论文部分内容阅读
上海地铁10号线同济大学站—国权路站双线盾构长距离平行穿越下立交深基坑,穿越距离为630m,隧道与下立交基坑围护净距约2.0m,与下立交底板底的距离为6.1~9.3m,施工现场环境复杂,盾构施工可能导致下立交深基坑底板发生竖向位移并产生附加内力。本文采用三维数值方法,模拟分析在基坑底板浇筑完成的情况下,盾构施工对基坑底板沉降及内力的影响。分析表明:随着围护结构深度的增加,底板横轴绝对沉降量和相对沉降量均逐渐减小,底板纵轴沉降量逐渐减小,基坑底板横轴弯矩逐渐增大,基坑底板纵轴弯矩变化值基本一致;随着盾构的推进,基坑底板先下部受拉、上部受压,随着同步注浆的进行,基坑底板下部受压、上部受拉。数值计算较好地指导了实际工程的施工。
Shanghai Metro Line 10 Tongji University Station - Guoquan Road double-line shield long distance parallel to pass through the intersection of the next deep foundation pit, the crossing distance of 630m, the tunnel and the underpass confined clearance of about 2.0m, and the next interchange floor The distance from the bottom is 6.1 ~ 9.3m. The construction site environment is complex. The shield construction may cause the vertical displacement of the deep foundation pit under the interchange and generate additional internal forces. In this paper, three-dimensional numerical method is used to simulate and analyze the influence of shield construction on the settlement and internal force of foundation floor under the condition that the floor of foundation pit is completed. The analysis shows that with the increase of the depth of the retaining structure, the absolute settlement and the relative settlement of the horizontal axis of the bottom slab decrease gradually, the settlement of the vertical slab of the bottom slab decreases gradually, the bending moment of the bottom slab of the foundation pit increases gradually, With the advancement of the shield, the lower part of the bottom of the foundation pit is tensioned and the upper part is compressed. As the synchronous grouting progresses, the bottom of the foundation pit is compressed and the upper part is pulled. Numerical calculation is a good guide to the actual construction of the project.