组砌方式对生土基砌体受压力学性能的影响

Influences of Bond Pattern on Compressive Properties of Earth Brick Masonry

为了研究组砌方式对生土基砌体单轴抗压性能的影响,确定生土基砌体抗压强度试验标准试件的组砌方式,选取2种传统土坯和2种新型生土砖制作砌体试件,通过单轴抗压试验对3种不同组砌方式的砌体试件进行测试,分别从破坏形态、抗压强度、弹性模量及泊松比等方面分析了组砌方式对生土基砌体单轴抗压性能的影响,基于层次分析法确定了生土基砌体抗压强度测试的最优组砌方式.结果表明:轴压作用下叠砌试件多发生局部破坏和劈裂破坏,带有竖向灰缝的砌体试件均发生由竖向裂缝引起的贯穿破坏;各类生土基砌体的抗压强度、弹性模量和泊松比呈现相同的规律,抗压强度及弹性模量由大到小依次为叠砌、全顺、梅花丁,泊松比由大到小依次为梅花丁、全顺、叠砌;全顺试件在适用性、操作性、数据稳定性、试件破坏形态代表性及复演性等方面较为均衡,建议采用该组砌方式作为生土基砌体抗压强度试验标准试件组砌方式.

To study the influence of different bond patterns on the uniaxial compressive performance of the earth block masonry prism and to determine the bond pattern of specimen for measuring the compressive strength of earth block masonry prism,two kinds of traditional adobe and two new types of earth brick were selected to build masonry prisms.The uniaxial compression tests were performed on three kinds of masonry to analyze the influences of bond pattern on masonry compressive properties from failure mode,compressive strength,elastic modulus and Poisson’s ratio,respectively.Based on the analytic hierarchy process,the optimum specimen bond pattern for measuring the compressive strength of earth brick masonry was determined.It is shown that local failure and splitting failure occurred in stacked specimens and penetration failure caused by vertical cracks occurred in the specimens with vertical joints.The compressive strength,elastic modulus and Poisson’s ratio of all kinds of masonry show the same variation regularity:compressive strength and elastic modulus in order from strength to weakness are stack bond,stretcher bond,flemish bond and inbond,and the Poisson’s ratios in descending order are inbond,flemish bond,stretcher bond and stack bond.Because of the superiority of stretcher bond in applicability,operability,data variation,specimen failure mode,and reproducibility,it was suggested to use this bond pattern as the standard bond pattern for testing the compressive strength of earth brick masonry.