深孔原位直剪测试仪的研制及应用

原位直剪试验是获取土体抗剪强度参数的有效方法。在参考室内和原位直剪仪后，研制出一种深孔原位直剪测试仪，介绍了结构组成、工作原理和技术优点。该设备可测定深埋地下软土、细砂的抗剪强度。设备的取样方式为测试杯直接插入土中取样，实现对土壤样本扰动最小化。测试杯中装有高精度传感器，通过对土体垂直和水平加载的方式，压力传感器可以测定土体的应力参数。该设备体积小、易携带，可自动采集数据，适用于复杂的现场环境。使用该设备对砂土进行抗剪试验，获得的抗剪强度参数与室内直剪试验的结果接近。最终结果表明，深孔原位直剪测试仪可应用于砂土、软土的抗剪强度测试。

Development and Application of Deep Hole In-situ Direct Shear Test Apparatus

In-situ direct shear test is an effective method for obtaining the strength parameters.After investigating a set of direct shear apparatus for lab test，a deep hole in-situ direct shear test apparatus was developed，and the structure，working principle and technical advantages of the apparatus are introduced.This device can test shear strength of soft soil and fine sand in deep earth.That the device is directly inserted into the soil by the test cup for sampling can minimize the disturbance of the soil sample.The test cup is equipped with a high precision sensor，which can be used to determine the stress parameters of the soil by means of the vertical and horizontal loading of the soil through the stress sensor.The device is small in size and portable and can automatically achieve data collection.So，it is suitable for the scene with complex environment.The shear strength parameters of sands obtained by this device are approaching to that of the indoor direct shear test.The final results show that the deep hole in-situ direct shear test apparatus can be used to test shear strength of fine sand and soft soil.