地压平衡法在安庆长江盾构隧道施工中的应用

针对安庆长江盾构隧道工程难点,介绍了地压平衡法在盾构隧道穿越粉细砂地层施工中的应用,分别阐述了接收端渗漏的原因及封堵措施,地压平衡法施工方法和步骤及实施效果,为今后同类工程积累了宝贵经验。     

Large rectangular cross-section tunneling by the multi-micro shield tunneling (MMST) method

The Metropolitan Expressway Public Corporation is planning to construct a 4-lane highway tunnel of rectangular cross-section with a shallow depth below an existing city street which width is approximately equal to the one of tunnel to be newly constructed. A non-cut-and-cover method is required. To achieve this, the multi-micro shield tunneling (MMST) method has been developed. To construct a large cross-section as a whole section of tunnel, first, smaller cross-sections, as units of tunnel, which are located at the circumference of a whole section of tunnel are excavated by shield machines and lined with segments. Secondary, these smaller units are connected and, finally, a tunnel by the MMST method is completed by excavating soil inside connected smaller units which function as a lining of whole section of tunnel (a large cross-section). This paper describes the MMST method and the outline of the shield machine developed to be applied to the MMST method, the construction results of the tunnels and the test implementation.     

盾构隧道衬砌的设计方法分析

针对盾构隧道衬砌管片的内力及变形受多种因素影响的情况,结合工程实例,从衬砌管片方面分析了衬砌的内力及变形,得出衬砌管片的内力及变形随其自身因素变化的一些规律,以供设计人员参考。     

Present status and technology of shield tunneling method in Japan

Recently in Japan, it has often been necessary to construct tunnels under more severe conditions and to develop new techniques. However, present design techniques cannot appropriately reflect the construction techniques; and thus, traditional methods are still often used. On account of the well-balanced progress between construction and design in the shield tunneling method, an innovation of the design technique is required. This paper shows an outline of the shield tunnel technique at present, behavior of shield tunnels in-site, and improvements required for design.     

浅谈盾构法施工对盾构设备的选型

介绍了盾构的分类和适用范围、盾构法施工的优点及盾构机的应用,从选型依据、程序等方面详细阐述了盾构机的选型,并结合上海某地铁盾构施工设备选型进行了说明,以对盾构施工起到指导作用。     

不同施工工况下双圆盾构引起的土体沉降研究

采用随机介质理论,推导出双圆盾构隧道施工时正常工况和旋转工况下由于土体损失引起的土体沉降计算公式。算例分析表明：本文方法地面沉降预测结果与实测值比较吻合;旋转工况下双圆盾构隧道施工引起的土体沉降曲线呈不对称,最大沉降值出现在向下旋转一侧,能较好的解释实测地面沉降曲线不对称的原因。在相同土体损失率时,与正常工况相比,旋转工况产生的最大沉降量变小,但沉降槽宽度变大。两者引起的土体沉降沿深度变化规律也有区别。     

盾构开仓现场气体检测方法的研究

盾构机在掘进过程中要根据地层地质条件以及刀具磨损情况,进行开仓检查或开仓换刀,以防止刀盘结构遭到破坏。盾构土仓内存在的易燃易爆及有毒有害气体直接影响盾构开仓作业人员的健康安全,甚至可能导致缺氧窒息、有毒有害气体中毒及爆炸等恶性事故。结合福建省地铁隧道盾构法施工的实际情况以及福建省地方性标准《盾构法地铁隧道施工现场气体检测规程》的编制情况,本文论述了地铁隧道盾构开仓及气压作业状态下盾构土仓内气体环境的检测方法及现场检测步骤,以便盾构法隧道施工现场气体检测方法更好地向施工企业推广,为安全施工提供参考。     

盾构管片接头简化数值模拟方法

由管片组装的盾构隧道衬砌环刚度分布不均,其薄弱环节为管片接头处。管片接头刚度的合理确定对于盾构隧道施工全过程模拟的合理性、地表沉降槽的确定以及土体损失的准确估算至关重要。根据管片接头受力特点及其构造,考虑对管片接头及其附近区域进行刚度修正,而管片其余区域保持原刚度不变,提出管片接头简化数值模拟方法——局部刚度修正法。基于圣维南原理和变刚度梁理论,推导了确定接头刚度的公式,并给出了相关参数的确定方法。结合室内盾构管片接头足尺试验成果,对不同荷载作用下管片接头的变形情况进行了数值模拟及对比分析。研究成果为盾构三维施工全过程的精细化数值模拟分析奠定了基础。     

盾构隧道近接下穿地下大型结构施工影响研究

建立了盾构掘进三维有限元模型,针对不同的盾构推进力和同步注浆未及时起到支撑作用的施工工况,采用数值模拟和室内相似模型试验方法进行了盾构隧道近接下穿地下大型结构施工的影响研究。研究结果表明,盾构掘进对地下结构周围土体扰动有限,不会产生隧道整体漂移。抗拔桩对地下结构的支撑作用明显,使得地下结构底板的拉应力和压应力交替出现,从而减小了应力量值。新建隧道和既有隧道衬砌结构受力是安全的,不需进行特殊设计。建议在近接地下结构之前10m处,调整盾构机姿态,放慢掘进速度,并将推进力控制在10000kN以内,以确保施工的安全进行。     

Evaluation of the load on shield tunnel lining in gravel

It is important to evaluate accurately the load acting on a shield tunnel lining to facilitate its economical and rational design. In Japan, the load calculated by Terzaghi's formula, or overburden load, is generally adopted for the design of tunnel segments. However, some previous field measurements have shown that the actual load acting on the shield tunnel lining could be much smaller than that adopted for the design in the case of good ground conditions. In this study, field measurements at two shield tunnel construction sites in gravel were carried out, and the load acting on the shield tunnel lining was evaluated by analyzing the field data to establish the rational design of the shield tunnel segments. The method of treating the dead load of segments in the design was also investigated.     

土压平衡盾构施工中盾构机的操作与管片选型

提出在盾构施工中盾构机操作者应具备的基本素质,分析目前盾构机操作者现状,总结在盾构隧道施工中盾构机的操作要点、管片选型的方法等,为相关人士提供参考。     

盾构隧道管片拼装技术

通过云南金河二级水电站导流隧道管片选型的实践，介绍了管片型号的选型原则，从管片的拼装点位、管片的选用等方面阐述了引水隧道施工中的管片拼装技术，使得隧道实际线路满足有关要求。     

简述盾构拼装管片过矿山法隧道施工

结合工程实际,介绍了盾构拼装管片过矿山法隧道施工,分析了施工过程中遇到的问题,并针对性地给出了具体的处理措施,提出了使盾构法与矿山法达成互补的建议,以充分利用两工法各自的优点,从而实现提高综合效益的目的.     

成都地铁浅埋暗挖隧道衬砌混凝土施工技术

介绍了成都地铁浅埋暗挖隧道衬砌混凝土施工技术,重点阐述了衬砌模板支架方案和混凝土输送施工方案,指出了该施工方案能经济快速地完成混凝土施工,取得了较好的经济效益和社会效益。     

地铁隧道承压水地层盾构机选型配套及施工实践

随着城市交通事业的蓬勃发展,越来越多的城市陆续修建城市轨道交通项目,其中盾构机施工技术已经是在地质条件复杂的城市轨道隧道施工中的主要技术之一。如济南地区具有承压水作用的全断面风化石灰岩、闪长岩地层,对盾构机的选型配套以及施工措施的实施等方面,存在诸多施工难题。文章以济南地铁R2号线烈士陵园站～开源路站盾构隧道工程为依托,通过查阅地勘资料,并参考国内其他城市类似地层施工经验,就承压水地层盾构机选型配套、刀具配置、掘进参数确定等方面进行研究,获得了适应该地层施工的施工盾构选型和配套模式以及施工工艺参数,对类似工程具有极强的借鉴意义。     

岩溶地层地铁盾构施工引起地下管线变形规律分析

岩溶地层修建地下工程往往会遇到岩溶溶洞等不良地质条件,严重影响了工程建设成效和安全.虽然采用注浆加固方法填充了部分岩溶溶洞起到了地层稳定性加固作用,但是地铁盾构施工依旧对于地层之中的既有结构物产生影响,严重者易造成结构沉降开裂.为此,本文依托深圳地铁16号线穿越岩溶地层段龙南-龙东村盾构区间工程,针对盾构侧穿地下管线引...     

盾构进站接收险情处理的探讨

地铁盾构进站接收施工是地铁盾构施工中的重点和难点,属于重大风险源,本文以福州地铁工程为实例,对地铁盾构进站接收的险情处理从地质情况、抢险措施、事故原因等进行介绍和分析,为今后地铁盾构施工遭遇类似的情况提供参考借鉴。     

Repair of displaced shield tunnel of the Taipei rapid transit system

A section of completed shield tunnel of the Panchiao Line of the Taipei Mass Rapid Transit (TRTS) was deformed and displaced due to an adjacent excavation. It was observed that the segments in the invert were separated from the concrete behind, and cracks were formed in the crown. In order to ensure that the shield tunnel section would meet the structural safety requirements set out by TRTS, the tunnel underwent repair work. This paper describes the damage, discusses the selection of repair methods, and outlines steel segment erection operations. It is the authors’ hope that the case presented would serve as a reference for other similar cases.     

Simplified nonlinear simulation of shield tunnel lining reinforced by epoxy bonded steel plates

A high-efficiency simplified modeling approach based on fiber-beam elements and discrete elements is proposed for investigating the nonlinear response of shield tunnel reinforced concrete linings. The proposed approach focus on following main features: modeling simplicity and computational efficiency, the considerations of critical material and geometric nonlinearity associated with the entire loading process, including the stage of reinforcing the deformed concrete lining by steel plates. Comparison between the analysis results of the proposed numerical model and the experimental results from the full-scale structural test are presented to validate the developed model. The results show that the proposed model can capture the essential characteristics of the nonlinear load–deformation response of segmental tunnel lining. The modeling approach presents a balance between simplicity and accuracy, and serves as a viable alternative to detailed finite elements analysis.