土工布加固软土地基的机理试验研究

Experimental study on the mechanism for geotextile reinforcing soft ground soil

土工布与土体的界面摩擦力是衡量其对土体加固效果的关键因素,本文首先根据土工布与土体拉拔摩擦试验的机理,设计并制作了界面剪切测试仪,该试验测试仪具有试验精度高、应用广泛和操作步骤简单的特征,然后采用此测试仪对土工布与砂土的界面摩擦力进行了试验研究,试验参数包括不同的竖向压力、土工布层数和砂土含水率。试验结果表明:增加竖向压力能够显著提高土工布与土体的界面摩擦力;相同竖向压力作用下,土工布层数超过2层时,对其界面摩擦力提高并不显著;相同条件下,当砂土含水率超过5%时,提高砂土含水率能够显著降低土工布与土体界面摩擦力。这些研究结果可为土工布加固土体的设计和施工提供依据。

The interface friction between geotextile and soil is the key factor to measure the effect of the reinforced soil. According to the geotextile and soil pullout mechanism from friction tests, the contact surface shear tester is designed and produced. The testing instrument has the characteristics with high precision, wide application and simple operation. The interfacial shear between geotextile and soil are studied by using the tester, and the testing parameters include the different vertical pressures, geotextile layer and soil moisture content. The testing results show that increasing the vertical soil pressure can significantly improve the interfacial friction force of geotextile and soil; under the same vertical pressure, the shear friction isn＇ t improved significantly when the geotextile is more than 2 layers; under the same conditions, when the sand moisture content exceeds 5% , increasing soil water content can significantly reduce the interfaeial friction of the geotextile and soil. The study results can provide the basis for the design and construction of geotextile reinforced soil.