型钢活性粉末混凝土短柱轴压性能、型钢活性粉末混凝土柱偏压性能、型钢活性粉末混凝土柱抗震性能。通过试验和有限元分析，提出了型钢和活性粉末混凝土之间的特征粘结强度的计算公式，建立了平均粘结应力-滑移曲线的本构模型；建立了型钢活性粉末混凝土梁正截面受弯承载力计算模型，提出了相应的正截面受弯承载力、刚度及裂缝宽度计算公式；建立了型钢活性粉末混凝土梁的斜截面受剪承载力计算公式和实用设计方法；考察了配筋率、配钢率、配箍率以及混凝土强度对型钢活性粉末混凝土梁抗震性能的影响；提出了考虑箍筋约束作用的型钢活性粉末混凝土短柱轴压承载力计算方法；建立了型钢活性粉末混凝土柱偏心受压正截面承载力计算模型，推导了偏心距增大系数公式，提出了正截面承载力计算公式；考察了轴压比、含钢率以及体积配箍率等参数对型钢活性粉末混凝土柱抗震性能的影响，建立了荷载-位移恢复力模型。研究成果可为此类采用新材料的型钢混凝土结构的推广应用提供试验与理论支撑。