石灰桩处理岛状冻土地基试验研究  

Experimental Study on Treatment of Patchy Permafrost Foundation with Quicklime Piles

作　　者：程佳 熊治文 金兰 蔡汉成 孟进宝 CHENG Jia;XIONG Zhiwen;JIN Lan;CAI Hancheng;MENG Jinbao(Northwest Research Institute Co. Ltd. of C.R.E.C,Lanzhou Gansu 730000 China;Qinghai Province Key Laboratory of Permafrost and Environmental Engineering,Golmud Qinghai 816000,China)

机构地区：[1]中铁西北科学研究院有限公司,甘肃兰州730000 [2]青海省冻土与环境工程重点实验室,青海格尔木816000

出　　处：《铁道建筑》2019年第9期88-92,共5页Railway Engineering

基　　金：中铁科学研究院有限公司科技开发计划(2017-KJ007-Z007-XB);中国中铁股份有限公司科技开发计划(2016-重大-01)

摘　　要：针对冻土上限较深的岛状多年冻土地基稳定性问题,本文提出了一种用石灰桩预融处理岛状冻土地基的方法。根据生石灰水化反应放热的特点,提出用石灰桩处理高温岛状冻土地基的桩体材料配合比计算公式,并开展了石灰桩模型试验。结果表明,石灰桩能有效融化多年冻土并对融化后的地基土起到挤密加固作用。保证石灰桩预融效果的3个关键要素是:桩体含水率应控制在15%~19%;从拌和到分层夯填完成时间须控制在5 min以内;生石灰粒径宜控制在6 cm以内。Aiming at the stability problem of the patchy permafrost foundation with significant upper limit,a new method is put forward by using quicklime pile. Based on the exothermic reaction of quicklime and water,an equation of pile mixture was proposed for the treatment of high-thermal patchy permafrost foundation with quicklime piles. Also, model test for the quicklime pile was conducted. The results show that the permafrost may be melt effectively due to the quicklime piles,and the melt permafrost foundation is compacted and reinforced. The three keys to the effectiveness of the quicklime pile pre-melting are as follows. First,the water content of pile shall be kept 15%~ 19%. Second,the time from mixing to tamping shall be kept within 5 min. Third,the particle diameter of quicklime shall be smaller than 6 cm.

关 键 词：岛状冻土地基 预融技术 模型试验 石灰桩配比 桩体含水率 

分 类 号：TU44[建筑科学—岩土工程]