中文摘要：

黄土通常可作为公路路基主要的填筑材料,湿陷性黄土经压实后,很大程度消除了湿陷性,能够满足路基整体强度和稳定性的要求,但在季节冻土区,黄土路基运营几年后仍发生大量的不均匀沉降、塌陷等病害。为分析冻融循环作用下各级含水率对黄土湿陷性的影响,采用室内试验的方法,对湿陷性黄土进行不同的冻融次数,探究其在冻融循环过程中变形及冻融循环后湿陷情况。实验结果表明：冻融循环之后的各级含水率重塑黄土仍具有二次湿陷性;冻融循环作用下高含水率的土体结构比低含水率的土体结构破坏的较早;干密度一定时,低含水率的土体冻融循环之后的净变形量越大,湿陷系数越小,冻融循环之后的净变形量越小,湿陷系数越大。

英文摘要：

Loess is usually used as the mainbuilding materials for road subgrade. Thecollapsibility can be greatlyeliminated aftercompaction ofcollapsible loess, and it cansatisfy the requirements of whole intensity andstability of road subgrade. However,alot ofdisasters such asdifferential settlement andcollapse occur after the road subgrade of loess has been used for several years inseasonally frozen soil zone.In order toanalyzetheinfluence of various levels ofmoisture contentson collapsibility of loess underfreeze-thaw cycles, deformation andcollapsibility ofcollapsible loess are studied under different freeze-thaw cycles inlaboratory. The test resultsindicate that theremolded loess at every level ofmoisture content still has secondarycollapsibility afterfreeze-thaw cycles. The soil structure with highermoisture content is damagedearlier than that with lowermoisture content underfreeze-thaw cycles. When thedry density is certain, the larger the net amount of deformation with low soil moisture content after freeze-thaw cycles is, the smaller the collapsible coefficient is,and vice versa.