软土路堤填料二次加灰处理技术探讨  

TWO TIMES ADDING QUICKLIME TECHNQIUE FOR IMPROVING SOFT SOIL FILLS AS EXPRESSWAY ROADBEDS

作　　者：崔大伟[1] 阎长虹[2] 夏文俊[1] 张义贵[3] 王智[3] 张睿 董平[2] 郑军[2] 陈明珠[2] 周欣[1] 

机构地区：[1]江苏省高速公路指挥部,南京210004 [2]南京大学地球科学系,南京210093 [3]江苏捷达交通工程集团有限公司,淮安223001 [4]淮安高速公路指挥部,淮安223001

出　　处：《工程地质学报》2008年第4期572-576,共5页Journal of Engineering Geology

基　　金：江苏省交通科学研究计划资助项目(2006-45-3);博士点基金资助项目(20070284006)

摘　　要：目前在江苏高速公路建设中对软土改性处理多采用二次加灰技术,这一处理技术不仅有效解决了软土水分高、土块粉碎困难、掺灰不均、施工速度慢、易造成石灰失效等技术问题,而且可以提高灰土的强度,工程实践表明,其CBR强度可以提高6%～8%。本文就软土改性二次加灰技术的机理作深入探讨,研究表明,第一次加灰,石灰消解既可以吸收土中水分,所产生的热量又可以加快水分蒸发,同时Ca离子随水进入黏土矿物颗粒表面进行离子交换;第二次加灰,通过压实使石灰与软土进一步发生离子交换和火山灰反应,形成新的结晶体和结构,提高灰土的强度和稳定性。A new technique of two times adding quicklime for improving soft - soils was developed and used during Jiangsu expressway construction. It not only settled effectively the problems of soft soil smashed difficulty, gray - doped uneven, and slow construction, and in -effect of quicklime, but also increased the strength of quicklime mixed -soft soils. The test results show that the CBR value of lime -soil mixtures increases by 6% to 8%. This paper examines the mechanism of the technique. At the first time, when it is added to soft soils, the quicklime absorbs the soil moisture and evaporates the soil moisture by the heat of quicklime degradation, and leads to ions exchange. At the second time , when it is further added to the pre - treated soft - soils, the quicklime increases further the volcanic ash and ion exchange, forms new crystals and structure, and subseqyentlv, improves the strength and stability of the lime - soil mixture through the compaction of lime and soft soil.

关 键 词：公路 软土 改性处理 二次添加灰处理技术 

分 类 号：P642.133[天文地球—工程地质学]