前海湾大直径盾构隧道局部渗流对周边建筑物的影响分析

Influence of Local Seepage of Qianhai Bay Large-diameter Shield Tunnel on Surrounding Buildings

为了研究运营期的大直径盾构隧道局部渗流对周边建筑物产生的影响,依托深圳前海湾大直径盾构隧道项目,基于流固耦合理论,利用ABAQUS有限元软件建立大直径盾构隧道局部渗流的二维实体模型,分别对不同位置的接头渗水进行计算分析。计算结果表明,渗水位置对地表沉降的影响较大,渗水位置越靠近隧道顶部地表,不均匀沉降越明显且最大沉降量越大。因此,渗水位置越靠近隧道顶部时,长期固结沉降导致的周边建筑物倾斜程度越大,越不利于建筑物的稳定性。以倾斜程度作为建筑物破坏等级的评判标准,通过局部渗流引起的地表沉降曲线计算出不同位置处的建筑物的倾斜程度,基于经验判断法,给出建筑物与隧道中心之间最小安全距离的保守估计值。

To study the influence of local seepage of large-diameter shield tunnel on surrounding buildings during operation period,relying on Shenzhen Qianhai Bay large-diameter shield tunnel project and based on fluid-solid coupling theory,ABAQUS is used to establish a two-dimensional solid model of the tunnel and then the seepage position at different joints are calculated and analyzed.The calculation results show that the seepage position has a great influence on the surface settlement of soil.The closer the seepage position is to the top of the tunnel,the more uneven the settlement and the larger the maximum settlement.Therefore,the closer the water seepage position is to the top of the tunnel,the greater the degree of inclination of the surrounding buildings caused by long-term consolidation settlement, and the more unfavorable the stability of the building.The degree of inclination is used as the criterion for determining the degree of damage of buildings.The degree of inclination of buildings at different locations is calculated by the surface settlement curve caused by local seepage,and the conservative estimate of the minimum safety distance between the building and the tunnel center is given based on empirical judgment.