甬江沉管隧道长期沉降监测数据及有限元分析

发布时间：2018-09-18 20:39

【摘要】：甬江沉管隧道位于甬江下游河湾处的软土地基上,地基承载力较低,使隧道发生了较大的沉降。此外,甬江严重的淤积及每天2.67 m的潮差对隧道的沉降产生了显著的影响。依据甬江沉管隧道运营期间16 a的沉降监测数据,结合地层条件、潮汐和清淤资料,对该条沉管隧道的长期沉降进行了分析,并提出了基于流-固耦合理论的有限元方法计算沉管隧道的长期沉降,计算结果与监测结果具有较好的一致性。此外,采用上述计算方法分析了影响沉管隧道沉降的3个主要因素(即地层条件、基槽淤积和回淤与清淤)对隧道运营期沉降的影响。分析表明,地层条件是影响沉管隧道沉降的主要因素,软土地基隧道沉降远大于其他地基。潮汐作用会使隧道沉降发生周期性变化,该变化约占隧道运营期沉降的4%~10%。淤积对隧道长期沉降影响显著,但定期清淤只能短时间减小隧道的沉降,使隧道沉降产生周期性变化。上述结论均可为相关工程提供参考。
[Abstract]:The submersible tunnel of Yongjiang River is located on the soft soil foundation of the lower reaches of the Yongjiang River, and the bearing capacity of the foundation is relatively low, which makes the tunnel have a large settlement. In addition, the serious deposition of Yongjiang River and the tidal range of 2.67 m per day have a significant effect on the settlement of the tunnel. Based on the settlement monitoring data of Yongjiang immersed tube tunnel during operation for 16 years, combined with formation conditions, tidal and silt clearing data, the long-term settlement of this tunnel is analyzed. A finite element method based on fluid-solid coupling theory is proposed to calculate the long-term settlement of immersed tunnel. The calculated results are in good agreement with the monitoring results. In addition, the above calculation method is used to analyze the influence of three main factors (i.e. stratum condition, base channel siltation, silting and desilting) on the settlement of the tunnel during the operation period. The analysis shows that the stratum condition is the main factor that affects the settlement of the immersed tunnel, and the settlement of the soft ground tunnel is much larger than that of the other foundations. Tidal action will make the tunnel settlement change periodically, which accounts for about 410 percent of the tunnel settlement during the operation period. Silting has a significant effect on the long-term settlement of the tunnel, but periodic silt clearing can only reduce the settlement of the tunnel in a short time, which makes the settlement of the tunnel change periodically. The above conclusions can provide reference for related projects.
【作者单位】：同济大学岩土及地下工程教育部重点实验室;同济大学地下建筑与工程系;甬江隧道管理处;
【基金】：国家重点基础研究发展(973)计划资助(No.2011CB013800) 国家自然基金项目资助(No.41372273) 上海市科学技术委员会计划资助(No.12231200900,No.13231200102)
【分类号】：U456.3;U459.5

【相似文献】