多因素耦合条件下龄期对重塑黄土湿陷性的影响

Effect of age on the remolded loess wet-collapsibility in multiple-factorial coupling condition

为探索黄土处理后取样测定湿陷性的合理时间节点,以重塑黄土的含水量、干密度和龄期为因素,设计混合均匀试验方案,研究多因素耦合条件下龄期对重塑黄土湿陷性的作用规律.应用最小二乘拟合,建立湿陷系数与含水量、干密度、龄期的非线性回归数学模型.结果表明,影响湿陷系数的主要因素是干密度,其次是含水量和龄期;含水量和干密度的作用为负效应,龄期的作用为正效应.龄期干密度的交互作用为正效应,龄期含水量、含水量干密度的交互作用为负效应;交互作用的因素主次顺序为龄期干密度、龄期含水量、含水量干密度.取样测定湿陷性的合理时间节点与扰动黄土土样的干密度和含水量有关.试验所选水平范围内,龄期大于21d后,湿陷系数均基本趋于稳定,可取21d作为扰动黄土测定湿陷性的合理时间节点.

In order to explore the reasonable time node for sampling-measuring of measured wet-collapsibility of treated loess,its moisture,dry density,and age were taken as factors to design a mixture-uniformization test program and research the pattern of effect of age on the wet-collapsibility of remolded loess in multifactorial coupling condition.A nonlinear regressive mathematical model was established with least squares fitting for relating the coefficient of wet-collapsibility to the moisture,dry density,age.The result showed that the main factors affecting the coefficient of wet-collapsibility would be the dry density,followed by the moisture and age,where the effect of the moisture and dry density would be negative and that of the age positive.The interactive effect of the age with the dry density would be positive and that of age with moisture and moisture with dry density would be negative,the priority of interactive effect being agedry density,age-moisture,moisture-dry density.The reasonable time node for sampling-measuring of wetcollapsibility would be dependent on the dry density and moisture of disturbed loess sample.In the selected range for the experiment,the coefficient of wet-collapsibility would be basically stable when the age was greater than 21 days.Therefore,21-day could be taken as the reasonable time node for measuring the wetcollapsibility of the disturbed loess.