用美国产MTS815程控伺服岩石刚性试验机和AE210声发射测试系统,对6个不同方向的隧道主洞定向砂岩样进行单轴压缩试验;同时测定岩样在受压过程中产生的声发射信号.通过能量累计(对数)、振铃计数、荷载与到达时间的关系图,导入CAD,综合选定6个方向Kaiser效应点.根据弹性力学理论基础,用工程Maple软件计算出3个主应力的大小和方向.为了验证该方法选取特征点计算结果的可靠性,用有限元Phase软件对工程区区域构造应力场特征进行数值分析.结果表明:试验测试值与应力数值模拟值较相近,说明声发射试验结果可靠;并得出该隧道现代地应力场基本应力值为14.48 MPa,应力场方向为EW向,此结果对隧道设计和施工有十分重要的意义.%In order to improve the bearing capacity of the anchor, This article uses the small particles pisolite concrete as anchoring agent to replace the cement mortar and add the anchor thorn in the anchor. Then the bolt bearing capacity of the pull out test was carried out and research is mainly focused on the relationship between bolt bearing capacity, anchor thorn layer, strength of concrete and the block size. From the test, below conclusions were gotten: firstly, changing the structure of anchor can improve the effect of bearing capacity significantly, the bearing capacity of single anchor thorn is 1.2 to 1.7 times than the polished anchor, secondly, the different bolt bearing capacity has a linear relation with pisolite concrete intensity under the condition that anchor thorn has a certain strength and the bearing capacity increased slowly with the increase of concrete strength; thirdly, under the condition of single anchor thorn, the bearing capacity of anchor increases with the size of the test cube, which represents that given a certain level of anchor thorn stress, the anchor bearing capacity is positively related to the thickness of the concrete.
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