浅埋偏压小净距隧道CD法施工合理净距  

Study on Reasonable Spacing of Shallow-Embedded Biased Neighborhood Tunnel with CD Method Construction

作　　者：毕玉 BI Yu(Huangmaohai Link Management Center,Zhuhai Guangdong China 519055)

机构地区：[1]黄茅海跨海通道管理中心,广东珠海519055

出　　处：《广东公路交通》2022年第6期118-121,143,共5页Guangdong Highway Communications

摘　　要：以某浅埋偏压小净距隧道为背景,利用三维有限差分软件建立不同净距工况的隧道模型,分析不同小净距隧道挖掘后的中夹岩柱周边围岩塑性区范围、相应位移与最大应力变化规律,确定浅埋偏压小净距隧道CD法施工的合理净距,并将监测与模拟数据进行对比分析。结果表明:随着净距增大,中夹岩柱侧下方塑性区范围减小,中夹岩柱右侧水平与竖向位移缓慢增加,中夹岩柱左侧水平与竖向位移逐渐下降,中夹岩柱相应部位最大主应力呈减小的趋势。分析中夹岩柱围岩塑性区、位移与应力,得出CD法施工的合理净距为0.75B。监测与模拟数据误差范围5%~15%,一定程度上论证了数值模拟的可靠性。With a shallow tunnel with small bias distance as the background, FLAC3D software has been used to establish tunnel models with different clear distance conditions. The plastic zone range, corresponding displacement and maximum stress variation rule of the surrounding rock of the middle sandwich-pillar after tunnel excavation with different small bias distance have been analyzed. The reasonable clear distance of shallow tunnel with small bias distance has been determined by CD method, and the monitoring and simulation data have been compared and analyzed. The reasonable clear distance of CD method construction of shallow buried bias small clear distance tunnel has been determined, and the monitoring and simulation data have been compared and analyzed. The results have shown that with the increase of clear distance, the plastic zone range below the side of middle rock pillar decreases, the horizontal and vertical displacement on the right side of middle rock pillar increases slowly, the horizontal and vertical displacement on the left side of middle rock pillar decreases gradually, and the maximum principal stress of middle rock pillar decreases. By analyzing the plastic zone, displacement and stress of surrounding rock with rock pillar, it has been concluded that the reasonable spacing of CD method is 0.75B. The error range of monitoring and simulation data is 5%~15%, which proves the reliability of numerical simulation to some extent.

关 键 词：浅埋偏压小净距隧道 CD法施工 合理净距 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]