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Drive system design and error analysis of the 6 degrees of freedom segment erector of shield tunneling

Hu SHI, Guofang GONG, Huayong YANG

《机械工程前沿（英文）》 2011年 第6卷 第3期   页码 369-376 doi: 10.1007/s11465-011-0223-1

摘要：

Focusing on a segment erector of a shield-tunneling machine developed with 6 degrees of freedom (DOF) and controlled by electro-hydraulic proportional systems, the kinematics of the segment erection process is presented. The perturbation method in the error analysis is introduced to establish the position and attitude error model, considering a number of factors such as the hydraulic drive, control accuracy, and tolerance in manufacturing and assembly. Dynamic simulations are carried out to obtain the controlling precision of electrohydraulic drive systems. Formulas for calculating the position and attitude error of the grip hand of the segment erector are derived. The calculation results verify the practicality and effectiveness of the error analysis, providing a foundation for practical designing, manufacturing, and assembling of the segment of the erecting mechanism.

关键词： shield tunneling machine     segment erector     kinematics     position and attitude precision    

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A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 463-467 doi: 10.1007/s11465-011-0225-z

摘要：

The shield machine is a heavy construction machine for tunnel excavation, and the segment erector is an important subsystem of the shield machine. It is difficult to achieve precise control in the 6-DOF (degree of freedom) erector in the 2-DOF 5-bar radial mechanism. Hence, this paper proposes a redundantly actuated PRPRP radial mechanism for the segment erector. When the redundant actuator is unlocked, the radial mechanism is able to adjust its posture, which has two degrees of freedom. On the other hand, when the redundant actuator is locked or produces enough pre-tightening tensile force, the PRPRP mechanism can ensure the synchronization of the two driving hydraulic cylinders along the radial direction based on the mechanical structure, which has one degree of freedom. The redundant actuator also facilitates the equal application of two flexural torques at the hydraulic cylinders; thus, preventing the overload of a single cylinder.

关键词： redundant actuation     parallel mechanisms     five-bar mechanisms     segment erectors     shield machines    

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Bending failure performance of a shield tunnel segment based on full-scale test and numerical analysis

《结构与土木工程前沿（英文）》   页码 1033-1046 doi: 10.1007/s11709-023-0973-y

摘要： This study focuses on the bending failure performance of a shield tunnel segment. A full-scale test was conducted to investigate deformation and failure characteristics. During the loading, the bending failure process can be divided into four stages: the elastic stage, working stage with cracks, failure stage, and ultimate stage. The characteristic loads between contiguous stages are the cracking, failure, and ultimate loads. A numerical model corresponding to the test was established using the elastoplastic damage constitutive model of concrete. After a comparative analysis of the simulation and test results, parametric studies were performed to discuss the influence of the reinforcement ratio and proportion of tensile longitudinal reinforcement on the bearing capacity. The results indicated that the change in the reinforcement ratio and the proportion of tensile longitudinal reinforcement had little effect on the cracking load but significantly influenced the failure and ultimate loads of the segment. It is suggested that in the reinforcement design of the subway segment, the reinforcement ratio and the proportion of tensile longitudinal reinforcement can be chosen in the range of 0.7%–1.2% and 49%–55%, respectively, allowing the segment to effectively use the reinforcement and exert the design strength, thereby improving the bearing capacity of the segment.

关键词： shield tunnel     bearing capacity     failure mechanism     segment reinforcement    

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Manufacturing technique and performance of functionally graded concrete segment in shield tunnel

Baoguo MA, Dinghua ZOU, Li XU

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 101-104 doi: 10.1007/s11709-009-0011-8

摘要： The quality of segment is very important to the service life of shield tunnel. Concerning the complex engineering environment of the Wuhan Yangtze River Shield Tunnel, the principle of functionally graded materials was introduced to design and produce the functionally graded concrete segment (FGCS). Its key manufacturing technique was proposed and its performance was tested.

关键词： shield tunnel     functionally graded concrete segment (FGCS)     manufacturing technology     performance    

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The influence of hand hole on the ultimate strength and crack pattern of shield tunnel segment joints

Shaochun WANG, Xi JIANG, Yun BAI

《结构与土木工程前沿（英文）》 2019年 第13卷 第5期   页码 1200-1213 doi: 10.1007/s11709-019-0546-2

摘要： With the shield tunnel going deeper and deeper, the circumferential axial force becomes the governing factor rather than the bending moment. The hand hole acts as a weak point and initial damage in the segment joint especially when the circumferential axial force is extremely high. Despite the wide application of steel fiber or synthetic fiber in the tunneling, limited researches focus on the structural responses of segment joint with macro structural synthetic fiber (MSSF). In this paper, a 1:2 reduced-scale experiment was conducted to study the structural performance of the segment joint with different types of hand holes under ultra-high axial force. Special attention is paid to failure mode and structural performance (bearing capacity, deformation, cracking, and toughness). Moreover, segment joints with MSSF are also tested to evaluate the effects of MSSF on the failure mode and structural performance of the segment joints. The experiment results show that the hand hole becomes the weakest point of the segment joint under ultra-high axial force. A \ /-type crack pattern is always observed before the final failure of the segment joints. Different types and sizes of the hand hole have different degree of influences on the structural behavior of segment joints. The segment joint with MSSF shows higher ultimate bearing capacity and toughness compared to segment joint with common concrete. Besides, the MSSF improves the initial cracking load and anti-spallling resistance of the segment joint.

关键词： shield tunneling     structural synthetic fiber concrete     hand hole     segment joint     ultimate bearing capacity     crack pattern    

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Calculation of prestressed anchor segment by 3D infinite element

Yanfen WANG, Hongyang XIE, Yuanhan WANG

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 63-66 doi: 10.1007/s11709-009-0006-5

摘要： Based on 1D infinite element theory, the coordinate transformation and shape function of 3D point-radiation 4-node infinite elements were derived. They were coupled with 8-node finite elements to compute the compressive deformation of the prestressed anchor segment. The results indicate that when the prestressed force acts on the anchor segment, the stresses and displacements in the rock around the anchor segment are concentrated in the zone center with the anchor axis and are subjected to exponential decay. Therefore, the stresses and the displacement spindles are formed. The calculation results of the infinite element are close to the theoretical results.

关键词： infinite element     prestressed anchor     couple     finite element    

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软硬不均地层盾构姿态控制及管片防裂损技术

谭忠盛,洪开荣,万姜林,王梦恕

《中国工程科学》 2006年 第8卷 第12期   页码 92-96

摘要：

广州地铁二号线越—三盾构区间的地层软硬不均，加之曲线多、坡度变化大，盾构掘进技术难度大，掘进方向与盾构姿态的控制困难，防止管片开裂和局部破损以及错台具有一定的难度。为了有效地控制掘进方向和盾构姿态，研究了盾构掘进方向发生偏差的原因，并对越—三区间盾构掘进的偏差实测数据进行具体分析，得出了偏差的原因和规律；研究了盾构掘进姿态的控制方法。为了防止盾构管片的裂损，采用数值模拟方法研究管片裂损的规律及其主要因素，提出了有效控制管片裂损的主要方法。

关键词： 软硬不均地层     盾构     姿态控制     管片裂损     管片错台    

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Sensory innervation of the anterior eye segment in rats: a retrograde tracing study

Haixia LIU MD , Zhiwang LI MD , Min YANG MD , Xiang TIAN MS , Chaoying LI PhD , Lei PEI PhD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 352-356 doi: 10.1007/s11684-009-0065-y

摘要： This study aimed to investigate the sensory innervation of the anterior eye segment in rats by retrograde tracing with 1,1-dioleyl-3,3,3,3-tetrameth-ylindocarbocyanine, 4-chlorobenesulfonate (FAST Dil) injected into the anterior chamber. In our study, the sensory innervation of distinct elements of the anterior segment of the rat’s eye, i.e. the cornea, ciliary body, iris, and trabecular meshwork, were studied by retrograde tracing using FAST Dil as a tracer. FAST Dil was injected into the anterior chambers of the rat’s eyes. The animals were sacrificed at different time points, i.e., 2, 3, 4, and 5 days after the injection. FAST Dil localization in trigeminal ganglions was studied with a fluorescent microscope. Two days after FAST Dil injection into the anterior chambers, the cornea, the ciliary body, the iris, and the trabecular meshwork were heavily labeled. Neurons in the ipsilateral trigeminal ganglion were also consistently labeled. The number of labeled cells increased over time until 4 days after FAST Dil injection. FAST Dil-labeled neurons could be divided into two parts. Most of the Dil-labeled neurons were concentrated in a sharp, longitudinal, spindle-like stripe, located in the dorso-medial side of the trigeminal ganglion, approximately two thirds of the dorsal portion. The other part of Dil-labeled neurons scattered laterally to the stripe, but just in one third of the dorsal region. Thus, with our preliminary results, we conclude that the primary afferent sensory neurons innervating the rat’s anterior eye segments aggregate in the dorso-medial part of the ipsilateral trigeminal ganglion. It is feasible to identify them using retrograde tracing with FAST Dil anterior chamber injection.

关键词： trigeminal ganglion     retrograde tracing    

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大直径管片拼装及缺陷处理

程学武,许维青,杨志永

《中国工程科学》 2010年 第12卷 第12期   页码 89-93

摘要：

总结了北京地下直径线工程大直径盾构管片拼装技术，初步分析了大直径盾构钢筋混凝土管片施工过程中的表观破损原因，并对破损管片修补技术进行探讨，提出对拱腰以上、拱腰以下部位管片的不同修补方法，保证了大直径盾构管片的强度及外观质量。

关键词： 大直径盾构     管片     拼装     修补    

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系统工程方法在风云三号极轨气象卫星地面应用系统工程中的应用

董超华,杨忠东,施进明,张鹏

《中国工程科学》 2013年 第15卷 第10期   页码 24-32

摘要：

简要介绍了基于需求分析的风云三号（FY-3）卫星观测能力设计，并阐述了卫星地面应用系统如何利用系统工程方法进行地面系统顶层设计，统筹FY-3卫星和地面系统工程需求，合理布局地面接收站，科学划分地面系统各功能单元的任务，实现建成后的地面应用系统整体能力最大化。

关键词： FY-3卫星     观测能力     地面应用系统     系统工程     顶层设计    

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dislocation of the North-Tehran fault: The effects of geologic layering and slip distribution for the segment

Pooya ZAKIAN; Hossein ASADI HAYEH

《结构与土木工程前沿（英文）》 2022年 第16卷 第4期   页码 533-549 doi: 10.1007/s11709-022-0802-8

摘要： The present study uses the finite element method for simulating the crustal deformation due to the dislocation of a segment of the North-Tehran fault located in the Karaj metropolis region. In this regard, a geological map of Karaj that includes the fault segment is utilized in order to create the geometry of finite element model. First, finite element analysis of homogeneous counterpart of the fault’s domain with two different sections was performed, and the results were compared to those of Okada’s analytical solutions. The fault was modeled with the existing heterogeneity of the domain having been considered. The influences of both uniform and non-uniform slip distributions were investigated. Furthermore, three levels of simplification for geometric creation of geological layers’ boundaries were defined in order to evaluate the effects of the geometric complexity of the geological layering on the displacement responses obtained with the finite element simulations. In addition to the assessment of slip distribution, layering complexity and heterogeneity, the results demonstrate both the capability and usefulness of the proposed models in the dislocation analysis for the Karaj segment of North-Tehran fault.

关键词： finite element method     fault dislocation     slip distribution     the North-Tehran fault     heterogeneity     geological layering    

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the risk of heart failure and left ventricular systolic dysfunction in non-diabetic patients with ST-segment

Hui Wang, Yang Zhang, Zhujun Shen, Ligang Fang, Zhenyu Liu, Shuyang Zhang

《医学前沿（英文）》 2021年 第15卷 第1期   页码 70-78 doi: 10.1007/s11684-020-0749-x

摘要： Recent studies have shown that acute blood glucose elevation in patients with ST-segment elevation myocardial infarction (STEMI) suggests a poor prognosis. To investigate the effect of fasting blood glucose (FBG) on the risk of heart failure (HF) and left ventricular systolic dysfunction (LVSD) in non-diabetic patients undergoing primary percutaneous coronary intervention (PCI) for acute STEMI, we retrospectively recruited consecutive non-diabetic patients who underwent primary PCI for STEMI in our hospital from February 2003 to March 2015. The patients were divided into two groups according to the FBG level. A total of 623 patients were recruited with an age of 61.3±12.9 years, of whom 514 (82.5%) were male. The HF risk (odds ratio 3.401, 95% confidence interval (CI) 2.144–5.395, <0.001) was significantly increased in patients with elevated FBG than those with normal FBG. Elevated FBG was also independently related to LVSD (β 1.513, 95%CI 1.282–1.785, <0.001) in a multiple logistics regression analysis. In conclusion, elevated FBG was independently associated with 30-day HF and LVSD risk in non-diabetic patients undergoing primary PCI for STEMI.

关键词： myocardial infarction     percutaneous coronary intervention     diabetes mellitus     fasting glucose     heart failure    

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Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield tunnels

《结构与土木工程前沿（英文）》   页码 901-914 doi: 10.1007/s11709-023-0915-8

摘要： The integrity and bearing capacity of segment joints in shield tunnels are associated closely with the mechanical properties of the joints. This study focuses on the mechanical characteristics and mechanism of a bolted circumferential joint during the entire bearing process. Simplified analytical algorithms for four stress stages are established to describe the bearing behaviors of the joint under a compressive bending load. A height adjustment coefficient, α, for the outer concrete compression zone is introduced into a simplified analytical model. Factors affecting α are determined, and the degree of influence of these factors is investigated via orthogonal numerical simulations. The numerical results show that α can be specified as approximately 0.2 for most metro shield tunnels in China. Subsequently, a case study is performed to verify the rationality of the simplified theoretical analysis for the segment joint via numerical simulations and experiments. Using the proposed simplified analytical algorithms, a parametric investigation is conducted to discuss the factors affecting the ultimate compressive bending capacity of the joint. The method for optimizing the joint flexural stiffness is clarified. The results of this study can provide a theoretical basis for optimizing the design and prediciting the damage of bolted segment joints in shield tunnels.

关键词： shield tunnel     segment joint     joint structural model     failure mechanism    

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Deformation control criterion of shield tunnel under lateral relaxation of soft soil

《结构与土木工程前沿（英文）》 2023年 第17卷 第5期   页码 780-795 doi: 10.1007/s11709-023-0944-3

摘要： Metro shield tunnels under the lateral relaxation of soil (LRS) are susceptible to significant lateral deformations, which jeopardizes the structural safety and waterproofing. However, deformation control standards for such situations have not been clearly defined. Therefore, based on a specific case, a model test is conducted to realize the LRS of a shield tunnel in a sandy stratum to reveal its effect on segment liners. Subsequently, a deformation control criterion is established. The LRS is simulated by linearly reducing the loads applied to the lateral sides of the segment structure. During lateral unloading, the lateral earth pressure coefficient on the segment decreases almost exponentially, and the structural deformation is characterized by horizontal expansion at the arch haunches and vertical shrinkage at the arch vault and arch bottom. Based on the mechanical pattern of the segment structure and the acoustic emission, the deformation response of a segment can be classified into three stages: elastic and quasi-elastic, damage, and rapid deformation development. For a shield tunnel with a diameter of approximately 6 m and under the lateral relaxation of sandy soil, when the ellipticity of the segment is less than 2.71%, reinforcement measures are not required. However, the segment deformation must be controlled when the ellipticity is 2.71% to 3.12%; in this regard, an ellipticity of 3% can be used as a benchmark in similar engineering projects.

关键词： shield tunnel     lateral relaxation of soil     deformation control criterion of segment structure     model test    

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rectangle bin packing optimization approach to the signal scheduling problem in the FlexRay static segment

Rui ZHAO,Gui-he QIN,Jia-qiao LIU

《信息与电子工程前沿（英文）》 2016年 第17卷 第4期   页码 375-388 doi: 10.1631/FITEE.1500232

摘要： As FlexRay communication protocol is extensively used in distributed real-time applications on vehicles, signal scheduling in FlexRay network becomes a critical issue to ensure the safe and efficient operation of time-critical applications. In this study, we propose a rectangle bin packing optimization approach to schedule communication signals with timing constraints into the FlexRay static segment at minimum bandwidth cost. The proposed approach, which is based on integer linear programming (ILP), supports both the slot assignment mechanisms provided by the latest version of the FlexRay specification, namely, the single sender slot multiplexing, and multiple sender slot multiplexing mechanisms. Extensive experiments on a synthetic and an automotive X-by-wire system case study demonstrate that the proposed approach has a well optimized performance.

关键词： FlexRay     Real-time applications     Rectangle bin packing     Schedule optimization     Slot multiplexing    

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标题 作者 时间 类型 操作

Drive system design and error analysis of the 6 degrees of freedom segment erector of shield tunneling

Hu SHI, Guofang GONG, Huayong YANG

期刊论文

A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

期刊论文

Bending failure performance of a shield tunnel segment based on full-scale test and numerical analysis

期刊论文

Manufacturing technique and performance of functionally graded concrete segment in shield tunnel

Baoguo MA, Dinghua ZOU, Li XU

期刊论文

The influence of hand hole on the ultimate strength and crack pattern of shield tunnel segment joints

Shaochun WANG, Xi JIANG, Yun BAI

期刊论文

Calculation of prestressed anchor segment by 3D infinite element

Yanfen WANG, Hongyang XIE, Yuanhan WANG

期刊论文

软硬不均地层盾构姿态控制及管片防裂损技术

谭忠盛,洪开荣,万姜林,王梦恕

期刊论文

Sensory innervation of the anterior eye segment in rats: a retrograde tracing study

Haixia LIU MD , Zhiwang LI MD , Min YANG MD , Xiang TIAN MS , Chaoying LI PhD , Lei PEI PhD ,

期刊论文

大直径管片拼装及缺陷处理

程学武,许维青,杨志永

期刊论文

系统工程方法在风云三号极轨气象卫星地面应用系统工程中的应用

董超华,杨忠东,施进明,张鹏

期刊论文

dislocation of the North-Tehran fault: The effects of geologic layering and slip distribution for the segment

Pooya ZAKIAN; Hossein ASADI HAYEH

期刊论文

the risk of heart failure and left ventricular systolic dysfunction in non-diabetic patients with ST-segment

Hui Wang, Yang Zhang, Zhujun Shen, Ligang Fang, Zhenyu Liu, Shuyang Zhang

期刊论文

Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield tunnels

期刊论文

Deformation control criterion of shield tunnel under lateral relaxation of soft soil

期刊论文

rectangle bin packing optimization approach to the signal scheduling problem in the FlexRay static segment

Rui ZHAO,Gui-he QIN,Jia-qiao LIU

期刊论文