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Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

《结构与土木工程前沿(英文)》 2023年 第17卷 第7期   页码 994-1010 doi: 10.1007/s11709-023-0942-5

摘要: The moving trajectory of the pipe-jacking machine (PJM), which primarily determines the end quality of jacked tunnels, must be controlled strictly during the entire jacking process. Developing prediction models to support drivers in performing rectifications in advance can effectively avoid considerable trajectory deviations from the designed jacking axis. Hence, a gated recurrent unit (GRU)-based deep learning framework is proposed herein to dynamically predict the moving trajectory of the PJM. In this framework, operational data are first extracted from a data acquisition system; subsequently, they are preprocessed and used to establish GRU-based multivariate multistep-ahead direct prediction models. To verify the performance of the proposed framework, a case study of a large pipe-jacking project in Shanghai and comparisons with other conventional models (i.e., long short-term memory (LSTM) network and recurrent neural network (RNN)) are conducted. In addition, the effects of the activation function and input time-step length on the prediction performance of the proposed framework are investigated and discussed. The results show that the proposed framework can dynamically and precisely predict the PJM moving trajectory during the pipe-jacking process, with a minimum mean absolute error and root mean squared error (RMSE) of 0.1904 and 0.5011 mm, respectively. The RMSE of the GRU-based models is lower than those of the LSTM- and RNN-based models by 21.46% and 46.40% at the maximum, respectively. The proposed framework is expected to provide an effective decision support for moving trajectory control and serve as a foundation for the application of deep learning in the automatic control of pipe jacking.

关键词: dynamic prediction     moving trajectory     pipe jacking     GRU     deep learning    

Investigation of the first quasi-rectangular metro tunnel constructed by the 0- method

《结构与土木工程前沿(英文)》 2023年 第17卷 第11期   页码 1707-1722 doi: 10.1007/s11709-023-0991-9

摘要: Quasi-rectangular shield tunneling is a cutting-edge trenchless method for constructing metro tunnels with double tubes, owing to its advantages in saving underground space and reducing ground disturbance. However, the conventional quasi-rectangular shield tunneling method is not applicable when constructing a tunnel without a center pillar, such as a scissor crossover section of a metro line. Therefore, the 0-θ tunneling method, which combines the quasi-rectangular shield and pipe jacking methods, was investigated in this study to solve the aforementioned construction challenges. This study presents a case study of the Sijiqing Station of the Hangzhou Metro Line 9 in China, in which the 0-θ method was first proposed and applied. Key techniques such as switching between two types of tunneling modes and the tunneling process control in complex construction environments were investigated. The results demonstrated that the 0-θ method can address the technical challenges presented by the post-transition line with a high curvature and a scissors crossover line. In addition, the adoption of the 0-θ method ensured that the transformation between shield tunneling and pipe jacking was safe and efficient. The ground settlement monitoring results demonstrated that the disturbance to the surrounding environment can be limited to a safe level. This case study contributes to the construction technology for a metro tunnel containing both post-transition lines with a small turning radius and a scissors crossover line. A practical construction experience and theoretical guidance were provided in this study, which are of significance for both the industry and academia.

关键词: quasi-rectangular tunnel     0-θ method     pipe jacking     shield tunneling     underground space    

异形掘进机设计制造关键技术研究及工程应用

李建斌

《工程(英文)》 2017年 第3卷 第6期   页码 905-914 doi: 10.1016/j.eng.2017.12.002

摘要:
随着地下空间开发进程的加快,越来越多的大型掘进机(TBM)应用于地下工程开挖。目前,常规TBM 已无法完全满足地下工程对断面形式和空间利用率的追求,异形TBM 成为理想断面开挖设备成为市场新的增长点。本文首先介绍了异形TBM 的技术特点及发展现状,然后结合典型工程与工法创新,针对矩形顶管和马蹄形TBM 开展了盾体结构设计优化、多刀盘联合开挖、异形管片拼装、黄土地层渣土改良等多项关键技术研究,为异形断面TBM 的设计、制造和施工提供了一套可行的解决方案。相关工程实践表明,采用针对性设计、制造的异形TBM,在施工进度、地表沉降控制和空间利用等方面具有巨大优势。

关键词: 异形TBM     矩形顶管机     马蹄形TBM     地下空间开发    

Major applications of heat pipe and its advances coupled with sorption system: a review

Yang YU, Guoliang AN, Liwei WANG

《能源前沿(英文)》 2019年 第13卷 第1期   页码 172-184 doi: 10.1007/s11708-019-0610-6

摘要: Heat pipe utilizes continuous phase change process within a small temperature drop to achieve high thermal conductivity. For decades, heat pipes coupled with novel emerging technologies and methods (using nanofluids and self-rewetting fluids) have been highly appreciated, along with which a number of advances have taken place. In addition to some typical applications of thermal control and heat recovery, the heat pipe technology combined with the sorption technology could efficiently improve the heat and mass transfer performance of sorption systems for heating, cooling and cogeneration. However, almost all existing studies on this combination or integration have not concentrated on the principle of the sorption technology with acting as the heat pipe technology for continuous heat transfer. This paper presents an overview of the emerging working fluids, the major applications of heat pipe, and the advances in heat pipe type sorption system. Besides, the ongoing and perspectives of the solid sorption heat pipe are presented, expecting to serve as useful guides for further investigations and new research potentials.

关键词: heat pipe     sorption system     heat transfer     solid sorption heat pipe    

Design and analyses of open-ended pipe piles in cohesionless soils

Yuan GUO,Xiong (Bill) YU

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 22-29 doi: 10.1007/s11709-016-0314-5

摘要: Large open-ended pipe pile has been found to be advantageous for use in transportation projects. The current design method, however, is not adequately developed. To close this practice gap, this paper first summarized different design methods for open-ended pipe piles in sandy soils. A major factor for all the design codes is to properly account for the formation and effects of soil plug. The comparison indicates that there is a large variation in the base capacity evaluation among different methods due to the complex behaviors of soil plug. To close the knowledge gap, discrete element method (DEM) was used to simulate the soil plugging process and provide insight on the plugging mechanism. The simulation results show that the arching effect significantly increases the internal unit shear resistance along pipe piles. The porosity distribution and particle contact force distribution from DEM model indicate a large stress concentration occurs at the bottom of the soil plug. Besides, nearly 90% of the plug resistance is provided by the bottom half portion of the soil column. The soil-pile friction coefficient has a significant effect on the magnitude of plug resistance, with the major transition occurred for friction coefficient between 0.3 and 0.4.

关键词: open-ended pipe pile     soil plug     DEM     base capacity    

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 798-813 doi: 10.1007/s11465-021-0645-3

摘要: External pipe routing for aero-engine in limited three-dimensional space is a typical nondeterministic polynomial hard problem, where the parallel layout of pipes plays an important role in improving the utilization of layout space, facilitating pipe assembly, and maintenance. This paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel layout. The compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be routed. Based on these rough paths, the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree, respectively. Subsequently, a coevolutionary improved differential evolution algorithm, which adopts the coevolutionary strategy, is used to solve multiple pipe layout optimization problem. By using this algorithm, pipes in the same group share the layout space information with one another, and the optimal layout solution of pipes in this group can be obtained in the same evolutionary progress. Furthermore, to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly, an accurate parallelization processing method based on the simulated annealing algorithm is proposed. Finally, the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词: multiple pipe routing     optimization algorithm     aero-engine     pipe grouping     parallel layout    

Construction of shallow buried large-span metro stations using the small pipe roof-beam method

《结构与土木工程前沿(英文)》 2024年 第18卷 第1期   页码 122-136 doi: 10.1007/s11709-024-1008-z

摘要: In relation to the Shifu Road Station project on Line 4 of the Shenyang Metro in China, a small-pipe roof-beam method for constructing subway stations is presented. First, a numerical simulation was performed to optimize the supporting parameters of the proposed method and determine the design scheme. Subsequently, the deformation of the pipe roof and surface settlement during the construction process were investigated. Finally, the surface settlement attributed to the excavation was studied through field monitoring, and the proposed method was compared with other methods. The results show that an increase in the pipe-roof spacing has little effect on the surface settlement and pipe-roof deformation. The bearing capacity of the pipe roof can be efficiently utilized once the flexural stiffness reaches 2EI, and the flexural stiffness is not the dominant factor controlling the deformation. The essential stages in controlling surface settlement are the excavations of the transverse pilot tunnels and the soil between them. The final settlement value of the ground was 24.1 mm, resulting in a reduction in the construction period by at least five months while satisfying the control requirements.

关键词: subway station     pipe-roof method     surface settlement     simulation     on-site monitoring    

A 3D sliced-soil–beam model for settlement prediction of tunnelling using the pipe roofing method in

《结构与土木工程前沿(英文)》 2023年 第17卷 第12期   页码 1934-1948 doi: 10.1007/s11709-023-0038-2

摘要: The pipe roofing method is widely used in tunnel construction because it can realize a flexible section shape and a large section area of the tunnel, especially under good ground conditions. However, the pipe roofing method has rarely been applied in soft ground, where the prediction and control of the ground settlement play important roles. This study proposes a sliced-soil–beam (SSB) model to predict the settlement of ground due to tunnelling using the pipe roofing method in soft ground. The model comprises a sliced-soil module based on the virtual work principle and a beam module based on structural mechanics. As part of this work, the Peck formula was modified for a square-section tunnel and adopted to construct a deformation mechanism of soft ground. The pipe roofing system was simplified to a three-dimensional Winkler beam to consider the interaction between the soil and pipe roofing. The model was verified in a case study conducted in Shanghai, China, in which it provided the efficient and accurate prediction of settlement. Finally, the parameters affecting the ground settlement were analyzed. It was clarified that the stiffness of the excavated soil and the steel support are the key factors in reducing ground settlement.

关键词: pipe roofing method     soft ground     numerical simulation     settlement prediction     simplified calculation     parametric analysis    

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 241-248 doi: 10.1007/s11465-011-0219-x

摘要:

This paper presents a new calculation method that can calculate the load distribution on pipe threaded connections under tension load. On the basis of elastic mechanics, the new method was developed by analyzing each thread tooth, and a new deformation and covariant equation by making a mechanics analysis on each thread tooth was obtained. Compared with the traditional method proposed by the previous references, the new deformation and covariant equation could be used to describe the relation between the previous and the next thread tooth. By applying the new method on the sample of P-110S pipe threaded connection, the obtained results show that the load on thread tooth mainly concentrates on the four or five threads engaged and the middle teeth were not utilized well to bear the loads. The model offers a new way to calculate the loads carried on the thread teeth under tension load.

关键词: load distribution     calculation method     pipe threaded connections     tension load    

NC flame pipe cutting machine tool based on open architecture CNC system

Xiaogen NIE, Yanbing LIU

《机械工程前沿(英文)》 2009年 第4卷 第2期   页码 147-152 doi: 10.1007/s11465-009-0025-x

摘要: Based on the analysis of the principle and flame movement of a pipe cutting machine tool, a retrofit NC flame pipe cutting machine tool (NFPCM) that can meet the demands of cutting various pipes is proposed. The paper deals with the design and implementation of an open architecture CNC system for the NFPCM, many of whose aspects are similar to milling machines; however, different from their machining processes and control strategies. The paper emphasizes on the NC system structure and the method for directly creating the NC file according to the cutting type and parameters. Further, the paper develops the program and sets up the open and module NC system.

关键词: flame pipe cutting     flame incision tracks     CNC     open architecture CNC system    

Assessment of glass fiber-reinforced polyester pipe powder in soil improvement

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 742-753 doi: 10.1007/s11709-021-0732-x

摘要: This study investigates the use of glass fiber-reinforced polyester (GRP) pipe powder (PP) for improving the bearing capacity of sandy soils. After a series of direct share tests, the optimum PP addition for improving the bearing capacity of soils was found to be 12%. Then, using the optimum PP addition, the bearing capacity of the soil was estimated through a series of loading tests on a shallow foundation model placed in a test box. The bearing capacity of sandy soil was improved by up to 30.7%. The ratio of the depth of the PP-reinforced soil to the diameter of the foundation model (H/D) of 1.25 could sufficiently strengthen sandy soil when the optimum PP ratio was used. Microstructural analyses showed that the increase in the bearing capacity can be attributed to the chopped fibers in the PP and their multiaxial distribution in the soil. Besides improving the engineering properties of soils, using PP as an additive in soils would reduce the accumulation of the industrial waste, thus providing a twofold benefit.

关键词: shallow foundation     sandy soil     bearing capacity     soil improvement     pipe powder    

A review of nondestructive examination technology for polyethylene pipe in nuclear power plant

Jinyang ZHENG, Yue ZHANG, Dongsheng HOU, Yinkang QIN, Weican GUO, Chuck ZHANG, Jianfeng SHI

《机械工程前沿(英文)》 2018年 第13卷 第4期   页码 535-545 doi: 10.1007/s11465-018-0515-9

摘要:

Polyethylene (PE) pipe, particularly high-density polyethylene (HDPE) pipe, has been successfully utilized to transport cooling water for both non-safety- and safety-related applications in nuclear power plant (NPP). Though ASME Code Case N755, which is the first code case related to NPP HDPE pipe, requires a thorough nondestructive examination (NDE) of HDPE joints. However, no executable regulations presently exist because of the lack of a feasible NDE technique for HDPE pipe in NPP. This work presents a review of current developments in NDE technology for both HDPE pipe in NPP with a diameter of less than 400 mm and that of a larger size. For the former category, phased array ultrasonic technique is proven effective for inspecting typical defects in HDPE pipe, and is thus used in Chinese national standards GB/T 29460 and GB/T 29461. A defect-recognition technique is developed based on pattern recognition, and a safety assessment principle is summa-rized from the database of destructive testing. On the other hand, recent research and practical studies reveal that in current ultrasonic-inspection technology, the absence of effective ultrasonic inspection for large size was lack of consideration of the viscoelasticity effect of PE on acoustic wave propagation in current ultrasonic inspection techno-logy. Furthermore, main technical problems were analyzed in the paper to achieve an effective ultrasonic test method in accordance to the safety and efficiency requirements of related regulations and standards. Finally, the development trend and challenges of NDE test technology for HDPE in NPP are discussed.

关键词: polyethylene pipe     nuclear power plant     ultrasonic inspection     nondestructive testing     safety assessment    

Branch-pipe-routing approach for ships using improved genetic algorithm

Haiteng SUI,Wentie NIU

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 316-323 doi: 10.1007/s11465-016-0384-z

摘要:

Branch-pipe routing plays fundamental and critical roles in ship-pipe design. The branch-pipe-routing problem is a complex combinatorial optimization problem and is thus difficult to solve when depending only on human experts. A modified genetic-algorithm-based approach is proposed in this paper to solve this problem. The simplified layout space is first divided into three-dimensional (3D) grids to build its mathematical model. Branch pipes in layout space are regarded as a combination of several two-point pipes, and the pipe route between two connection points is generated using an improved maze algorithm. The coding of branch pipes is then defined, and the genetic operators are devised, especially the complete crossover strategy that greatly accelerates the convergence speed. Finally, simulation tests demonstrate the performance of proposed method.

关键词: branch pipe     ship industry     piping system     optimization algorithm    

End-of-pipe or process-integrated: evidence from LMDI decomposition of China’s SO

Pingdan ZHANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 867-874 doi: 10.1007/s11783-013-0541-0

摘要: In this study, reduction in sulfur dioxide (SO ) emission is decomposed into three parts: source prevention, process control and end-of-pipe treatment, using the Logarithmic Mean Divisia Index method (LMDI). Source prevention and process control are defined as process-integrated treatment. It is found that from 2001 to 2010 the reduction of SO emission density in China was mainly contributed by end-of-pipe treatment. From the 10th Five Year Plan (FYP) period (2001–2005) to the 11th FYP period (2006–2010), the Chinese government has attempted to enhance process-integrated treatment. However, given its initial effort, the effect is limited compared with that of the end-of-pipe treatment. The effectiveness of environmental regulation and technology in the reduction of SO density in 30 provinces (municipality/autonomous regions) from 2001 to 2010 is also investigated. This implies that environmental regulation and technology promote process control and end-of-pipe treatment significantly, but does not influence source prevention. Furthermore, environmental technology will only take effect under the circumstances of stringent environmental regulation. Therefore, to fulfill the whole process treatment, environmental regulation should be strengthened and environmental technology upgraded at the same time.

关键词: end-of-pipe     process-integrated     Logarithmic Mean Divisia Index method (LMDI)     environmental regulation     environmental technology    

标题 作者 时间 类型 操作

Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

期刊论文

World’s first implementation of close-fit pipe jacking of twin tunnels for construction of subway station

期刊论文

Investigation of the first quasi-rectangular metro tunnel constructed by the 0- method

期刊论文

异形掘进机设计制造关键技术研究及工程应用

李建斌

期刊论文

Major applications of heat pipe and its advances coupled with sorption system: a review

Yang YU, Guoliang AN, Liwei WANG

期刊论文

Design and analyses of open-ended pipe piles in cohesionless soils

Yuan GUO,Xiong (Bill) YU

期刊论文

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

期刊论文

Construction of shallow buried large-span metro stations using the small pipe roof-beam method

期刊论文

A 3D sliced-soil–beam model for settlement prediction of tunnelling using the pipe roofing method in

期刊论文

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

期刊论文

NC flame pipe cutting machine tool based on open architecture CNC system

Xiaogen NIE, Yanbing LIU

期刊论文

Assessment of glass fiber-reinforced polyester pipe powder in soil improvement

期刊论文

A review of nondestructive examination technology for polyethylene pipe in nuclear power plant

Jinyang ZHENG, Yue ZHANG, Dongsheng HOU, Yinkang QIN, Weican GUO, Chuck ZHANG, Jianfeng SHI

期刊论文

Branch-pipe-routing approach for ships using improved genetic algorithm

Haiteng SUI,Wentie NIU

期刊论文

End-of-pipe or process-integrated: evidence from LMDI decomposition of China’s SO

Pingdan ZHANG

期刊论文