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Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Jinan is an important city in eastern China, with rich groundwater in the region. There are four famous springs in the urban area and an abundance of geothermal water in the northern part, which makes the migration of groundwater in this area a very important issue. To study the shallow shear wave velocity structure and groundwater migration in Jinan, we utilized almost a month of continuous waveform data from 175 short period seismometers deployed by the Chinese Academy of Geological Sciences, in order to calculate the cross‐correlation function. We picked 7749 group dispersion curves and 6117 phase dispersion curves with a period range of 0.2–2 s. Through inversion, we obtained the fine three‐dimensional shear wave velocity and azimuthal anisotropy structure (0–2.4 km). Combining the results with local geological and hydrological data, the following conclusions were reached. (1) There are widespread high velocity anomalies in the region between the Qianfoshan and Wenhuaqiao faults, as well as to the east of the Wenhuaqiao Fault, which may be related to the intrusive gabbro known as the Jinan Intrusive Rock. (2) The two distinct high velocity anomalies in our model (referred to as west and east Jinan Intrusive Rock in this paper) may indicate that the Jinan Intrusive Rock was broken through crustal movement. (3) There is an obvious low velocity layer under the intrusive rock, which could be the channel of groundwater migration. The precipitation in the southern mountain region seeps down into the ground, then is blocked by the Jinan Intrusive Rock and can only progress downwards to a deeper part, where the groundwater is heated by the geothermal gradient. The heated water finally arrives at the northern part and forms geothermal water. (4) The depth of the low velocity layer beneath the Jinan Intrusive Rock varies laterally, which may indicate that the depth of the groundwater migration is different beneath the west and east Jinan Intrusive Rock. (5) There is strong azimuthal anisotropy in southern Jinan, with nearly E‐W fast orientation, which may be related to the tilt limestone layering structure. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mining cities in China have long faced pressures such as the occupation of urban land by waste discharge from mining areas, the harsh ecological environment, and the surge in unemployment. After years of exploration, the development of urban underground space is the best way to solve the above problems. Based on the geological condition and urban planning condition of Tangshan City, this paper put forward the concept of underground space development, and chose underground space waste storage and utilization methods according to local conditions. It analyzed the distribution of underground space in Tangshan City and its corresponding surface conditions, and calculated the volume of underground space as 9.1 × 107m3; proposed the concept of utilization efficiency of underground space, established the deformation model of underground space surrounding rock, and calculated the reasonable width of waste storage space. The width is about 60 m, and the space utilization efficiency should reach 82%; based on the field practice of the waste storage project, the measured space utilization efficiency is 73%, which is slightly less than the theoretical calculation value; Through the urban surface deformation and air monitoring, the underground waste storage project in Tangshan City is successful. The negative effect of urban ground is relatively small, and it is the best method suitable for the utilization of underground space in China's mining cities, and provides a theoretical basis for the development of urban underground space in China. [ABSTRACT FROM AUTHOR]

[Display omitted] • We designed an underground logistics system (ULS) for last mile delivery. • The last-mile delivery system (LDS) of ULS has two mode categories: "self-pickup +" and "home-entry +". • It enabled express parcel delivery at the city, regional, and neighborhood levels. • The system was validated in an urban sub-center in China. Underground logistics systems (ULSs) are emerging low-carbon, energy-saving, and ground-space-saving logistics and transportation approaches that rely on underground tunnels/pipelines for freight transportation. Thus, they will effectively solve the urban logistics dilemma caused by the rapid growth of express parcel volumes in China, especially concerning last-mile delivery in cities, which is currently one of the most expensive and least efficient parts of the entire logistics and transportation process. We designed a three-level (i.e., city, regional, and neighborhood) last-mile delivery system (LDS) for express parcel transportation according to a metro-based ULS (M − ULS). We categorized the LDS into two modes: "self-pickup +" and "home-entry +." According to different needs, we then applied the system to five different scenario–mode combinations: "self-pickup + metro stations," "self-pickup + shopping malls," "self-pickup + communities," "home-entry + communities," and "home-entry + office buildings." Finally, using an urban sub-center in China as a case study, we analyzed efficiency and emission reduction of LDS in the five scenario–mode combinations with different freight volumes and verified the validity of the proposed system. This system has great potential for solving last-mile delivery challenges and provides new ideas and technical solutions for planning and designing future ULSs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ecological benefits of using urban underground space (UUS) needs evaluation. • CO 2 sequestration efficiency is estimated to assess ecological potential of UUS. • CO 2 sequestration caused by UUS was 7% of emissions by construction industry. • UUS enables construction of blue–green spaces toward achieving carbon neutrality. Urban carbon sinks from plant photosynthesis in urban blue-green spaces (BGSs) effectively sequester CO 2 and achieve carbon neutrality. Building urban facilities underground saves land for the development of urban BGSs. Development and utilization of urban underground space (UUS) is increasing rapidly in most advanced cities globally, many of which are located in China. This study combined the planting design strategy of urban BGS and the vegetation carbon sequestration efficiency estimation method to quantitatively assess the ecological carbon sink potential of the use of UUS. Three types of BGSs: partly open green space (GPO), closed green space (GC), and partly open blue space (BPO), were first constructed based on their practicability in the city, and a planting strategy was designed for urban BGSs accordingly. Secondly, a model for the conversion of UUS development intensity into surface space to achieve ecological carbon sinks under three scenarios of UUS development intensity (low, medium, and high intensity) was constructed. Thirdly, methods for the calculation of carbon sequestration by GPO, GC, and BPO, were established based on the land-use carbon emission model. The developed method was finally validated through a case study in the Tianfu New District Directly Administered Area of Chengdu in Sichuan Province, China. The results of the study in Chengdu show that the higher the intensity of the use of UUS, the greater the proportion of carbon sink contribution to the CO 2 emissions of the building industry for the planned population, and a maximum of 7% of carbon emissions absorbed from the building industry for the planned population was achieved. These findings serve as a reference for assessing the use of UUS to achieve urban carbon neutrality in other cities. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper mainly reviews the history of the construction of the underground utility tunnel in China, and points out the existing problems. Based on the analysis of several construction cases, some practical experience on the large-scale promotion and construction of urban underground utility tunnels in China are given from the decision-making, planning, construction, management and other aspects, which may be helpful to the development of underground utility tunnels in other countries. [ABSTRACT FROM AUTHOR]

Following economic growth and urban development in China in the past two decades, rapid urbanization have incurred many pronounced problems to many Chinese cities. Since 2000, key areas in many Chinese cities, drawing on valuable urban development experience from America and European countries, flock to conduct master planning of urban underground space (UUS) development. The compiling practice is conducive to the orderly development of urban space and alleviation of increasing human-land conflicts. Through selecting and analyzing the master planning UUS in Qingdao, this paper first investigates the current problems of UUS development and utilization in China, and then analyzes the planning methods and general thoughts of overall underground space layout. In general, the paper presents some current advanced research findings in the master planning of UUS development in China. [ABSTRACT FROM AUTHOR]

• A MAS- based model of UUS development was developed. • A model for intertemporal allocation of UUS resource was presented. • The UUS development decision-making rules were defined. • The process of UUS development was well described, interpreted, and predicted. The development of urban underground space (UUS) serves to promote the intensive use of land resources, overcome the shortage of space resources, and achieve sustainable urban development. Since UUS development is a dynamic and complex process involving diverse stakeholders, investigating its operating mechanisms and predicting its trajectory is crucial to achieve sustainable urban development. This study used a multi-agent system modeling method to build a UUS development decision-making model for exploring the interactions between different stakeholders and their adaptive decision-making behaviors. The model allows the dynamic UUS development process to be presented spatially, considering the spatiotemporal changes in environmental, economic, and social factors. The actual status and three future scenarios of UUS development were simulated and analyzed for the Yanling business district of Changzhou City, China. The simulation results show that the model can effectively describe, interpret, and predict the dynamic spatiotemporal process of UUS development, thereby providing theoretical reference and decision-making support for UUS planning and policymaking. [ABSTRACT FROM AUTHOR]

• The methods of MCDA and complex networks are combined to yield an E-CN-TOPSIS model. • The dimensions of hazard, exposure, vulnerability and resilience is considered. • A dataset of real cases is used to construct the UUS risk chain. • We assessed geospatial unbalance in the UUS risk across cities based on data. • GBA has the highest UUS risk level among the three major economic circles in China. With the acceleration of urban development, the urban underground space (UUS) begins to show the characteristics of a complex giant system. In most of the traditional risk assessment frameworks, metrics are developed by treating the object as a whole. There is a lack of applicable objective-based assessment methods when there are correlations and network structures among the internal structures of the object. Here we propose and test a method, a comprehensive risk assessment model E-CN-TOPSIS applicable to UUS, to solve this problem. First, an initial risk assessment framework with 4 primary indicators and 30 sub-indicators was proposed based on Multi-Criteria Decision Analysis (MCDA). Second, a risk chain analysis network of UUS containing 201 risk nodes based on real cases was constructed. The principal component analysis method was taken to quantify the chain-coupled risk mechanism of multi-facility within UUS to integrate the external risk assessment framework with the internal risk chain network. Then we analyzed 16 main cities in three major economic circles of China. Our analyses indicate that 'Recovery capability' was the priority in all evaluation indicators. The main factors influencing the UUS risk in three major economic circles are management policies. The UUS risk is highest in Greater Bay Area, followed by Jing-Jin-Ji, and Yangtze River Delta. Finally, some outlooks and suggestions are given. By applying this methodology, useful information can be provided for the fine planning and precise prevention of new complex UUS risks. [ABSTRACT FROM AUTHOR]

• Framework of UUS geological suitability evaluation in 3D (3D-UGSE) is proposed. • Implicit method enables fast automatic generation of underground geological bodies. • 3D spatial analysis methods extract more evaluation factors via data integration. • 3D-UGSE framework gives more evaluation results and enhances down-depth resolution. Geological suitability evaluation for urban underground space (UUS) is essential for effective UUS utilisation and exploitation risk reduction. However, previous research was hampered by limited availability of 3D technology. The 2D data-based evaluation process has led to information loss among underground data, whilst evaluation results without 3D attributes would also impede accurate analysis and further application. This study presents a novel UUS geological suitability evaluation (3D-UGSE) framework, which accounts for the characteristics of 3D data and other practical requirements. The framework integrates a large amount of available geoscientific data with 3D technology, and contains five steps: (1) data collection and integration; (2) 3D geological model construction using implicit 3D geological modelling method with multi-source geological data; (3) 3D evaluation index system creation, considering local geological conditions based on the available data; (4) 3D thematic map production from the 3D geological models, using 3D spatial analysis methods; (5) 3D geological suitability map production, integrating all the 3D thematic maps using comprehensive evaluation methods. To evaluate this approach, we took the Qianjiang Newtown in Hangzhou (eastern China) as an example and assessed the UUS geological suitability in three dimensions. The results show that the 3D-UGSE framework can effectively integrate 2D and 3D geological information, give more reasonable and informative evaluation results, and enhance the depth resolution of the results. This approach can provide more useful information for the planning, sustainable development, and utilisation of urban underground space. [ABSTRACT FROM AUTHOR]