摘要
SDG无核密度仪是一种无损快速的压实土干密度测试仪器,其开发和引进时间较短,缺少使用经验。基于黄土地区古土壤的SDG和灌砂法、烘干法测试结果,分析了SDG标定的作用和效果,SDG测试产生误差的原因,绘制了干密度测试结果的误差分布图。结果表明,标定的作用在于使仪器内置的计算模型与实际更接近,但仍与实际存在差别是其产生测试误差的原因;压实土真实的干密度和质量含水率均会影响SDG干密度测试结果,在质量含水率与干密度组成的坐标系中,干密度测试结果相对可靠的区域为一斜向上的条带状区域;只有当压实土的质量含水率在较小区间分布时,SDG测试得到的不同试样干密度大小排序才和实际一致。
Soil density gauge（ SDG） is a nondestructive technique that can quickly measure the dry density of compacted soil. However,the technique has been introduced for only a short time and it is not mature enough,thus it needs further in-depth investigation. To this end,this work investigates the effectiveness of the SDG method,by comparing the results from the SDG method,oven-drying method,and sand cone method. Distribution of the errors in the estimated dry density was also presented. The results show that the errors are caused by the difference between the analytical model in the SDG and the actual model. The calibration in the SDG can improve the accuracy of the model and hence reduce the errors. In addition,it has been found that the accuracy of the SDG technique is also related to dry density and water content of the associated compact soil. It has been shown that in the coordinate of dry density against water content,high accuracy of the SDG technique is shown in a strip area. When the water content of the compact soil distributes in a wide range,soil with higher dry density estimated by the SDG technique is not always the higher one in practice.
作者
杜伟飞
刘争宏
张继文
于永堂
程新星
Du Weifei Liu Zhenghong Zhang Jiwen Yu Yongtang Cheng Xinxing(China JK Institute of Engineering Investigation and Design Co. Ltd., Xi, an 710043, P.R. China Shaanxi Key Laboratory of Engineering Behavior and Foundation Treatment for Special Soil, Xi, an 710043, P.R. China)
出处
《地下空间与工程学报》
CSCD
北大核心
2017年第5期1263-1270,共8页
Chinese Journal of Underground Space and Engineering
基金
陕西省科技统筹创新工程计划项目(2016KTZDSF04-05-01)
国家科技支撑计划(2013BAJ06B00)
