基于轴平移技术测试方法的误差修正与评估

摘要

为完善轴平移技术在非饱和土应用中的局限性,根据轴平移测试技术误差的产生机理,提出修正轴平移测试技术在量测土-水特征曲线(soil water characteristic curve,SWCC)误差的计算方法.结合张力计的测试结果,采用误差评估理论评估该方法的准确性.研究表明,应用轴平移测试技术量测的土-水特征曲线中各基质吸力所对应的含水率减去填充水所占的含水率,可得到修正后的含水率,有效降低了轴平移技术测试SWCC的系统误差.该方法的修正效果随着基质吸力的增大而更加明显,适合修正高基质吸力时的土-水特征曲线.%In order to improve the limitations of the application of axial translation technique in unsaturated soils, based on the mechanism of the experimental error of axis translation test technique, we propose a reasonable and simple calculation method to correct the error of the measurement of soil water characteristic curve (SWCC) and improve the accuracy of the application of axis translation technique.Combining with the tensiometer test results, we use the error evaluation theory to evaluate the results of the modified calculation method.We find that the modified water content can be obtained by the water content corresponding to each matric suction of SWCC, which is measured by axis translation technique, subtracting the water content of filling water.This greatly reduces the system error of axis translation test technique for SWCC.The effect of correction method is more obvious with the increase of matrix suction force.The method is more suitable for the correction of high matrix suction.