Multiple Segmented Control Grouting of Steel Flower Pipes in Highway Soft Subgrade Reinforcement Application
In response to the characteristics of soft subgrade,including high compressibility,large po-rosity,high natural water content,low shear strength,and susceptibility to post-construction settle-ment,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 rein-forcement project on the K28+120 to K28+700 section of the Chaozhou-Huizhou Expressway.Nu-merical 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 sub-grade 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 me-ters,the synergistic effect between the pipes weakened.A transverse spacing of 1.0 meter significant-ly 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 settle-ment of the reinforced subgrade had stabilized,with noticeable control over settlement,offering valu-able insights for similar projects.
highwaymulti-stage control grouting steel pipenumerical analysisdeep soft subgrade
万方数据
维普
