摘要
结合两个纯土钉墙工程实例,根据工程失稳时新开挖土层的不同失稳现象,提出了土钉墙施工失稳有超挖失稳和局压失稳两种类型。超挖失稳是由于施工超挖或在上层土钉及坡面还未发生效应即开始开挖下层土方而引起,局压失稳是由于下部新开挖的土体受到上部土体较大局压而失稳。对于超挖失稳,可采用削坡压脚或袋装土回填措施加固。对于局压失稳,除应在土钉墙下部采取加固措施外,必须在上部采取增加预应力锚索以控制变形的措施。
Overbreak excavation instability and local instability are indicated on the phase of construction about soil nail wall on the base of different instability situation about two cases,when excavation beginning.Overbreak excavation instability occur if excavation exceed the design deep,and when the top soil nail and slope don't work effectively,and then to excavate the underlayer.Local instability occur if underlayer is locally stressed by the top soil because of excavation.For overbreak excavation instability,the reinforcement measures are presented to treat by cutting the slope and backfill the soi in bag.For local instability,pre-stressed anchor rope should be added to control the deformation at the top of the soill nail wall with the exception of reinforcement measures at the bottom.
出处
《施工技术》
CAS
北大核心
2008年第S1期90-92,共3页
Construction Technology
基金
湖南省安全生产监督管理局2007年度安全生产科技发展计划项目"基于应力应变监测的深基坑支护结构动态优化设计(07-30)"
关键词
土钉墙
超挖失稳
弹性地基
局压失稳
soil nailing wall
overbreak excavation instability
elastic subgrade
local instability