宁波地铁1号线高流变软土地层盾构掘进参数分析

Analysis of Shield Driving Parameters for High Rheological Soft Soil on Ningbo Metro Line 1

对宁波地铁1号线海晏北路站—福庆北路站区间盾构施工进行三维有限元建模分析,研究盾构机在高流变海相饱和软土地层中掘进时盾尾管片注浆时间、管片注浆压力、上下顶进力差、顶进力、隧道埋深等因素对管片上浮与地表沉降的影响。结果表明:上下顶进力差与管片注浆压力对隧道管片上浮影响最大,盾尾管片注浆时间次之,埋深与顶进力影响最小;上下顶进力差、埋深、盾尾管片注浆时间与管片上浮量呈负相关关系,而顶进力、管片注浆压力与管片上浮量呈正相关关系;盾尾管片注浆时间、管片注浆压力、埋深对地表沉降产生较明显的影响,其次是上下顶进力差,而顶进力的影响较小;上下顶进力差、管片注浆压力、埋深与地表沉降量呈正相关关系,仅盾尾管片注浆时间与地表沉降量呈负相关关系。

Interval shield construction of H aiyan north road station to Fuqing north road station in N ingbo Metro Line 1 was modeled and analyzed by three-dimensional finite element,and the effects of segmental lining grouting time at the tail,grouting pressure,jacking force difference between top and bottom,jacking force and tunnel buried depth on segmental lining floating and surface settlement was studied during shield machine excavation in the high rheological marine saturated soft soil stratum. The results showed that jacking force difference between top and bottomand segmental lining grouting pressure has the largest influence on segmental lining floating,followed by the effect of segmental lining grouting time at the tail,and jacking force and tunnel buried depth has the least effect,jacking force difference between top and bottom,tunnel buried depth and segmental lining grouting time at the tail has a negative correlation with the amount of segmental lining floating,jacking force,segmental lining grouting force has a positive correlation with the amount of segmental lining floating,segmental lining grouting time at the tail,segmental lining grouting force and tunnel buried depth has a obvious effect on surface settlement,followed by jacking force difference between top and bottom,and effect of jacking force is small,the jacking force difference between top and bottom,segmental lining grouting force,tunnel buried depth has a positive correlation with the amount of surface settlement,and only the segmental lining grouting time at the tail has a negative correlation with the amount of surface settlement.