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Journal of Energy Chemistry 2025年第1期100卷 621-627页

作者： Fei Lv Longjie Liu Jiazhe Wu Pengfei Wang Lixia Pan Dengwei Jing Yubin Chen International research center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen （H2） and ***,the design and development of such systems is still in its ***,an integrated hydrogen-oxygen （O2）-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate （NaNiHCF） and Zn2+/Zn as dual redox *** decoupled electrolyzer enables to produce H2and O2in different time and space with almost 100%Faradaic efficiency at 100 mA ***,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A *** connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.

关键词： Hydrogen Electricity Decoupled water electrolyzer Na-Zn ion battery Solar energy

Evaluation of the effects of EPS composite soil replacement on the dynamic performance of caisson structure using shaking table tests

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 829-843页

作者： Gao Hongmei Ji Zhanpeng Zhang Xinlei Zhang Shushan Wang Zhihua Shen Guangming research center of urban underground space Nanjing Tech UniversityNanjing 211816China Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 211816China

The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table *** macro phenomena of the two different foundation models are described and *** effects of the replacement of EPS composite soil on seismic-induced liquefaction of backfill and the dynamic performance of a caisson structure are evaluated in *** results show that the excess pore water pressure generation in the CES is significantly slower than that in the CSS during the *** dynamic earth pressure acting on the caisson has a triangular *** response of horizontal acceleration,displacement,settlement,and rotation angle of the caisson in the CES is smaller than that in the CSS,which means the caisson in the CES has a better seismic ***,the out-of-phase phenomenon between dynamic earth thrust and inertial force in the CES is more obvious than that in the CSS,which is beneficial to reduce the lateral force and improve the stability of the caisson structure.

关键词： EPS composite soil foundation Caisson-type quay wall shaking table test phase difference rotation angle

Cyclic constitutive equations of rock with coupled damage induced by compaction and cracking

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International Journal of Mining Science and Technology 2022年第5期32卷 1153-1165页

作者： Chonghong Ren Jin Yu Xueying Liu Zhuqing Zhang Yanyan Cai Fujian research center for Tunneling and urban underground space Engineering Huaqiao UniversityXiamen 361021China Xiamen Rail Transit Group Corporation Limited Xiamen 361021China

In this paper,the cyclic constitutive equations were proposed to describe the constitutive behavior of cyclic loading and ***,a coupled damage variable was derived,which contains two parts,i.e.,the compaction-induced damage and the cracking-induced *** compaction-induced damage variable was derived from a nonlinear stress–strain relation of the initial compaction stage,and the cracking-induced damage variable was established based on the statistical damage ***,based on the total damage variable,a damage constitutive equation was proposed to describe the constitutive relation of rock under the monotonic uniaxial compression conditions,whereafter,the application of this model is extended to cyclic loading and unloading *** validate the proposed monotonic and cyclic constitutive equations,a series of mechanical tests for marble specimens were carried out,which contained the monotonic uniaxial compression(MUC)experiment,cyclic uniaxial compression experiments under the variable amplitude(CUC-VA)and constant amplitude(CUC-CA)*** results show that the proposed total damage variable comprehensively reflects the damage evolution characteristic,i.e.,the damage variable firstly decreases,then increases no matter under the conditions of MUC,CUC-VA or *** a reasonable consistency is observed between the experimental and theoretical *** proposed cyclic constitutive equations can simulate the whole cyclic loading and unloading behaviors,such as the initial compaction,the strain hardening and the strain ***,the shapes of the theoretical curves are controlled by the modified coefficient,compaction sensitivity coefficient and two Weibull distributed parameters.

关键词： Cyclic constitutive equations Rock Coupled damage Compaction Cracking

Quantitative evaluation of the contribution of underground space to urban resilience:A case study in China

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underground space 2024年第4期17卷 1-24页

作者： Si-Cong Liu Fang-Le Peng Yong-Kang Qiao Yun-Hao Dong research center for underground space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

urban underground space(UUS)development has been acknowledged as a positive contribution to urban resilience(UR).Such contribution has been qualitatively addressed in recent years,but only quantitatively discussed in few *** evaluation methods for UR are widely used in China and around the world,but the role of underground space is barely *** paper provides a way to bridge this gap on the city scale.A UR evaluation framework was carefully constructed that covers the basic aspects and elements of *** contributions of UUS to UR were identified and integrated into the UR evaluation framework,and the measurement methods for each indicator related to UUS were determined.A case study of 19 sample cities in China were conducted using the integrated evaluation *** analysis and clustering analysis were further adopted to interpret the evaluation results,mainly with three indicators reflecting the level of UUS development,namely UUS area(m^(2)),UUS density(104 m^(2)/km^(2))and UUS area per capita(m^(2)/person).The results showed a strong correlation between UUS area and *** average proportion of UR provided by UUS in the 19 sample cities was 16.46%,while the maximum figure reached 29.20%.The sample cities were clustered into four categories based on the relationship between the proportion of UR provided by UUS,UUS area,and GDP per capita,where both high and low UUS area tend to provide less proportion of resilience than the medium UUS *** suggestions for UUS utilization were proposed to assist cities in achieving urban resilience.

关键词： urban underground space(UUS) urban resilience Resilience evaluation Resilient development

Planning an adaptive reuse development of underutilized urban underground infrastructures:A case study of Qingdao,China

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underground space 2024年第1期14卷 18-33页

作者： Yong-Kang Qiao Fang-Le Peng Yun-Hao Dong Chun-Fang Lu research center for underground space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

urban underground infrastructures(UUIs)are a vital component of built capital for urban ***,many cities are now home to a multitude of disused or underutilized UUIs,not least aged purpose-built underground facilities,causing a waste of valuable underground space resource *** the process of urban renewal,adaptive reuse can be an attractive solution to breathe new life into underutilized UUIs,while addressing some of the modern problems of the built environment by an economically feasible ***,there is a prevalent absence in the current literature of the overarching planning and decision-making approaches for an adaptive reuse development of underutilized *** the intention of addressing this shortfall,this paper first lays out development strategies,then sets the generic patterns for adaptive reuse of disused or underutilized *** the city of Qingdao,China as a case study,detailed planning and decision-making approaches with the aid of multi-source data and spatial analysis tools are *** is anticipated that the findings of this research will assist the adaptive reuse development of UUIs in providing theoretical guidance and empirical evidence,thereby enhancing the role of urban underground space use in contributing to urban revitalization and urban sustainability.

关键词： urban underground infrastructures Underutilized Adaptive reuse Planning urban renewal

Propagation characteristics of vibration waves induced in surrounding rock by tunneling blasting

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Journal of Mountain Science 2017年第12期14卷 2620-2630页

作者： chen shi-hai hu shuai-wei zhang zi-hua wu jian Huaqiao University Xiamen 361021China Fujian research centerfor Tunneling and urban underground space Engineering Huaqiao UniversityXiamen 361020China

The effect of blasting vibration waves on surrounding rock and supporting structures is an important field in underground engineering. In this paper, the separation variable method is used to solve the displacement potential function for the propagation of the blasting vibration waves. In the axis coordinate system, the particle motion and stress change with axial distance, radial distance and time is obtained in surrounding rock. The peak particle velocity law in surrounding rock under different blast loads and surrounding rock parameters is *** addition, the particle vibration characteristics in the surrounding rock are studied using numerical simulations method. The results shows that the peak particle velocity in surrounding rock appears negative exponent attenuation with the increase of axial distance, but it appears positive and negative fluctuations in radial direction. This phenomenon is a new discovery and it has been rarely investigated before. Moreover, the peak particle velocity attenuates more quickly and intensely in the near blasting field,which means that the supporting structure in a shorter distance away from the heading face is vulnerable to the impact of blasting vibration. Theattenuation of blasting vibration velocity is closely related to charge length, blasting load amplitude,attenuation index and rock elastic modulus. The numerical simulation accomplishes the same results and then demonstrates the validity of theoretical results.

关键词： Tunneling blasting Blasting vibration wave Surrounding rock Wave equation Vibration velocity

Geomechanical design of a room and rib pillar granite mine

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Journal of University of Science and Technology Beijing 2008年第2期15卷 97-103页

作者： Daniele Peila Claudia Guardini Sebastiano Pelizza Tunnelling underground space center Department of EnvironmentLand and Geotechnology Engineering Politecnico di Torino Tunnelling underground space center Department of EnvironmentLand and Geotechnology EngineeringPolitecnico di TorinoTorinoItaly

The geomechanical and stability design of an underground granite mine located in Canal San Bovo （Trento district, Northeastern Italy） was described. The exploitation of the granite, which is used in the ceramic industry, was carried out by the rooms and rib pillars method. The rooms are 12 m wide while the pillars are 11 m wide and they cross the main discontinuity set of the rock mass in the perpendicular direction. To verify the stability condition of an underground mine, it is necessary to carry out the calcula- tions that are able to check both the local and global stability of the rock mass. In the studied example, this approach has been applied with the development of analytical and numerical parametric analyses and it has permitted to get the best orientation and to design the size of rooms and pillars.

关键词： mining room and pillar rock mechanics stability analysis

Theoretical analysis of JMC effect on stress wave transmission and reflection

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1237-1245页

作者： Xin Chen Mei-feng Cai Jian-chuan Li Wen-hui Tan Beijing Key Laboratory of urban underground space Engineering University of Science and Technology Beijing Civil and Resource Engineering School University of Science and Technology Beijing Institute of underground space Technology School of Civil EngineeringSoutheast University

Taking the joint matching coefficient(JMC) which represents the contact area ratio of the joint in rock masses as the key parameter, a one-dimensional contacted interface model(CIM-JMC) was established in this study to describe the wave propagation across a single joint. According to this model, the reflected and transmitted waves at the joint were obtained, and the energy coefficients of reflection and transmission were calculated. Compared with the modified Split Hopkinson pressure bar(SHPB) experiment, it was validated by taking the incident wave of the SHPB test as the input condition in the CIM-JMC, and the reflected and transmitted waves across the joint were calculated by the model. The effects of four sets of JMCs(0.81, 0.64, 0.49, and 0.36) on the transmission and reflection of the stress wave propagation across the joint were analyzed and compared with the experimental results. It demonstrated that the values of CIM-JMC could represent both the transmission and reflection of the stress wave accurately when JMC > 0.5, but could relatively accurately represent the reflection rather than the transmission when JMC 0.5.

关键词： joint matching coefficient stress wave transmission reflection energy coefficient rock dynamics

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and space Sciences University of Science and Technology of China Institute of Deep space Sciences Deep space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Wear mechanism and life prediction of the ripper in a 9-m-diameter shield machine tunneling project of the Beijing new airport line in a sand-pebble stratum

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Deep underground Science and Engineering 2022年第1期1卷 65-76页

作者： Hua Jiang Jiachen Zhu Xiaoyan Zhang Jinxun Zhang Hongliang Li Lingfeng Meng Department of urban underground space School of Mechanics and Civil EngineeringChina University of Mining and TechnologyBeijingChina Post-Doctoral research center Beijing Urban Construction Group Co.Ltd.BeijingChina

Tool wear is a noteworthy problem in the process of shield tunneling,and the degree of wear varies with *** sand-pebble strata in Beijing are typically mechanically ***,many subways are buried wholly or partially in sand-pebble *** the Beijing New Airport line tunneling project as research background,this study evaluated the wear characteristics of the multiconfiguration rippers of a 9-m-diameter spoke-type shield tunneling machine in a sand-pebble *** wear values of five ripper teeth and ripper flanks were analyzed based on field-measured data from the Beijing New Airport line *** the analytical results show,the wear value generally increases as the installation radius enlarges with the rise of cutting trace *** wear of the 190-rippers was divided into five categories:pedestal wear,ripper teeth collapse,uniform wear,ripper teeth falling off and ripper flank *** wear of the ripper teeth and ripper flank wear were the two abrasion types of the *** teeth of the 155-rippers mostly maintained their cutting capacity under the protection of the 190-rippers.A wear prediction model of linear fitting field data was developed for a 190-ripper face to obtain the optimum shield driving distance in the sand-pebble *** average wear coefficients of the 190-ripper before and after replacement matched well,being 0.045 and 0.066 mm/km,*** results of this study provide a theoretical reference for tool wear prediction in shield construction under similar geological conditions.

关键词： 9-m-diameter shield long-distance shield driving optimum driving distance sand-pebble stratum tool wear wear prediction model