三轴试验橡皮膜与滤纸修正比较分析

Comparative Analysis of Rubber Membrane and Filter Strips Correction in Triaxial Test

为了补充国内土工试验规范没有关于橡皮膜与滤纸的修正规定的不足,本文通过对比分析美标ASTM、英标BS及国际标准ISO不同规范中对橡皮膜与滤纸修正的规定,总结其修正要点,并结合试验数据分析得出相关的结论。ASTM、ISO修正偏大,BS修正偏小。橡皮膜与滤纸的修正对软土的影响较大,对硬土的影响较小。c_(uu)<50 kPa时,内聚力c值变化不大,基本小于5%。修正后的内摩擦角j修正值最大可达85%总体上比修正前小,数据更为合理。c_(cu)<50 kPa时,进行橡皮膜与滤纸修正后的内聚力c值均变小,总体上ccu越小,内聚力c值修正比例越大,修正后的内摩擦角j变化不大。

In order to supplement the chinese geotechnical test specifications which lack the regulations on the correction of rubber membrane and filter strips,summarizes the key points of the correction by comparing and analyzing the regulations of ASTM,BS and ISO standards on the correction of rubber membrane and filter strips,and draws relevant conclusions based on the analysis of test data.The correction of ASTM and ISO is larger,while the correction of BS is smaller.The correction of rubber membrane and filter strips has a greater impact on soft clay and a smaller impact on hard clay.When c_(uu) is less than 50 kPa,the change of cohesion c value is not significant,basically less than 5%.The maximum corrected value of internal friction angleφcan reach 85%,which is generally smaller than that before correction,and the data is more reasonable.When c_(cu) is less than 50kPa,the cohesion c value after the correction of rubber membrane and filter strips decreases,and generally,the smaller the c_(cu) is,the greater the correction ratio of cohesion c value is,and the change of internal friction angleφafter correction is not significant.