实验室用小型单桥静力触探探头的标定

Calibration of a Miniature Cone Penetrometer for Geotechnical Model Test

为了测试实验室模型试验土的力学性质,制作了小型化单桥静力触探探头,对其进行了量测系统的标定试验,比贯入阻力与土的不排水抗剪强度统计关系研究,并与生产用静力触探测试结果和现有经验公式作了对比分析.试验和研究结果表明:本静力触探探头量测系统标定曲线呈线性,其灵敏度为262×10-12 Pa-1;本静力触探与生产用静力触探测得的比贯入阻力接近,且前者的灵敏度高于后者;得出的饱和重塑黏性土比贯入阻力与不排水抗剪强度统计关系公式与交通部一航局的经验公式很接近.本静力触探探头可用于实验室饱和重塑软黏性土力学性质的比较及不排水抗剪强度值的测试.

A miniature single bridge cone penetrometer was manufactured to measure the mechanical properties of soils in the geotechnical model tests. Such tests and researches were carried out to calibrate this miniature penetrometer as calibration of the penetrometer＇s measuring system, investigation of statistical relationship between specific penetration resistance （ps） and undrained shear strength （c,）, contrast of penetration test results between the miniature and standard penetrorneters, and comparison of this statistical relationship with current empirical equations. The results show that the calibration curve of the miniature penetrometer＇s measuring system is linear with 262×10^-12 Pa-1 of its sensitivity. Penetration resistance-depth curve fora remoulded clay foundation by the miniature penetrometer is close to, but more delicate than the curve by standard penetrometer. The ps-cu relationship obtained by authors is consistent with an empirical equation proposed by China Communication First Design Institute of Navigation Engineering. Thus, this miniature penetrometer can be used for comparison of the mechanical properties of saturated remoulded clays in laboratory as well as measuring their undrained shear strength values.