长兴岛盾构工作井超深基坑施工风险评估

以上海青草沙原水过江管工程的长兴岛超深基坑为背景,在深入研究工程特点、建设要求、工程地质情况及周边环境的基础上,对本工程项目超深基坑施工过程中的主要风险点进行辨识与分析,并给予风险等级评定,最终结合风险发生机理提出风险控制措施及相应的结论和建议。实际施工和管理过程中,风险管理的理论与方法同具有丰富工程经验的专家意见进行有机结合,并督促施工方将风险控制措施一一落到实处,为青草沙原水过江管工程的隧道施工与后期运营奠定了坚实的基础。其中相关经验可为今后上海长江边类似超深基坑工程施工提供有意义的参考。     

Ф14.93m泥水平衡盾构穿越乙烯管施工技术研究

以虹梅南路~金海路通道西线隧道为工程背景,从切口压力、掘进速度与盾构姿态、盾构推力与刀盘扭矩、注浆压力与注浆量、进排泥流量和泥水指标等参数管理和现场监测等方面,探讨了Ф14.93m泥水平衡盾构穿越Φ273mm乙烯管沉降控制施工技术,为类似工程提供了参考。     

Assessment of ground conditions with respect to mechanised tunnelling for the construction of the extension of the Athens Metro to the city of Piraeus

This paper refers to the proposed western extension of the Athens Metro to Piraeus city. The railway consists of a 9.45 m diameter, 8.2 km long tunnel and seven stations. Tunnelling works are expected to be undertaken within a variety of lithological formations ranging from very strong alpine limestones to recent soft littoral deposits. The tunnel alignment was divided into 12 areas with respect to the geological and geotechnical conditions that may be encountered during construction. In many of these zones, the geotechnical conditions together with the presence of sensitive surface and/or subsurface structures led to the selection of a closed-face TBM (Earth Pressure Balance Machine or Slurry Tunnel Boring Machine) as the appropriate tunnelling technique. The Piraeus extension is a project where in places both types of commonly used closed-face tunnelling machines will encounter ‘text book’ application areas, but not always. The applicability of each type of TBM is discussed using the available data obtained from an extensive site investigation.      

Case studies of TBM tunneling performance in rock–soil interface mixed ground

This paper investigates the performance of tunnel boring machines (TBMs) in rock–soil mixed-face ground based on TBM tunneling projects in Singapore. Currently several methods are available to estimate TBM tunneling performance in homogenous rock or soil. However, the existing models cannot be effectively applied to predict TBM penetration rate in mixed ground. The tunnels in this study were excavated in adverse mixed-face ground conditions. The geological profiles and the TBM operational parameters are compiled and analyzed. The influence of different geological face compositions on the performance of the TBMs is studied. The statistical analysis shows that there is a possible correlation between the mixed-face ground characteristics and the TBM advancement. Different approaches are used to find a reliable model. Finally, a method is proposed to predict the TBM performance in mixed-face ground for project planning and optimization.     

TBM—3^#输送机皮带曲线运行防跑偏方案及实施

简要介绍了用于桃花铺1号隧道施工的TBM在通过隧道进口段曲线时3#胶带输送机运行时存在的问题及其分析,提出了防跑偏的措施和实施方案,可供同类问题借鉴.     

TBM自重对围岩变形影响的数值模拟研究

为研究双护盾全断面隧道掘进机(TBM)自重对围岩变形的影响,基于FLAC3D有限差分软件,通过改变隧道的埋深与围岩条件,建立3种工况数值模型,并对每个工况分别进行了考虑TBM自重与不考虑其自重的数值模拟,以对比各种工况下有无TBM自重作用的隧道围岩纵向位移曲线(LDP曲线);研究了TBM自重对围岩变形的影响。模拟结果表明,TBM自重可抑制隧道围岩的径向位移,并随着开挖隧道的围岩等级升高、埋深变浅,其自重对围岩变形的影响越大,且与不考虑TBM自重的围岩变形相比,边墙洞壁的径向位移减小率最大,仰拱与拱顶次之。这些认识对研究TBM与围岩的相互作用和预测卡机有重要意义。     

Excavation of underground research laboratory ramp in granite using tunnel boring machine: Feasibility study

Underground research laboratory (URL) plays an important role in safe disposal of high-level radioactive waste (HLW). At present, the Xinchang site, located in Gansu Province of China, has been selected as the final site for China’s first URL, named Beishan URL. For this, a preliminary design of the Beishan URL has been proposed, including one spiral ramp, three shafts and two experimental levels. With advantages of fast advancing and limited disturbance to surrounding rock mass, the tunnel boring machine (TBM) method could be one of the excavation methods considered for the URL ramp. This paper introduces the feasibility study on using TBM to excavation of the Beishan URL ramp. The technical challenges for using TBM in Beishan URL are identified on the base of geological condition and specific layout of the spiral ramp. Then, the technical feasibility study on the specific issues, i.e. extremely hard rock mass, high abrasiveness, TBM operation, muck transportation, water drainage and material transportation, is investigated. This study demonstrates that TBM technology is a feasible method for the Beishan URL excavation. The results can also provide a reference for the design and construction of HLW disposal engineering in similar geological conditions. © 2020 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).     

高地应力区双护盾TBM隧道围岩性态即时判示分析

青藏高原及其东缘高山区的交通建设和能源开发,需要修建众多的深埋长大隧道,采用TBM掘进具有显著优势.依托西藏雅鲁藏布大峡谷DXL隧道双护盾TBM掘进施工,就隧址区工程地质环境、基于尾渣的围岩特征信息的即时获取方法以及围岩性态判别等进行了研究.结果表明:(1)高地应力环境下,隧址区裂隙性硬质围岩微细观破裂,造成宏观大变形...     

Real-time prediction of rock mass classification based on TBM operation big data and stacking technique of ensemble learning

Real-time prediction of the rock mass class in front of the tunnel face is essential for the adaptive adjustment of tunnel boring machines(TBMs).During the TBM tunnelling process,a large number of operation data are generated,reflecting the interaction between the TBM system and surrounding rock,and these data can be used to evaluate the rock mass quality.This study proposed a stacking ensemble classifier for the real-time prediction of the rock mass classification using TBM operation data.Based on the Songhua River water conveyance project,a total of 7538 TBM tunnelling cycles and the corresponding rock mass classes are obtained after data preprocessing.Then,through the tree-based feature selection method,10 key TBM operation parameters are selected,and the mean values of the 10 selected features in the stable phase after removing outliers are calculated as the inputs of classifiers.The preprocessed data are randomly divided into the training set(90%)and test set(10%)using simple random sampling.Besides stacking ensemble classifier,seven individual classifiers are established as the comparison.These classifiers include support vector machine(SVM),k-nearest neighbors(KNN),random forest(RF),gradient boosting decision tree(GBDT),decision tree(DT),logistic regression(LR)and multilayer perceptron(MLP),where the hyper-parameters of each classifier are optimised using the grid search method.The prediction results show that the stacking ensemble classifier has a better performance than individual classifiers,and it shows a more powerful learning and generalisation ability for small and imbalanced samples.Additionally,a relative balance training set is obtained by the synthetic minority oversampling technique(SMOTE),and the influence of sample imbalance on the prediction performance is discussed.     

Ф6．34m土压平衡盾构机三维参数化建模研究

参数化建模是用约束来表达产品模型的形状、大小、位置，产品设计的参数化可极大地提高设计效率。本文介绍了Ф6.34m土压平衡盾构机在Pro/E中的三维参数化建模方法，提出了装配、零件模型的层次化建模方法及策略，在零部件间建立约束关系的方法。为提高土压平衡盾构机的设计效率、盾构机的系列化提供了强力支持。