齐齐哈尔地区粉质黏土冻胀特性试验研究

黑龙江省受寒冬负温影响，容易引起渠道渗漏、地基下陷、轨道不顺等问题，这增加了工程建设难度。为解决实际问题，以齐齐哈尔地区粉质黏土为研究对象，进行封闭系统下的人工冻结试验，对冻胀试验数据进行分析，研究不同含水率、干密度、冷端温度及冻结速率条件下土体的冻结过程及冻胀率的变化规律。试验结果表明:冻胀率在含水率高、干密度大、冷端温度低、冻结速率低的条件下，土体冻胀现象更为显著，且冻胀率与4个因素相关性较好。冻胀正交分析结果表明:冷端温度对冻胀率的影响程度最弱，干密度较强，含水率的影响最为剧烈。采用SPSS统计分析软件，建立含水率、干密度和冷端温度三因素综合影响下的冻胀率多元线性回归模型，模型拟合效果好、可信度高、精度高，满足实际需求，操作简便，可用于粉质黏土的相关计算和预测。

Experimental study on frost heaving characteristics of silty clay in Qiqihar region

Heilongjiang Province is affected by cold winter negative temperature, which is easy to cause channel leakage, foundation subsidence, track irregularity and other problems, which increase the difficulty of engineering construction. In order to solve the practical problems, taking the silty clay in Qiqihar region as the research object, the artificial freezing test in the closed system was carried out, and the frost heave test data were measured and analyzed, to investigate the freezing process of soil and the change of the frost heaving ratio under different moisture contents, dry densities, cold end temperatures and freezing rates. The test results show that: under the conditions of high moisture content, high dry density, low cold end temperature, and low freezing rate, the phenomenon of soil frost heaving is more significant, and the frost heaving ratio has a good correlation with the four factors. The results of frost heave orthogonal analysis show that the influence of cold end temperature on frost heaving rate is the weakest, the influence of dry density is strong, and the effect of moisture content is the most severe. Using SPSS statistical analysis software, a multiple linear regression model of frost heave rate is established under the comprehensive influence of moisture content, dry density and cold end temperature. The model has the advantages of good fitting effect, high reliability, high accuracy, meeting the actual needs, simple operation, and can be used for the correlation calculation and prediction of silty clay.