关键词: 冻融循环, 工程性质, 土体结构, 物理性质, 力学性质

Abstract:

Freeze-thaw cycle effect is one of the most important reasons that cause engineering problems in cold zone. Freeze-thaw cycles may lead to great changes of soil engineering properties, and subsequently cause unacceptable deformation or failure of engineering facilities. The research achievements of the soil engineering change caused by freeze-thaw cycles were analyzed and summarized from structure, basic physical properties and mechanical properties of soil. After freeze-thaw cycles, initial soil fabric was destroyed and reformed, in which clayey aggregates experienced fragmentation and recombination and formed a more uniform structure. Under different internal and external conditions, soil may form different structure. After the action of freezethaw cycle, the permeability of soil increases, plastic index decreases, porosity and density of loose and dense soils have different change trend. Soil mechanics properties show different trends in various test results. On one hand it is relate to the changes of soil structure, and on another hand different method of freeze-thaw cycle test can lead to different research results. Therefore, we need to establish the method of judgments, evaluation and prediction system for variation of soil engineering properties under the freezethaw cycle effect, which can be become the direction of future research work.

Key words: freeze-thaw cycle, engineering property, soil structure, physical property, mechanical property