摘要
在北京地铁5号线北新桥-雍和宫左线区间隧道试验段，选取3个不同地质情况的测试断面，进行盾构施工过程中管片内力研究。结果表明，在盾构施工过程中，从管片结构形成局部稳定状态到最终与地层之间形成平衡状态，管片的内力不断调整、变化；管片在尾板保护范围之内时，管片在左右45。方位和拱底处轴力较大；管片脱离尾板保护后，土体和填充浆液对管片产生作用，使管片内力迅速增加，增幅最大达30％～40％，此时是装配式管片单层衬砌安全的关键时刻之一；地质情况对管片轴力有较大影响，在粉土层中管片轴力大，在砂土和卵石地层中管片轴力较小；地质情况对管片弯矩的影响不明显；注浆效果对脱离尾板保护管片的内力有直接影响，提高注浆效果可使管片受力均匀，提高管片的耐久性。
In the section of Beixinqiao-Yonghegong left line of Beijing metro line 5, three test sections with different geological conditions were chosen to study the segment internal force during the construction of shield tunnel. Results show that, during the construction of shield tunnel, the segment internal force has been constantly changing and adjusting from the local stability state of the segment structure to the eventual balance between the formation and the structure. When the segments are in the scope protected by the tail-board, the axial force of the segment is larger in the azimuth about 45° or the arch bottom. After the segment is out of the protection of the tail-board, the soil mass and the filling slurry will generate the func- tion to the segment, which makes the segment internal force increase rapidly, and the maximum increase amplitude is around 30%-40%. This is one of the key moments for the safe single-layer lining of the assembling segments. Geological conditions have great influence on the axial force of the segment. The axial force of the segment is larger in silty soil layers, while the axial force of the segment is smaller in sand and gravel layers. The influence of the geological conditions on the bending moment of the segment is not obvious. The grouting has a direct impact on the internal force of the segment out of protection of the tailboard. Improving the grouting effect can make the segment stress uniform and increase the durability of the segment.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2009年第3期57-62,共6页
China Railway Science
基金
高等学校博士学科点专项科研基金资助项目(20050004010)
关键词
管片内力
盾构隧道
施工过程
地下铁道
Segment internal force
Shield tunnel
Construction process
Metro
