斜向旋喷桩加固重载铁路路基效果研究

Research on reinforcement effect of Shuo-Huang heavy-haul railway subgrade by inclined jet grouting piles

以斜向旋喷桩加固朔黄重载铁路路基为工程背景,运用ABAQUS软件建立三维有限元模型,对比分析均布荷载作用下斜向旋喷桩加固路基前后路基内附加应力分布、路基面沉降的变化规律。研究结果表明:斜向旋喷桩加固路基后,在桩-土交界区域存在应力集中现象,尤其在桩底区域应力集中现象最明显。斜向旋喷桩加固后沿横截面方向不同位置处的附加应力值均较加固前降低,应力分布更加均匀,斜向旋喷桩具有明显的支撑加筋作用。斜向旋喷桩加固后,路基面各位置沉降值明显降低,斜向旋喷桩对降低静荷载作用下路基面的沉降具有积极作用。研究结果为进一步揭示斜向旋喷桩加固效果和朔黄重载铁路扩能改造工程提供参考。

Based on the subgrade of Shuo-Huang heavy-haul railway reinforced by Inclined Jet Grouting Piles(IJGP),a three-dimensional finite element model of reinforced subgrade was established by using ABAQUS software.The change regularity of additional stress distribution in subgrade and settlements of subgrade surface under uniformly distributed load before and after reinforced subgrade by IJGP were analyzed.The results show that stress concentration occurred in pile soil contact areas after reinforced subgrade by IJGP,and this phenomenon was most obvious in the pile bottom.After reinforcing subgrade by IJGP,the additional stresses at different locations along the transverse direction decreases and the distribution of additional stresses becomes more uniform,therefore IJGP has obvious function of supporting and reinforcement.The settlements at different locations of subgrade surface decreases significantly after reinforcing subgrade by IJGP,hence IJGP has positive effect on reducing settlements of subgrade surface.The research results provide reference for further revealing reinforcement effect of IJGP and capacity enlargement of Shuo-Huang heavy-haul railway.