既有下卧地铁条件下平行基坑结构优化研究  

STUDY ON STRUCTURAL OPTIMIZATION OF FOUNDATION PIT ABOVE EXISTING PARALLEL METRO

作　　者：王洋[1] 李晖[1] 

机构地区：[1]上海市政工程设计研究总院(集团)有限公司,上海200092

出　　处：《建筑技术》2017年第9期947-950,共4页Architecture Technology

基　　金：国家自然科学基金资助项目(51278427)

摘　　要：以成都红牌楼既有下卧地铁条件下平行明挖基坑结构工程为依托,建立FLAC3D三维数值力学模型,研究不同控制措施条件下围岩与结构稳定性。研究表明:注浆加固能有效地改善了坑底及既有地铁周围土体的整体刚度,减弱上部基坑开挖对既有地铁结构的影响。抗浮桩及抗浮压梁配合分段预留部分土体施工有利于槽底彻底清渣,且在已建地铁上方与抗浮桩形成了一个类似于保护伞的门式框架结构,从而减弱了对已建地铁结构的不利影响。Taking Hongpailou open-cut foundation pit above existing parallel metro in Chengdu city as an example, three-dimensional modeling utilizing FLAC3D was performed to investigate the stability on account of various measures. Inspection of modelling results reveals that grouting reinforcement can be capable of improving the stiffness of pit bottom and soils around existing metro, and reducing the influence of up foundation excavation on the existing metro structure. The construction associated with anti-floating pile, anti-floating beam as well as excavation by steps can be beneficial to clean thoroughly pit bottom, and form the frame structure of similar unabrella, so that it declines the unfavorable effect on the existing metro.

关 键 词：近接施工 抗浮桩 分步开挖 结构优化 

分 类 号：TU433[建筑科学—岩土工程]