土工试验中的几个问题探讨

通过多组宁波和温州软土不同剪切速率的直剪固结快剪、不同预压时间下软土直剪固结快剪和三轴固结快剪试验中多样剪和多级剪的试验研究,表明①剪切速率对软土的抗剪强度影响较大,现有国家标准确定的0.8 mm/min剪切速率对软土并不合适;②预压时间超过6 h后软土强度增加不大;③对多样剪和多级剪而言,高灵敏度的软粘土两者差别较大,而对低灵敏度软粘土在掌握一定试验方法和试验技巧下,可用多级剪代替。这些结论对生产实践是有用的。

Discussion of Several Issues in Geotechnical Test

According to the test research from several pairs of Ningbo and Wenzhou soft soil by direct consolidation of fast shear at different shear rate,and test of soft soil by direct consolidation fast shear and triaxial consolidation fast shear in a variety cut and multi-level cut under different pre-press time,it indicates that 1;The speed of shear has significant influence on the anti-shear strength of soft oil,the current China standard of speed shear 0.8mm/min is not appropriate for the soft oil.2;The soft oil strength increase little when the pre-press time is more than 6 hours.3;to variety cut and multi-level cut,the difference between high flexible soft oil is distinct.While for low flexible soft oil,variety cut can be replaced by multi-level cut after the test skill and method are well mastered.This conclusions is very useful for the practice.