拱北隧道管幕冻结法现场原型试验解冻温度场实测研究

摘要

Authors carried out an in-situ prototype test and focused on the thawing process and temperature field variations both by naturally thawing and "naturally+enforced" thawing.The results showed that the time of both modes was shorter than that of other conventional freezing applications since the volume of the frozen soil was small.Hence,the enforced thawing by brine at ordinary temperature achieved some good results.What is more,after releasing the thermal insulation curtain in the holly pipe,the thawing rate was high enough so that the enhancing tubes could be turn off.As an important part of the research on the freezing effect of FSPR,this test is the first time to study the thawing rules,which is essential for the subsequent construction.%为了能够更加全面地掌握解冻阶段温度场变化规律,采用现场原型试验研究了在解冻阶段两种不同解冻方式(自然解冻和“自然+强制”解冻)下温度场变化规律.试验表明,由于冻土量较小,解冻时间相比于一般冻结工程来说较短,而且利用常温盐水强制解冻,就能达到很好的效果.在空顶管的防通风措施解除后,自然解冻条件下冻土融化速率较快,不需要开启加强管的热盐水循环.该试验作为系统研究管幕冻结法冻结效果动态控制研究的重要一环,探究了管幕冻结法解冻规律,为实际施工提供了可靠的研究依据,能够有效地降低融沉影响.