蒸压粉煤灰—砂加气混凝土应力—应变本构关系及其砌体力学性能试验研究

发布时间：2018-03-19 17:51

本文选题：粉煤灰加气混凝土　切入点：全曲线　出处：《长沙理工大学》2013年硕士论文　论文类型：学位论文

【摘要】：随着国家的发展及能源的巨大消耗，建筑节能已占有十分重要的地位，对新型墙体节能材料已有新的需求。本文对新型节能墙体材料蒸压粉煤灰-砂加气混凝土进行基本的力学性能研究，并对其进行单轴受压应力-应变全曲线试验，分析研究其本构关系，研究了其砌体的力学性能等。本文主要的研究内容如下：（1）研究了蒸压粉煤灰-砂加气混凝土的基本力学性能，进行了立方体抗压强度试验和轴心抗压强度试验；根据相关试验结果和破坏形式，建立了轴心抗压强度与立方体抗压强度的关系式，抗压强度与试件尺寸之间的关系式及轴力抗压强度与干密度的关系式；（2）对蒸压粉煤灰-砂加气混凝土的单轴受压应力-应变全曲线的试验方法进行了设计，说明其试验原理及方案设计的可行性。通过对试验测试结果进行分析研究，得出其破坏过程分上升段和下降段分别进行描述，分析试件的破坏形式；给出蒸压粉煤灰-砂加气混凝土的全曲线试验曲线图，对单轴受压应力-应变全曲线的几何特征进行分析，并与混凝土全曲线比较异同；（3）对影响蒸压粉煤灰-砂加气混凝土的相关参数进行了试验研究，主要包括轴心抗压强度、试件尺寸及含水率与弹性模量的关系，峰值应变与抗压强度的关系及泊松比的取值等。对单轴受力应力-应变全曲线本构方程进行研究，将全曲线分为上升和下降段，，其中下降段分为下降段和斜直线段；上升段采用五次方程描述，下降段的两部分分别用不同的有理式表示，并对其连续性、分界点及计算值与试验值的符合情况进行了相应的研究；（4）对蒸压粉煤灰-砂加气混凝土砌体抗压强度试验进行了研究，分析抗压试件的破坏特征；对砌体抗压强度进行统计分析，得出灰缝厚度、尺寸等对砌体抗压强度的影响；根据拟合公式得出的抗压强度平均值与试验值比较吻合，得出了试验试块的设计值、标准值；根据统计数据导出的计算公式得出的设计值均较规程值大，说明计算公式可行且更安全；（5）研究了蒸压粉煤灰-砂加气混凝土砌体沿通缝弯曲抗拉强度试验，并对试验现象的破坏特征和破坏形态进行了阐述，得出了相应的试验结果。采用粘结剂砌块要比采用普通砂浆砌块的弯曲抗拉强度要提高20%，得出了沿通缝弯曲抗拉强度的平均值，式中的K4值与试验数据结果基本相符，对于沿通缝弯曲抗拉强度标准值与设计值，建议采用粘结剂砌筑蒸压粉煤灰-砂加气混凝土砌块砌体。
[Abstract]:With the development of the country and the huge consumption of energy, building energy conservation has played a very important role. In this paper, the basic mechanical properties of autoclaved fly-ash sand aerated concrete are studied, and the uniaxial compression stress-strain full curve test is carried out. The constitutive relation and mechanical properties of masonry are analyzed and studied. The main contents of this paper are as follows:. 1) the basic mechanical properties of autoclaved fly-ash sand aerated concrete are studied, and the cube compressive strength test and axial compressive strength test are carried out. The relationship between axial compressive strength and cube compressive strength, between compressive strength and specimen size, and between axial compressive strength and dry density is established. (2) the test method of the stress-strain curve of autoclaved fly-ash sand aerated concrete under uniaxial compression is designed, and the principle of the test and the feasibility of the scheme design are illustrated. The test results are analyzed and studied. The failure process is described in ascending section and descending section, and the failure form of the specimen is analyzed, and the curve curve of autoclaved fly-ash sand aerated concrete is given. The geometric characteristics of the full stress-strain curve under uniaxial compression are analyzed and compared with the whole curve of concrete. The related parameters affecting autoclaved fly-ash sand aerated concrete are studied, including axial compressive strength, the relationship between specimen size, moisture content and elastic modulus. The relationship between peak strain and compressive strength and Poisson's ratio. The constitutive equation of stress-strain curve under uniaxial stress is studied. The whole curve is divided into ascending and descending segments, in which the descending section is divided into descending section and oblique straight section. The ascending stage is described by the quintic equation, the two parts of the descending section are expressed by different rational expressions, and the continuity, the boundary point and the coincidence between the calculated value and the experimental value are studied. 4) the compressive strength test of autoclaved fly-ash sand aerated concrete masonry is studied, and the failure characteristics of compressive concrete are analyzed, and the influence of the thickness and size of ash seam on the compressive strength of masonry is obtained by statistical analysis of the compressive strength of masonry. The average value of compressive strength obtained from the fitting formula is in good agreement with the test value, and the design value and standard value of the test sample are obtained, and the design values derived from the calculation formula derived from the statistical data are all larger than those of the standard value. It shows that the formula is feasible and safer. The bending tensile strength test of autoclaved fly-ash sand aerated concrete masonry along the pass joint is studied, and the failure characteristics and failure modes of the test phenomenon are described. The corresponding test results are obtained. The bending tensile strength of the binder block is 20 higher than that of the ordinary mortar block. The average value of bending tensile strength along the pass joint is obtained, and the K4 value in the formula is basically consistent with the test data. For the standard value and design value of flexural tensile strength along the pass joint, it is suggested to use binder to build autoclaved fly-ash sand aerated concrete block masonry.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU528

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