季节冻土区堤防原位监测与数值模拟分析

Initial position monitoring and numberical simulation analysis of embankment in seasonal frozen soil region

为研究季节冻土区黑龙江干流堤防在一个冻融循环内的土体结构变化情况,通过分析现场埋设的原位监测仪器数据,分别讨论了堤防土体内部温度分布、含水率、土压力的变化情况,然后基于实测数据对堤防整体进行数值模拟分析。得到主要结论如下:(1)在堤防建成后的一个冻融循环内,堤顶下部的冻土深度达到3 m,不同深度处的温度变化有延迟现象;(2)堤防土体内部温度场分布未达到完全稳定,表现出堤身内部分区域高于其附近土体温度的现象;(3)堤防整体位移沉降均匀,外界温度变化对堤防位移有一定影响,堤顶公路部分的相对沉降位移能够准确反映出冻胀融沉现象,但堤防土体的结构变化对其产生的冻融破坏较小。

In order to study the changes of soil structure witli a freeze-tliaw cycle of an embankment of Heilongjiang river’the temperature distribution’water content and soil pressure inside the embankment soil were discussed respectively’through the analysis of tlie initial position monitoring^data on site.Then the numerical simulation of the embankment is carried out based on measured data.Research conclusions as follows:①In a freeze-tiiaw cycle after the completion of tlie embankment’the depth of tlie frozen soil below the embankment there is a delay in the temperature change at different depths;②The distribution of the temperature embankment is not completely stable’showing that the temperature of the part of the embankment is higher than that of other soil;③The displacement of the embankment changes evenly and the external temperature changes have a certain influence on displacement’and the relative settlement displacement of the road on embankment can accurately reflect the phenomenon of freeze-thaw’but the structural changes of the embankment soil have less freeze-tiiaw damage to the road.