波速测试法在冻结粉质黏土强度研究中的应用

The test research of frozen clay wave velocity under different from temperature and moisture content

采用超声波技术测定冻土强度指标和分析其影响因素是目前冻土学术界及冻土工程领域研究的重点课题,冻土纵波波速与温度和含水率关系研究是该课题研究的重要和关键内容。用SYC—2型超声波测试仪和20 kHz超声换能器实测了不同温度和不同含水率下冻结粉质黏土的纵波波速,对实验数据进行了分析,结果表明:含水量一定时,总的趋势是冻结粉质黏土纵波波速随冻结温度的降低而增加,-7℃是冻结粉质黏土波速增长的拐点,-20℃是冻结粉质黏土波速快速增长的拐点;冻结温度一定时,其纵波波速和冻土强度随含水率的增加有下降的趋势,含水率20%是纵波波速变化的拐点,含水率大于24%时,纵波波速增长趋于平缓。文章结论对冻土工程设计与施工及基坑挡土墙冻结工程有较强的参考价值。

It is just a hotspot in the field of frozen clay how measure and analyze strength,the relation research of the frozen clay lengthways wave velocity with the temperature and moisture content is important.Using SYC-2 type super voice wave testinstrument with energy changed equipment of 20 kHz had measured the lengthways wave velocity of frozen clay under the temperature and the moisture content.Under the foundation of analyzing the experiment data,know that the lengthways wave velocity of frozen clay increase with frozen temperature,in total trend,under the condition of the moisture content being constant.-7 ℃ is the turning point of frozen clay lengthways wave velocity increasing,-20 ℃ is the turning point of frozen clay lengthways wave velocity increasing quickly.Under the condition of the temperature being constant,the lengthways wave velocity of frozen clay lower with frozen clay moisture content,20% is the turning point of frozen clay lengthways wave velocity changing.When the moisture content is bigger than 24%,the lengthways wave velocity increase slowly.The article conclusion is important of Changchun frozen clay engineering design and constructions.