加气混凝土与普通混凝土黏结界面剪切性能试验

Shear experimental study on the bonded interface properties between autoclaved aerated concrete and ordinary concrete

摘要:

密肋复合墙体是由钢筋混凝土肋构成的框格与内嵌轻质加气混凝土砌块组成, 是密肋复合墙结构的主要承力构件.由于密肋复合墙体特殊的制作工艺, 在混凝土肋与加气混凝土砌块相接触的位置处形成一黏结界面, 而此类黏结界面的性能目前仍不明确, 为此, 有必要在材料层次上对加气混凝土砌块与普通混凝土黏结界面性能进行研究.本文以密肋复合墙结构为研究背景, 采用棱柱体剪切试验的方法测定加气混凝土砌块与普通混凝土黏结界面性能, 分析黏结界面倾斜角度对试件的破坏形态和界面强度的影响.结果表明, 当倾斜角较小时, 试件发生界面剪切破坏, 而倾斜角增大, 试件趋向于发生轻质加气混凝土砌块材料破坏；根据试验数据拟合出τ_n关于σ_n的二次界面破坏包络线方程, 并分析界面变形特性, 提出界面切应力-滑移位移特征曲线, 为密肋复合墙结构构件层次和结构层次力学性能的研究提供理论和数值计算依据

Abstract:

Multi-ribbed wall structure (MRWs) is composed of densely distributed ribbed frames, including ribbed beams and columns, and autoclaved aerated concrete (AAC) is filled inside the ribbed frames. Because of the special production process, there is a bonded interface of which property is still undefined between ribbed frames and infilled AAC. To study the properties of bonded interface of ordinary concrete and AAC, the experimental study is necessary on the material level. On the background of multi-ribbed composite wall structure, the slant shear test was used to measure the bonded interface properties of ordinary concrete and AAC. This paper analyzed the influence of bonded interface joint angle to interfacial strength and proposed the failure envelope of bonded interface. Based on test results, the equation between τ_n and σ_n of the bond failure envelope is fitted which provides a valuable basis of theoretical and numerical solutions for mechanical properties of multi-ribbed composite wall structures