摘要
目前的隧道管棚计算方法和理论解析存在计算繁杂,计算参数的选择对分析结果的正确性影响较大且无法获得精确的理论解或简化的计算公式等问题。文章基于Winkler弹性地基梁理论,考虑隧道施工过程中围岩扰动特性、支护未封闭不完全承载特性、地层反力系数差异特性及荷载分布不均匀特性,建立了管棚超前预支护变形理论计算模型,并通过求解24阶方程组获得超前管棚预支护理论解析。结果表明:1)解析解与数值解和现场实测值吻合度较高,解析解可用于管棚变形预测;2)管棚直径、开挖进尺、地层反力系数均存在最优参数取值,环向间距与管棚变形呈正比例关系,管棚长度并非越长越好,只需满足管棚远端超前掌子面前方2倍台阶高度即可;3)实际施工过程中,通过调整管棚参数来控制隧道拱顶沉降效果从优到劣的顺序为:开挖进尺、注浆改善地层力学性质、环向间距、直径、长度。
In view of the complexities of existing calculation methods and theories for tunnel pipe roof,effects of calculation parameters on analysis results and difficulties to obtain accurate theoretical solution or simplified calculation formula,a theoretical calculation model for predicting deformation of pipe roof as pre-support was established based on Winkler elastic foundation beam theory and considering the disturbance characteristics of surrounding rock,incomplete load bearing behavior due to unclosed support,differences of strata reaction coefficients and uneven load distribution,and a theoretical solution was obtained by solving 24 order equations.The results show that:(1)The analytical solution agrees well with numerical simulation value and field data,and it can be used to predict deformation of pipe roof;(2)it is available to have the optimal parameters of diameter,advance rate and strata reaction coefficient of pipe roof,the circumferential spacing is directly proportional to pipe roof deformation,it meets the requirement only if the length of pipe roof at the far end is not less than two times of the bench height in front of working face;(3)The sequences of controlling effect of vault settlement by adjusting pipe parameters are advance rate,strata mechanical behavior improvement by grouting,circumferential spacing,diameter and length in the order from good to bad.
作者
王道远
袁金秀
王记平
王凯
夏勇
王海蛟
温明
WANG Daoyuan;YUAN Jinxiu;WANG Jiping;WANG Kai;XIA Yong;WANG Haijiao;WEN Ming(Department of Civil Engineering,Hebei Jiaotong Vocational and Technical College,Shijiazhuang 050091;Key Laboratory of Trans?portation Tunnel Engineering of Ministry of Education,Southwest Jiaotong University,Chengdu 610031;School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043;CSCEC Road and Bridge Group Co.,Ltd,Shijiazhuang 050001)
出处
《现代隧道技术》
EI
CSCD
北大核心
2019年第1期79-86,共8页
Modern Tunnelling Technology
基金
国家自然科学基金资助项目(51478277)
河北省自然科学基金资助项目(E201619002)
河北省重点研发计划项目(172776471)
河北省人才工程培养经费资助科研项目(A201500116)
河北省高等学校科学技术研究青年基金(QN2016240)
关键词
浅埋
软弱围岩
隧道
施工过程
WINKLER
管棚
变形预测
参数敏感性
Shallow-buried depth
Weak surrounding rock
Tunnel
Construction process
Winkler
Pipe roof
Deformation prediction
Parameter sensitivity
