多次分段控制注浆钢花管高速公路软基加固应用  

Multiple Segmented Control Grouting of Steel Flower Pipes in Highway Soft Subgrade Reinforcement Application

作　　者：袁坤 YUAN Kun(Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《防灾减灾工程学报》2024年第6期1428-1438,共11页Journal of Disaster Prevention and Mitigation Engineering

基　　金：中国铁道科学研究院集团有限公司青年基金(2022YJ107);中国铁道科学研究院集团有限公司基金重点项目(2023YJ221)资助。

摘　　要：针对软土路基压缩性高、孔隙比大、天然含水率高、抗剪强度较低且工后易沉降等特点,依托潮惠高速公路K28+120~K28+700段软基加固抢险实际工程,提出使用多次分段劈裂注浆竖向钢花管微型桩快速处治技术,采用数值模拟软件建立钢花管加固深厚软土路基数值模型,研究不同桩间距对软基滑移处治效果的影响,结果表明:(1)竖向钢花管具有桩体及抗滑作用,多次分段控制注浆通过劈裂、挤密、置换提高深厚淤泥土的承载力及桩土摩阻力;(2)数值模拟分析表明多次分段控制注浆竖向钢花管纵向间距<1.5 m,钢花管之间的相互协同作用明显,纵向间距>1.5 m,钢花管之间的协同作用相对减弱。横向间距为1.0 m,路基稳定性提高显著,当竖向钢花管横向间距>1.5 m,路基稳定性系数的逐渐趋于平缓;(3)运营期监测结果表明,多次分段控制注浆竖向钢花管加固段的路基沉降基本趋于稳定,控制沉降效果明显,为类似工程整治提供借鉴。In response to the characteristics of soft subgrade,including high compressibility,large porosity,high natural water content,low shear strength,and susceptibility to post-construction settlement,this study proposes a rapid treatment technique using multiple segmented splitting grouting of vertical steel flower pipe micro-piles.The method was applied in an emergency soft subgrade reinforcement project on the K28+120 to K28+700 section of the Chaozhou-Huizhou Expressway.Numerical simulation software was used to establish a numerical model of steel flower pipe reinforcement for deep soft subgrade,studying the impact of different pile spacing on the treatment effect of soft subgrade sliding.The results indicated that:1)The vertical steel flower pipes exhibited both pile body and anti-sliding effects.Multiple segmented grouting improved the bearing capacity and pile-soil friction of deep silt soil through splitting,compaction and replacement.2)Numerical simulations showed that when the longitudinal spacing of vertical steel pipes with multiple segmented grouting was less than 1.5 meters,the synergistic effect between pipes was significant.When the spacing exceeded 1.5 meters,the synergistic effect between the pipes weakened.A transverse spacing of 1.0 meter significantly improved subgrade stability,while spacing greater than 1.5 meters resulted in a gradual levelling off of the stability coefficient.3)Monitoring results during the operational phase indicated that the settlement of the reinforced subgrade had stabilized,with noticeable control over settlement,offering valu-able insights for similar projects.

关 键 词：高速公路 多次分段控制注浆钢花管 数值分析 深厚软基 

分 类 号：U416.1[交通运输工程—道路与铁道工程]