黄土路基回弹模量湿度预估及修正系数确定

为了研究黄土路基湿度与强度的变化规律,调研了大量路基湿度预估模型,结合黄土地区气候环境特征,确定FredlundXing模型作为黄土地区路基湿度预估模型;选取了16种土样做物性参数试验,结合预估模型,得到了黄土路基平衡湿度范围质量含水率为16%~19%,体积含水率为29%~35%;现场实测霍候一级公路、宁夏桃同高速公路以及晋阳高速公路路基平衡湿度,实测值与预估值之差为-1.4%~1.7%;在此基础上,选取7种代表性土样做最佳含水率及平衡湿度情况下的动态回弹模量试验,推荐了山西省黄土路基湿度修正系数,晋北地区修正系数为0.4~0.5,晋南地区为0.5~0.6.

Determination of Correction Coefficient and Moisture Prediction of Loess Subgrade Resilient Modulus

Large moisture prediction models were investigated to study the change law between moisture and strength of loess subgrade. Fredlund & Xing was determined as prediction model of subgrade moisture in loess area according to climate characteristics. Physical parameters of 16 soil samples were tested combined with the prediction model. The results show that mass water content is 16% ~19% and volumetric water content is 29% ~35% about equilibrium moisture range of loess subgrade, equilibrium moisture ranges of Huohou first-class highway, Ningxia Taotong highway and Jinyang highway were measured in field, the value between the measured and the estimated is about ( -1. 4 ~1. 7 )%. Optimum moisture content and dynamic resilient modulus of 7 representative soil samples under equilibrium moisture were tested, and the humidity correction coefficient of Shanxi loess subgrade, which the north area is 0. 4~0. 5, and the south area is 0. 5~0. 6, was recommended.