记笔记

Study on water and salt migration of saline soil under the condition of freeze-thaw cycles

Xu WangMao XuesongTang KeTang Xinlei

School of Highway,Chang’an University

摘要：In order to study the effect of freeze-thaw cycles on the water-salt migration of saline soil subgrade,the saline soil was subjected to zero,three,five,seven and nine times respectively under the conditions of optimum water content and salt content of 2%.The sub-freeze-thaw cycle test was carried out to monitor the change of water and salt,and the test results were compared and analyzed.The results show that with the increase of freeze-thaw cycle times,the water content at each layer height increases and the water channel gradually penetrates.The water content shows a tendency of upper part and small part.The initial state salt is evenly distributed.With the increase of freeze-thaw cycle times and with the boundary of 40 cm,the salt content of the upper part of the soil column shows an increasing trend,and the salt content of the lower part shows a decreasing trend.The salt migration channel begins to form after the three cycles.After the channel is completely formed,the salt in the subgrade gradually migrates from the bottom to the cold end;the freeze-thaw cycle contributes to the formation of water and salt migration channels,and promotes the migration of water and salt.

关键词：

freeze-thaw cycles; saline soil; water; salt; migration;

会议名称：

2019世界交通运输大会

会议时间：

2019-06-13

会议地点：

中国北京