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Enhanced wear prediction of tunnel boring machine disc cutters for accurate remaining useful life estimation using a hybrid model

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 642-662页

作者： Xinghai ZHOU Yakun ZHANG Guofang GONG Huayong YANG Qiaosong CHEN Yuxi CHEN Zhixue SU The State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China Guangzhou Rail Transit construction Engineering co.sulting co. Ltd.Guangzhou 510000China china railway Engineering Equipment group co. Ltd.Zhengzhou 450016China

In tunnel construction with tunnel boring machines(TBMs),accurate prediction of the remaining useful life(RUL)of disc cutters is critical for timely maintenance and replacement to avoid delays and co.t *** paper introduces a novel hybrid model,integrating fundamental and data-driven approaches,to enhance wear prediction of TBM disc cutters and enable accurate RUL *** fundamental model is improved by inco.porating co.posite wear mechanisms and load estimation techniques,showcasing superior prediction accuracy co.pared to single-mechanism ***,the hybrid model innovatively inco.porates a data-driven supplementary residual term into the improved fundamental model,leading to a high-performance wear prediction *** actual field data from a highway tunnel project in Shenzhen,the performance of the hybrid model is rigorously tested and co.pared with pure fundamental and data-driven *** hybrid model outperforms the other models,achieving the highest accuracy in predicting TBM disc cutter wear(mean absolute error(MAE)=0.53,root mean square error(RMSE)=0.64).Furthermore,this study thoroughly analyzes the hybrid model’s generalization capability,revealing significant impacts of geological co.ditions on prediction *** model’s generalization capability is also improved by expanding and updating the data *** RUL estimation results provided by the hybrid model are straightforward and effective,making it a valuable tool by which construction staff can monitor TBM disc cutters.

关键词： tunnel boring machine disc cutter wear prediction remaining useful life field data hybrid model

Hydration Behavior and Cementitious Properties of Calcium Carbonate-aluminate Minerals co.posite

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 126-133页

作者：王冲周帅 ZOU Luyao LIU Jiawen ZHENG Yalin co.lege of Materials Science and Engineering Chongqing UniversityChongqing 400045China china West construction group co. Ltd.Chengdu 610015China

The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementitious material. The co.posite system of calcium carbonate and aluminate minerals is studied by measuring the co.ponent of hydration products, the hydration heat, setting time and co.pressive *** results prove that the co.posite system has certain cementitious properties and is feasible to prepare new low-carbon cement.

关键词： limestone hydrated calcium carboaluminate cementitious properties mechanical properties

An alternative approach to improve the co.patibility of PCE in cement paste blend with co.l gangue powder

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Waste Disposal and Sustainable Energy 2024年第1期6卷 139-150页

作者： Zonglin Xie Yuxuan Li Dahui Sun Yi Tian Jinyuan Hu Qiang Yuan Zheng Chen School of Civil Engineering Central South UniversityChangshaChina china railway NO.9 group co. LTDShenyangChina National Engineering Research Center for High-Speed railway construction Technology ChangshaChina Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanningChina

co.l gangue(CG)is an environmental waste that faces an urgent demand for disposal in *** utilization of CG in construction materials has broad application prospects and gained increasing ***,the poor co.patibility of polycarboxylate superplasticizer(PCE)with CG powder hinders its efficiency in a wide range of ***,this paper attempts to improve the co.patibility of PCE with CG powder in cement paste based on the regulation of aggregation and the adsorption behavior of *** light scattering(DLS)and fluorescence spectrosco.y tests were carried out to understand the improved *** results indicated that the addition of CG powder increases the ionic strengths of the cement liquid phase,which makes PCE tend to aggregate at a lower co.centration co.pared with no CG powder ***(CH_(3)co.)_(2)Cu is beneficial for enhancing the workability of cement paste by reducing PCE aggregation while maintaining the co.pressive strength of cement ***,(CH_(3)co.)_(2)Cu extra addition can be regarded as an effective and sustainable way to improve the workability of cement paste with CG powder.

关键词： co.l gangue powder Polycarboxylate superplasticizer co.patibility Aggregation

Technical innovation in the “Beishan No. 1” hard rock tunnel boring machine for high-gradient spiral tunnels

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Frontiers of Engineering Management 2024年第1期11卷 175-179页

作者： Ju WANG Mengxue QI Bin LONG Hongsu MA Beijing Research Institute of Uranium Geology Beijing 100029China china railway 18th Bureau group Tunnel Engineering co. Ltd.Chongqing 400700China china railway construction Heavy Industry co. Ltd.Changsha 410100China

1 Project overview The“Beishan No.1”,the world’s first-ever hard rock Tunnel Boring Machine(TBM)tailored for high-gradient spiral tunnels,co.stitutes a pivotal element within the Beishan Underground Research Laboratory(URL)initiative in *** URL,the first URL for geological disposal of high level radioactive waste(HLW)in china,is a national key construction project listed in the“13th Five-Year Plan”.In 2019,subsequent to receiving approval from the china Atomic Energy Authority,the Beijing Research Institute of Uranium Geology(BRIUG),serving as the project’s owner,initiated its *** underground facility,categorized as a“third generation”URL for HLW disposal,i.e.,area-specific URL,was located in Beishan,Jiuquan City,Gansu Province,china,following more than three decades of rigorous research on site selection.

关键词： tunnel boring machine extremely hard rock co.tinuous small-radius curves high gradient equipment technology innovation

Development and engineering application of integrated safety monitoring systems for china’s high-speed trains

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Transportation Safety and Environment 2024年第2期6卷 36-44页

作者： Yan Zhu Tiantian Wang Ruiyuan Shen Jingsong Xie Jingsong Yang Guoqin Zhang Hongqi Tian Xifeng Liang School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina CRRC Changchun railway Vehicles co. LtdChangchun 130062JilinChina china State railway group co. Ltd.Beijing 100084China

With the improvement of the running speed of china’s high-speed trains,the demands for running status monitoring and security assurance of High-speed Electric Multiple Units(EMU)have increased ***,the current safety monitoring systems are independent,which is not co.ducive to the co.prehensive monitoring and information sharing of the whole *** temperature monitoring of running gear is insensitive to early *** to develop a train operation safety monitoring system with strong engineering implementation and high integration is a key problem to be *** the monitoring of running stationarity,frame stability and running gear health of china’s high-speed trains,an integrated safety monitoring system framework is designed,and the logic and algorithm for the diagnosis of stationarity,stability and health states of rotating parts are *** software which fused the temperature,high and low frequency vibration data is developed,and the design and installation of the vibration temperature co.posite sensors are *** research results have realized the integration and co.prehensive processing of multiple monitoring systems,co.pleted the improvement from single co.ponent and vehicle-level safety monitoring to multi-system,train-level and interactive *** the process of real vehicle application,the developed monitoring system acquires the vehicle operation status data accurately and in real *** co.structed diagnosis algorithm and logic evaluates the vehicle operation status accurately and in a timely manner,and avoids the progression from fault to *** research results show that the integrated safety monitoring system can provide technical support for train operation safety.

关键词： electric multiple units(EMU) integrated safety monitoring system stationarity stability fault diagnosis

Analysis of Calcined Red Mud Properties and Related Mortar Performances

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Fluid Dynamics & Materials Processing 2024年第5期20卷 901-913页

作者： Zhengfan Lyu Yulin Li Mengmeng Fan Yan Huang Chenguang Li Technical Center Office Guangxi Jiaojian Engineering Inspection Consulting Co.Ltd.Nanning530001China Technical Center Office Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China Nanning Road construction Technology and Road construction Materials Engineering Technology Research Centre Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China

Red mud(RM)is a low-activity industrial solid waste,and its utilization as a resource is currently a hot *** this study,the micro characteristics of red mud at different calcination temperatures were analyzed using X-ray diffraction and scanning electron *** performance of calcined red mud was determined through mortar strength *** indicate that high-temperature calcination can change the mineral co.position and microstructure of red mud,and increase the surface roughness and specific surface *** the optimal temperature of 700°C,the addition of calcined red mud still leads to a decrease in mortar strength,but its activity index and flexural co.fficient increase by 16.2%and 11.9%with respect to uncalcined red mud,reaching values of 0.826 and 0.974,*** with the co.trol group,the synergistic activation of calcined red mud with slag can increase the co.pressive and flexural strength of the mortar by 12.9%and 1.5%,reaching 8.7 and 62.4 MPa,***,the activity index and flexural co.fficient of the calcined RM and GGBS(Ground Granulated Blast furnace Slag)mixtures also increase to 1.015 and 1.130,respectively.

关键词： Red mud slag thermal activation synergistic activation mortar test microsco.ic properties

Research on the design method for uniform wear of shield cutters in sand-pebble strata

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Deep Underground Science and Engineering 2024年第2期3卷 216-230页

作者： Jinxun Zhang Bo Li Guihe Wang Yusheng Jiang Hua Jiang Minglun Yin Zhengyang Sun Beijing Urban construction group co. Ltd.BeijingChina china University of Geosciences BeijingChina china University of Mining and Technology BeijingChina

During shield tunneling in highly abrasive formations such as sand–pebble strata,nonuniform wear of shield cutters is inevitable due to the different cutting *** downtimes and cutter replacements have beco.e major obstacles to long-distance shield driving in sand–pebble *** on the cutter wear characteristics in sand–pebble strata in Beijing,a design methodology for the cutterhead and cutters was established in this study to achieve uniform wear of all cutters by the principle of frictional *** applicability of the design method was verified through three-dimensional simulations using the engineering discrete element *** results show that uniform wear of all cutters on the cutterhead co.ld be achieved by installing different numbers of cutters on each trajectory radius and designing a curved spoke with a certain arch height acco.ding to the shield *** the uniform wear scheme,the cutter wear co.fficient is greatly reduced,and the largest shield driving distance is increased by approximately 47%over the engineering *** research results indicate that the problem of nonuniform cutter wear in shield excavation co.ld be overco.e,thereby providing guiding significance for theoretical innovation and construction of long-distance shield excavation in highly abrasive strata.

关键词： cutter wear EDEM model long-distance shield driving sand-pebble stratum shield tunnel uniform wear design method

Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect

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Journal of Mountain Science 2024年第3期21卷 1058-1074页

作者： CHENG Yun SONG Zhanping XU Zhiwei YANG Tengtian TIAN Xiaoxu School of Civil Engineering Yancheng Institute of TechnologyYancheng 224051China School of Civil Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering Xi'an 710055China china railway construction Bridge Engineering Bureau group co. Ltd.Tianjin 300300China

The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial co.pression tests, co.pled with aco.stic emission(AE) and infrared radiation temperature(IRT) were co.ducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative co.relation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), co.posite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and co.posite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the co.petitive relationship between co.paction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关键词： Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism Dissimilation

Regression Method for Rail Fastener Tightness Based on Center-Line Projection

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 356-371页

作者： Yuanhang Wang Duxin Liu Sheng Guo Yifan Wu Jing Liu Wei Li Hongjie Wang Robotics Research Center School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China china construction Industrial&Energy Engineering group co. Ltd.Nanjing 210023China

In the railway system,fasteners have the functions of damping,maintaining the track distance,and adjusting the track ***,routine maintenance and inspection of fasteners are important to ensure the safe operation of track ***,assessment methods for fastener tightness include manual observation,aco.stic wave detection,and image *** are limitations such as low accuracy and efficiency,easy interference and misjudgment,and a lack of accurate,stable,and fast detection *** at the small deformation characteristics and large elastic change of fasteners from full loosening to full tightening,this study proposes high-precision surface-structured light technology for fastener detection and fastener deformation feature extraction based on the center-line projection distance and a fastener tightness regression method based on neural ***,the method uses a 3D camera to obtain a fastener point cloud and then segments the elastic rod area based on the iterative closest point algorithm *** co.ponent analysis is used to calculate the normal vector of the segmented elastic rod surface and extract the point on the centerline of the elastic *** point is projected onto the upper surface of the bolt to calculate the projection ***,the mapping relationship between the projection distance sequence and fastener tightness is established,and the influence of each parameter on the fastener tightness prediction is ***,by setting up a fastener detection scene in the track experimental base,co.lecting data,and co.pleting the algorithm verification,the results showed that the deviation between the fastener tightness regression value obtained after the algorithm processing and the actual measured value RMSE was 0.2196 mm,which significantly improved the effect co.pared with other tightness detection methods,and realized an effective fastener tightness regression.

关键词： railway system Fasteners Tightness inspection Neural network regression 3D point cloud processing