摘要
在深厚淤泥地层进行拔桩施工易引发地层位移及沉降,严重影响邻近桥梁等基础设施的稳定性和安全性。以广东沿海地区某城际轨道交通项目为依托,通过现场监测、土压力理论及力学分析相结合的方法,深入探讨拔桩施工过程中地层变形的力学机制。研究发现,拔桩后浇筑回填材料在硬化之前,孔内外压力差过大是导致地层塑性流动和侧向变形的主要原因,即便在钢护筒护壁的条件下,提升护筒施工间隙的地层变形仍会引起邻近桩基偏移和桥梁结构的安全隐患。为减少地层扰动,提出泥浆注入法改善孔内外压力差,并对拔桩施工工艺流程进行优化。实验和监测结果表明,改进后的施工工艺有效控制了地层扰动,提升了施工安全性。研究成果可为深厚软土地区的拔桩施工提供科学指导,对保障桥梁工程的长期安全和稳定具有重要意义。
Pile pulling construction in deep silt formations often induces ground displacement and settlement,significantly impacting the stability and safety of adjacent infrastructures,particularly bridge foundations.This study,based on an intercity rail transit project along the coastal region of Guangdong,combines in-situ monitoring,soil pressure theory,and mechanical analysis to explore the mechanisms of ground deformation during pile pulling construction.The findings indicate that the excessive pressure differential between the inside and outside of the borehole,prior to the hardening of backfill material,is a primary factor contributing to plastic flow and lateral deformation.Even with the protection of steel casing,lifting the casing during construction creates gaps that lead to ground deformation,which poses lateral displacement of nearby piles and a safety risk to bridge structures.To mitigate ground disturbance,this paper proposes a mud injection technique to balance the pressure inside and outside the borehole and optimizes the pile pulling construction process.Experimental and monitoring results confirm that the improved construction method effectively controls ground disturbance,enhancing the construction safety.The findings provide scientific guidance for optimizing pile extraction procedures in deep soft soil regions,with substantial implications for ensuring the long-term stability and safety of bridge engineering projects.
作者
彭澍
PENG Shu(China Railway 18th Bureau Group Co.Ltd.,Tianjin 300222,China)
出处
《铁道建筑技术》
2025年第6期208-213,共6页
Railway Construction Technology
基金
中铁十八局集团有限公司科技研究开发计划项目(CR18GK-24-S-p-14)。
关键词
深厚淤泥地层
拔桩施工
桥梁桩基
偏位
工艺优化
deep silt formations
pile pulling construction
bridge pile foundation
lateral displacement
process optimization
