管线开挖条件下的复合地基处理技术研究

Research on Composite Foundation Treatment Technology under Pipeline Excavation Conditions

摘要:

城市市政道路建设中，地下管线敷设与不良路基复合地基加固常存在空间冲突，管线反挖施工易破坏桩体结构、影响路基承载性能，同时引发造价管控与施工效率难题。为解决该工程痛点，结合复合地基与管线沟槽开挖梳理了先桩后挖法、挖后打桩法、局部空桩法三种施工工艺的作用机理，分析管线开挖对刚性桩、柔性桩承载性能的影响规律，并建立投资测算模型对比三类方案的投资差异，研究成果可为市政道路不良路基处理与管线施工的时序优化、方案比选提供理论依据与技术参考。

Abstract:

In the construction of urban municipal roads, spatial conflicts often occur between underground pipeline laying and composite foundation reinforcement for poor subgrades. The reverse excavation of pipelines tends to damage the pile structure, impair the bearing capacity of the subgrade, and simultaneously give rise to challenges in cost control and construction efficiency. To address these engineering pain points, the working mechanisms of three construction technologies, namely excavation after piling, piling after excavation and local empty pile method, are sorted out in combination with composite foundation and pipeline trench excavation. The influence laws of pipeline excavation on the bearing performance of rigid piles and flexible piles are analyzed, and an investment calculation model is established to compare the investment differences of the three schemes. The research results can provide a theoretical basis and technical reference for the treatment of poor subgrades of municipal roads, as well as the timing optimization and scheme comparison of pipeline construction.