T型触探测试软黏土不排水抗剪强度工程实践

Engineering practice of undrained shear strength determination of soft soil by T-bar penetration test

本文介绍了T型触探的研究现状、测试原理及其技术优点。选取天津某沿海软土场地,进行了工程实践,与静力触探测试结果、十字板测试结果进行了对比。测试结果表明:T型触探测试曲线变化趋势与静力触探基本一致;数值与十字板峰值强度相当。当不排水抗剪强度小于40k Pa时,T型触探测试结果稍高于十字板峰值强度;当不排水抗剪强度大于40k Pa时,二者测试结果基本相同。T型触探不需要上覆压力修正,不需要经验参数,有精确解,能方便地得到软黏土不排水抗剪强度随深度的变化曲线,是一种较好的原位测试手段。

The study status, testing principle and technical advantages of T-bar penetration test is introduced. The test is carried out in a soft ground in Tianjin,and then comparing the test results with static cone penetration test and vane shear test. It is shown that the changing tendency of T-bar penetration test curves is consistent with that of static cone penetration test and van shear test; the both peak values are similar. When the undrained shear strength is less than 40 k Pa,T-bar test result is slightly higher than vane shear test; when it is greater than 40 k Pa,the two test results are almost identical. The T-bar penetration test is a kind of good in-situ test method with many advantages such as interpretation without overlying pressure correction,no experience parameters needed,exact solutions,the changing curve with depth obtained easily.