基于衬砌长期渗漏水影响的隧道施工扰动诱发超孔隙水压消散及地层固结沉降解

基于Terzaghi-Rendulic固结理论,采用保角映射和分离变量法,计算得到隧道衬砌半渗透漏水边界条件下,盾构施工扰动引起的隧道周围土体超孔隙水压力消散解和地表土体固结沉降,通过工程实例进行验证,发现理论方法与实测数据趋势一致;此外,利用参数分析获得了土体固结沉降和超孔隙水压力的分布影响规律。结果表明:衬砌与土体的相对渗透比越大,固结沉降的初始速率越大,但不影响最终收敛值;土体弹性模量越小,最终固结沉降量越大;土体中超孔隙水压力随着时间增加,在隧道开挖后较短时间里以较大幅度逐渐消散,消散到约为初始值的1/10时减幅放缓;距离衬砌外壁越远,土体初始超孔隙水压力越小,其消散速度也越慢。

Analytical solution for dissipation of excess pore water pressure and soil consolidation settlement induced by tunneling under the influence of long-term leakage

ZHANG Zhi-guo;HUANG Mao-song;YANG Xuan(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;State Key Laboratory for Track Technology of High-speed Railway,China Academy of Railway Sciences,Beijing 100081,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China)