粗粒硫酸盐渍土区高速铁路水泥固化级配碎石变形特性  

Deformation characteristics of cement stabilized macadam aggregate of high-speed railway in coarse-grained sulfate soil area

作　　者：张莎莎[1] 刘亚超 杨晓华[1] 李安洪[2] 陈伟志[2] 余泽龙 赵彦虎 ZHANG Sha-sha;LIU Ya-chao;YANG Xiao-hua;LI An-hong;CHEN Wei-zhi;YU Ze-long;ZHAO Yan-hu(School of Highway,Chang'an University,Xi'an 710064,Shaanxi,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,Sichuan,China;School of Civil Engineering and Built Environment,Liverpool John Moores University,Liverpool L33AF,Merseyside,UK)

机构地区：[1]长安大学公路学院,陕西西安710064 [2]中铁二院工程集团有限责任公司,四川成都610031 [3]利物浦约翰摩尔大学土木工程与建筑环境学院,默西塞德利物浦L33AF

出　　处：《交通运输工程学报》2023年第1期93-104,共12页Journal of Traffic and Transportation Engineering

基　　金：国家自然科学基金项目(42101126);陕西省自然科学基础研究计划(2019JM-147);中国中铁股份有限公司科技开发计划(2017-重大-11-04);青海省交通运输厅科技项目(2020-02)。

摘　　要：为了探究粗粒硫酸盐渍土区高速铁路路涵、桥梁等过渡段的水泥固化级配碎石在不同工况下的变形特征及其机理,基于固化路基填料的材料特点,采用0~2.5%含盐量的级配碎石,掺加不同种类及含量的水泥,开展常温下有(无)毛细水上升的变形特性试验;针对固化路基段的基床,开展基础冻融循环模拟试验,同时结合XRD试验分析变形机理;在试验的基础上,选取典型试验材料,开展冻融循环工况下的路基-构筑物模拟试验。试验结果表明:在无毛细水上升工况中,普通水泥配制的含盐级配碎石试样产生的变形可达5%特种水泥掺配试样变形的4.2倍;在有毛细水上升工况中,普通水泥配制试样产生的变形最高可达5%特种水泥掺配试样变形的33.0倍;在不同含盐量条件下,3%~5%特种水泥固化级配碎石对相应普通水泥工况产生变形(毛细水上升导致)的最低抑制率为60%~80%;在6次基础冻融循环条件下,添加普通硅酸盐水泥试样产生的最终变形是添加特种水泥试样最终变形的16.0倍;路基-构筑物冻融循环模拟试验中特种水泥固化级配碎石的最大膨胀变形率仅为0.2%;在粗粒硫酸盐渍土地区,虽然水泥固化路基填料可以减少路基其他变形,但是对于高速铁路等对变形控制要求较严格的工程,周围介质中的盐分因素较难避免,普通水泥无法满足盐渍土地区的路基工程需求,需要采取特种水泥固化等工程措施。To explore the deformation characteristics and mechanisms of cement stabilized macadam aggregate at the culverts,bridges and other transition sections for high-speed railways under different working conditions in coarse-grained sulfate saline soil area,based on the material properties of solidified subgrade filler,the graded gravel with 0-2.5% salt content was used and mixed with different kinds and contents of cements,and the deformation characteristics tests with and without capillary water rising at normal temperature were carried out.Besides,the basic freeze-thaw cycle test of the solidified subgrade bed was performed,and the composition change was analyzed by the XRD test at the same time.Based on the test results,the typical test materials were selected to carry out the subgrade-structure model test subjected to the freeze-thaw cycle.Test results show that without capillary water supply,the deformation of the salt-bearing graded crushed stone sample prepared with ordinary cement can reach 4.2 times that of the sample mixed with 5% special cement.Particularly,with capillary water supply,the deformation of the ordinary cement mixed sample can reach 33.0 times that of the 5% special cement mixed sample.Under different salt contents,the minimum inhibition rate achieved by 3%-5% special cement stabilized graded crushed stone on the deformation reduction of corresponding ordinary cement working condition(caused by capillary water rising) is 60%-80%.Subjected to six basic freeze-thaw cycles,the final deformation of the sample with ordinary cement is 16.0 times that of the sample with high sulfate resistance cement.Under the freeze-thaw cycle condition,the maximum expansion deformation rate of stabilized macadam aggregate mixed with special cement is only 0.2% in subgrade-structure model test.In coarse-grained sulfate saline soil area,although the cement solidified subgrade filler reduces other deformations of subgrade,it is necessary to introduce special cement solidification and other engineering measures for hig

关 键 词：高速铁路 路基工程 固化土 硫酸盐渍土 模拟试验 

分 类 号：U213.1[交通运输工程—道路与铁道工程]