摘要
基于济南轨道交通R1线工程小半径曲线盾构隧道下穿京沪高铁,采取数值模拟手段研究隔离桩桩长、桩间距等不同设置参数下,对既有高铁桥梁结构的保护效果。计算结果表明:增加隔离桩桩长可以提高保护效果,反之降低;隔离桩桩间距增加,保护效果有所降低。通过计算分析,隔离桩采用桩间距1.2 m、桩长39 m(桩端位于隧道底部以下4 m)较为合理。采用室内模型试验针对桩间距1.2 m、桩长39 m隔离桩设计方案进行验证,试验结果表明:盾构隧道所下穿的两侧承台沉降变形均较小,承台沉降最大值仅0.5 mm,隔离桩设置可有效减少盾构施工对高铁桥桩影响。现场全自动化监测结果显示,承台沉降及水平位移的最大值均未超过0.4 mm,小于控制值1.0 mm。现场监测结果与数值模拟、模型试验结果比较一致,验证了数值模拟和室内模型实验结果的可靠性。
The numerical simulation method is used to study the protection effect of the isolation pile on the existing high-speed railway bridge structure under different setting parameters such as pile length and pile spacing based on the small radius curve shield tunnel on Ji’nan Rail Transit R1 line engineering underpassing the Beijing-Shanghai High-speed Railway. The calculation results show that increasing the length of the isolated pile can improve the protection effect, and vice versa. When the spacing of the isolated piles increases, the protection effect is reduced. According to the calculation analysis, it can be seen that the isolation piles are more reasonable with 1.2 m pile spacing and 39 m pile length. Model tests are conducted to verify the design of reasonable isolation piles. The test results show that settlement deformation of both sides of the shield tunnel is small and the maximum settlement of the cap is only 0.5 mm. The isolation pile setting can effectively reduce the influence of shield construction on high-speed railway piles. The results of on-site fully automated monitoring show that the maximum deformation values of each observation target do not exceed 0.4 mm and are less than the control value of 1.0 mm. The on-site monitoring results are consistent with the numerical simulation and model test results, which verifies the reliability of numerical simulation and indoor model experimental results.
作者
吴镇
张秀山
王磊
WU Zhen;ZHANG Xiushan;WANG Lei(Jinan Design Institute,China Railway Engineering Design and Consulting Group Co.,Ltd.,Jinan 250022,China)
出处
《铁道标准设计》
北大核心
2020年第9期88-94,共7页
Railway Standard Design
基金
中铁工程设计咨询集团有限公司科技研究开发计划项目(研2015-23)。
关键词
城市轨道交通
小半径曲线
盾构隧道
隔离桩
下穿
京沪高铁
桥梁
urban rail transit
small radius curve
shield tunnel
isolation pile
underpassing
Beijing-Shanghai High-speed Railway
bridge
作者简介
吴镇(1988—),男,工程师,2013年毕业于石家庄铁道大学道路与铁道工程专业,工学硕士,主要从事地下工程设计与研究工作,E-mail:2582041348@qq.com。
