摘要
地铁隧道盾构下穿保护建筑群施工中,如何准确预测和合理控制诱发的地面沉降是亟待解决的难题。文章结合某超大直径盾构下穿保护建筑群施工实践,基于地层损失,利用经验-解析法建立了地面沉降和地层损失率的关系;利用Peck公式分析不同地层损失率下地面沉降以及不同距离、不同地层损失率对应的沉降值大小,再利用Attewell公式和刘建航公式对盾构推进至始发井前方不同距离处不同地层损失率下,以及通常地层损失率下盾构推进至不同位置处的地面纵向沉降进行了研究分析,并将其与监测数据进行了对比。结果表明,监测数据与解析计算结果吻合较好;盾构推进诱发的地面沉降最大值均位于隧道中轴线处,最大沉降量随着地层损失率的增大而增大;在相同的地层损失率下,距离隧道轴线越远的位置,盾构推进诱发的地面沉降越小。
The prediction of ground settlement induced by a shield passing under sensitive buildings is an ur- gent problem to be solved in shield construction. Using the construction of an extra-large diameter shield passing under sensitive buildings as an example, and based on ground loss theory, a relationship between ground settle- ment and the ground loss ratio is established by the empirical-analytic method. The ground settlements under dif- ferent ground loss ratios and the magnitudes of settlement under different distances to the center line and differ- ent ground loss ratios are calculated with the Peck formula. Additionally, using the Attewell formula and the Liu Jianhang formula, tile longitudinal ground settlements under different driving distances and different ground loss ratios, as well as the longitudinal ground settlements under different driving distances and the common ground loss ratio, are calculated respectively. The calculation results are verified in comparison with the measured ones. The results show that the empirical-analytic model can accurately predict ground settlement; all the maximum ground settlements induced by shield driving just emerge at the tunnel central axis, increasing with the increment of ground loss ratio; and under the same ground loss ratio, the further the distance from the tunnel axis, the small- er the ground settlement is.
出处
《现代隧道技术》
EI
北大核心
2013年第5期98-104,共7页
Modern Tunnelling Technology
基金
国家自然科学基金(41072205)
上海市自然科学基金(10ZR1431500)
关键词
盾构下穿施工
地面沉降
地层损失
保护建筑群
Underneath shield construction
Ground settlement
Ground loss
Sensitive buildings