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Research on an innovative structure of an open-ribbed steel–ultra-high performance concrete composite bridg

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Frontiers of Structural and Civil engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO Xuan SUN Deqiang ZOU Junhui CAO Chuanqi YANG School of Civil engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China China construction Fifth engineering division Co. Ltd.Changsha 410004China

To completely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSDs),the authors proposed a steel–ultra-high performance concrete(UHPC)lightweight composite deck(LWCD)with closed ribs in *** on the successful application of that LWCD,an adaptation incorporating an innovative composite deck structure,i.e.,the hot-rolled section steel–UHPC composite deck with open ribs(SSD)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the cost of *** on a long-span cable-stayed bridge,a design scheme is proposed and is compared with the conventional OSD ***,a finite element(FE)calculation is conducted to reflect both the global and local behavior of the SSD scheme,and it is found that the peaked stresses in the SSD components are less than the corresponding allowable values.A static test is performed for an SSD strip specimen to understand the anti-cracking behavior of the UHPC layer under negative bending *** static test results indicate that the UHPC layer exhibited a satisfactory tensile toughness,the UHPC tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSD are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSD are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the corresponding constant amplitude fatigue *** a fatigue test is carried out for another SSD strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSD could meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance concrete composite deck open rib strip model test static and fatigue performance orthotropic steel deck

Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第6期25卷 483-501页

作者： Yuansheng YU Lingling LI Xiangmiao KONG Chengyuan LI Zhen GUO Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Hainan Institute Zhejiang UniversitySanya572000China Ninghai Highway and Transportation management Center Ningbo315600China Ninghai Traffic engineering construction management Institute Ningbo315600China

The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 24 h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability.

关键词： construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)

Wellbore-heat-transfer-model-based optimization and control for cooling downhole drilling fluid

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Petroleum Science 2024年第3期21卷 1955-1968页

作者： Chao Wang He Liu Guo-Wei Yu Chen Yu Xian-Ming Liu Peng Huang Yangtze University Jingzhou434023HubeiChina State Key Laboratory of Petroleum Resources and engineering China University of Petroleum(Beijing)Beijing2249China CNPC Bohai Drilling engineering Co. LtdTianjin300280China Exploration Development and construction engineering division of PetroChina Jidong Oilfield Company Tangshan63200HebeiChin Henan University of Urban construction Pingdingshan467036HenanChina

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology,we first established a temperature and pressure coupled downhole heat transfer model,which can be used in both water-based and oil-based drilling ***,fourteen factors,which could affect wellbore temperature,were *** on the standard deviation of the downhole temperature corresponding to each influencing factor,the influence of each factor was *** influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity,drilling fluid heat capacity,drilling fluid density,drill strings rotation speed,pump rate,viscosity,ROP,and injection *** nondominated sorting genetic algorithm was used to optimize these six parameters,but the optimization process took 182 *** these eight parameters'influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 ***,the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady *** this law and PID,the downhole temperature can be controlled,which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling Cooling Influencing factors Analysis Optimization Control

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How Does Participation in Agricultural Cooperatives Affect the Performance of Family Farms?——Empirical Evidence from 553 Planting Family Farms in Xinjiang Corps

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Journal of Systems Science and Information 2024年

作者： Zhiping HUANG Na LI Xishan Farmland The 12th Division of Xinjiang Production and Construction Corps School of Economics and management University of Chinese Academy of Sciences

Participation in agricultural cooperative organizations is an important form of industrial chain organization expansion, but also an important way to effectively reduce industrial chain transaction costs and promote the quality and efficiency improvement of new agricultural business *** on the micro-survey data of 553 family farms in Xinjiang Corps in 2021, this paper uses stochastic frontier approach to measure the business performance of family farms in Xinjiang Corps, and discusses the action mechanism and difference in the influence of participation in agricultural cooperative organizations on the business performance of family farms. The research shows that participation in agricultural cooperative organizations can significantly improve the business performance of family farms through such mechanisms as easing the constraints of farm credit financing, reducing the transaction costs of agricultural products, and promoting the adoption of agricultural technologies. Compared with food farms, cotton and fruit and vegetable family farms have more obvious performance improvement in participating in agricultural cooperative organizations. Moreover, participation in agricultural cooperation organizations has a stronger effect on the performance improvement of farms in northern Xinjiang. It is found that the vertical extension of the industrial chain between”family farm+agricultural cooperative organization” and network marketers, chain supermarkets, industrial leading enterprises and agricultural production and marketing enterprises is conducive to the improvement of the business performance of family farms, among which the performance improvement effect of”family farm+agricultural cooperative organization+network marketers” mode is more obvious. The research provides a scientific reference for deepening the expansion of the industrial chain organization and promoting the quality-oriented growth of family farms in the new era.

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Auto-tuning PVT data using multi-objective optimization: Application of NSGA-Ⅱ algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi Mohammad Madani Mohammad Jafarzadegan Reservoir engineering Systems Petroleum Engineering Department Main Office Building of National Iranian South Oil Company (NISOC) Combined Planning management National Iranian Oil Company (NIOC) Reservoir engineering division Petroleum Engineering Department Petroleum Engineering and Development Company (PEDEC)

Reservoir simulation is known as perhaps the most widely used, accurate, and reliable method for field development in the petroleum industry. An integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS models. Traditionally, EOS models are tuned iteratively through arduous workflows against experimental PVT data. However, this comes with a number of drawbacks such as forcingly using weight factors, which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective optimization. In order to illustrate the robustness of the presented technique, three different PVT samples are used, including two black-oil and one gas condensate sample. We utilize PengRobinson EOS during all the manual and auto-tuning processes. Comparison of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is robust. In addition, the proposed method, contrary to the manual matching process, provides the engineer with several matched solutions, which allows them to select a match based on the engineering background to be best amenable to the problem at hand. In addition, the proposed technique is fast, and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Assessment of the Influence of Tunnel Settlement on Operational Performance of Subway Vehicles

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Structural Durability & Health Monitoring 2024年第1期18卷 55-71页

作者： Gang Niu Guangwei Zhang Zhaoyang Jin Wei Zhang Xiang Liu China Communications construction Rail Transit Subsidiary Beijing100000China China Communications construction Strait construction Investment Development Co. Ltd.Fuzhou350000China School of Civil engineering Fujian University of TechnologyFuzhou350118China

In the realm of subway shield tunnel operations,the impact of tunnel settlement on the operational performance of subway vehicles is a crucial *** study introduces an advanced analytical model to investigate rail geometric deformations caused by settlement within a vehicle-track-tunnel coupled *** model integrates the geometric deformations of the track,attributed to settlement,as track irregularities.A novel“cyclic model”algorithm was employed to enhance computational efficiency without compromising on precision,a claim that was rigorously *** model’s capability extends to analyzing the time-history responses of vehicles traversing settlement-affected *** research primarily focuses on how settlement wavelength,amplitude,and vehicle speed influence operational *** findings indicate that an increase in settlement wavelength can improve vehicle performance,whereas a rise in amplitude can degrade *** study also establishes settlement thresholds,based on vehicle operation comfort and *** insights are pivotal for maintaining and enhancing the safety and efficiency of subway systems,providing a valuable framework for urban infrastructure management and long-term maintenance strategies in metropolitan transit systems.

关键词： Settlement running performance subway tunnel dynamic analysis track irregularity threshold

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng CHEN Jie CHEN Xunchang John ZHANG Peiyi PENG State Key Laboratory of Water Resources engineering and management Wuhan University Hubei Key Laboratory of Water System Science for Sponge City construction Wuhan University USDA-ARS Oklahoma and Central Plains Agricultural Research Center Southwest Research Institute for Hydraulic and Water Transport engineering Chongqing Jiaotong University

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***, accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in China. In this study, a data fusion method based on Convolutional Neural Networks（CNN） is used to fuse the hydrogen isotopic composition（δ2Hp） of observations and isotope-equipped general circulation model（iGCM） simulations. A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50–60 km is established for East China for the 1969–2017 period. Prior to building the isoscape, the performance of three data fusion methods（DFMs） and two bias correction methods（BCMs） is compared. The results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a benchmark. The fusion methods based on back propagation and long short-term memory neural network perform similarly, while slightly outperforming the bias correction methods. Thus, the CNN method is used to generate the hydrogen isoscape, and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this dataset. The generated isoscape shows similar spatial and temporal distribution characteristics to observations. In general, the distribution pattern of δ2Hpis consistent with the temperature effect in northern China, and consistent with the precipitation amount effect in southern China. The trend of the δ2Hptime series is consistent with that of observed precipitation and temperature. Overall, the generated isoscape effectively reproduces the observations, and has the characteristics of time continuity and relative spatial regularity, which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

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engineering classification recycling of spent lithium-ion batteries through pretreatment:a comprehensive review from laboratory to scale-up application

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Rare Metals 2024年第3期43卷 915-941页

作者： Shu-Xuan Yan You-Zhou Jiang Xiang-Ping Chen Lu Yuan Ting-Ting Min Yu Cao Wan-Li Peng Tao Zhou Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China College of Chemistry and Chemical engineering Hunan Normal UniversityChangsha 410083China School of Public Policy and management Tsinghua UniversityBeijing 100084China China Nonferrous Metal Industry's Foreign engineering and construction Co. LtdBeijing 100029China

The lithium-ion batteries(LIBs)have been widely equipped in electric/hybrid electric vehicles(EVs/HEVs)and the portable electronics due to their excellent electrochemical ***,a large number of retired LIBs that consist of toxic substances(e.g.,heavy metals,electrolytes)and valuable metals(e.g.,Li,Co)will inevitably flow into the waste stream,and their incineration or landfill treatment will cause severe risks to ecosystem and human *** sustainable and efficient treatment or recycling of valuable resources from spent LIBs should be fully recognized for environmental and resource *** one of the most important processes for spent LIBs recycling,the pretreatment is an indispensable step,which is directly related to the subsequent metal extraction and separation *** considerable progresses have been made regarding the pretreatment technologies,there are few summarized reports concerning critical processes of spent LIBs recycling,especially combination of currently available recycling technologies with industrialized applications during ***,comprehensive review of the current prevailing pretreatment technologies in laboratory to existing scale-up applications is quite necessary to reveal cutting-edge development in the field of *** this review,the current pretreatment technologies are systematically categorized and introduced,along with critical *** review focused on the various options for pretreatment processes itself,instead of general spent LIBs recycling technologies without the focused topics that have been sophisticatedly reviewed by previous ***,the deactivation,discharge,dismantling,separation,liberation of active material and electrolyte treatment have been summarized with the in-depth discussion of the technology development and current status of each ***,current states of industrial development are also reviewed and discussed for the development of

关键词： Spent lithium-ion batteries(LIBs) Recycling Pretreatment Valuable metals Cutting-edge technologies Industrialized application

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Mechanical properties and energy evolution of Beishan shallow-layer granite under different unloading paths

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Journal of Mountain Science 2024年第5期21卷 1728-1744页

作者： WANG Chuanle LI Erbing ZHANG Dengke HAN Yang LU Hui HE Kang DU Guangyin School of Transportation Southeast UniversityNanjing 211189China College of Defense engineering Army Engineering University of PLANanjing 210007China Nanjing Urban construction management Group Co. Ltd.Nanjing 210006China College of Field engineering Army Engineering University of PLANanjing 210007China

Rock has mechanical characteristics and a fracture damage mechanism that are closely related to its loading history and loading path. The mechanical properties, fracture damage features, acoustic emission(AE) characteristics, and strain energy evolution of the Beishan shallow-layer granite used in triaxial unloading tests were investigated in this study. Three groups of triaxial tests, namely, conventional triaxial compression test(Group Ⅰ), maintaining deviatoric stress synchronously unloading confining pressure test(Group Ⅱ), and loading axial pressure synchronously unloading confining pressure test(Group Ⅲ), were carried out for the cylindrical granite specimens. AE monitoring device was utilized in these tests to determine the degree to which the AE waves and AE events reflected the degree of rock damage. In addition, the crack stress thresholds of the specimens were determined by volumetric strain method and AE parameter method, and strain energy evolution of the rock was explored in different damage stages. The results show that the shallow-layer granite experiences brittle failure during the triaxial loading test and unloading test, and the rock has a greater damage degree during the unloading test. The crack stress thresholds of these samples vary greatly between tests, but the threshold ratios of all samples are similar in the same crack damage stage. The Mogi-Coulomb strength criterion can better describe the unloading failure strength of the rock. The evolution of the AE parameter characteristics and strain energy differs between the specimens used in different stress path tests. The dissipative strain energy is the largest in Group Ⅱ and the smallest in Group Ⅰ.

关键词： Beishan granite Unloading test Mechanical properties Damage mechanism Acoustic emission Strain energy

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