静力触探实验在土层划分中的应用研究

Studies on the Application of Soil Stratification Based on Cone Penetration Test

3种静力触探实验与钻孔取样的对比结果说明:根据单桥静力触探、双桥静力触探和孔压静力触探获得的实验参数,均可通过绘制各类曲线,并利用曲线特点确定各土层界面的位置,划分土层.其中,孔压静力触探实验划分土层的精度最高,且未发现错判或漏判土层的情况;双桥静力触探实验的结果优于单桥静力触探实验,但两者均存在较大的误差,且有时会出现错误判断土层的情况.考虑到钻孔取样的结果与取样的数目有很大关系,取土过程对场地有扰动等情况,建议在未来的工程实践中可更多地考虑使用静力触探实验,特别是采用孔压静力触探实验划分土层.

The results of soil stratification from the single bridge cone penetration test （CPT）, the double bridge CPT, Piezoncone penetration test （CPTU） and the drilling ＆ sampling test were compared and showed that： all the three kinds of CPT can determine the positions of each soil layer interface and the stratification according to the charac- teristics of the curves drawed from their corresponding CPT parameters. Soil stratification from CPTU had the highest accuracy, and no wrong or missed justice was found. Stratification from the double bridge CPT was better than that of the single bridge CPT, but both had found errors, and sometimes there was wrong or missed justice. Considering that the results from drilling and sampling test largely depends on the numbers of samples, and the process of borrow soil has disturbance, etc. , it was recommended to more use the CPT in the future engineering practice, especially to use the CPTU in soil stratification.