三维裂纹布置角度对砂浆材料强度的影响

利用伺服控制试验系统及声发射设备对含有单椭圆裂纹的非均质砂浆材料进行物理试验，获得了单轴加载作用下不同布置角度的三维内部裂纹试样的全应力-应变曲线和声发射数据。找到了声发射数据与应力-应变曲线的对应关系。根据对应关系，判断出试样的起裂应力及破坏应力。分析了裂纹布置角度对材料强度的影响，分析表明：裂纹与加载方向为45º夹角时最难破坏，与加载方向成60º夹角时最容易破坏。此外，裂纹尖端起裂应力为试样极限强度的86.07 %～87.42 %。

Influence of 3D-crack angle on strength of mortar ematerial

A series of experimental tests for heterogeneous brittle mortar material containing pre-existing internal crack were carried out . The complete stress-strain curves and acoustic emission data of the mortar material in uniaxial compression were obtained using acoustic emission equipment and serve-controlled test machine. Based on these data, the relation of complete stress-strain curves and acoustic emission data were searched .Then the influence of crack angle on the strength of mortar specimens were analysed judging the initiation stress and failure stress of mortar specimens .It is concluded that the strength of mortar specimens is the lowest at α=60oand the highest atα=45o. In addition, the initiation stress on the tips of cracks is about 86.07%-87.42% of the failure strength of the specimens.