摘要
以正在建设的上海市北横通道Ⅱ标段超大直径盾构隧道为研究背景,对地表沉降的大量监测数据进行分析,研究了超大直径盾构隧道在浅覆土施工工况与急曲线施工工况下的地表沉降规律,分析了掘进参数对沉降的影响。研究结果表明,浅覆土工况地表容易受到扰动,变形对施工参数的变化更加敏感,最大隆起可达10.5 mm,最大沉降为-18.7 mm;在隧道急曲线段存在盾构超挖,可能导致地表沉降增大,最终沉降量可达-12.6 mm,通过提高注浆填充率至120%以上,可控制最终沉降在10 mm以内。根据监测数据分析结果,对不同工况提出了针对性策略,使地表变形得到有效控制,保障施工引起的地层损失率控制在0.1‰~0.3‰。
Taking a super-large diameter TBM tunnel of the Beiheng expressway lotⅡ(BEPⅡ)in Shanghai as a research background,it analyzes a large number of monitoring data of ground surface settlements and the law of ground surface settlements induced by the super-large-diameter TBM under shallow overburden or tight curved alignment,and studies the influence of the TBM parameters on tunnelling.The analysis results indicate that under the shallow overburden condition,the ground surface is easy to be disturbed;the ground deformation is more sensitive to the change of the TBM parameters;the maximum heaving is 10.5 mm and the maximum settlement is 18.7 mm;in the case of tight curved alignment,over-excavation might occur and increase the settlement,with the maximum settlement of 12.6 mm,and the final settlement can be controlled within 10 mm by increasing the grout filling rate to be more than 120%.Based on the analysis results,construction strategies are proposed in light of different construction environments,by which the ground loss ratios can be effectively controlled within the scope of 0.1‰to 0.3‰.
作者
包蓁
BAO Zhen(Shanghai Tunnel Engineering Co.,Ltd.,Shanghai 200082)
出处
《现代隧道技术》
EI
CSCD
北大核心
2020年第S01期394-403,共10页
Modern Tunnelling Technology
关键词
超大直径盾构
急曲线掘进
浅覆土
地表沉降
Super-large diameter TBM
Tight curved tunnelling
Shallow overburden
Ground surface settlement
