Underground Space Planning Research Articles

3D modelling of subsurface legal spaces and boundaries for 3D land administration

The increasing trend of urbanization results in various problems regarding enabling the livable cities such as traffic congestion, environmental pollution, and inadequate disaster preparedness. These problems are considerably related to deficiencies in the aboveground usable areas that can be exploited for the development of urban areas. Underground development is one of the strong solutions to cope with the aforementioned problems. The holistic planning of underground space is an important factor in ensuring the efficient use of underground space. Land administration that deals with the cadastral rights, restrictions, and responsibilities (RRRs) on the surface and subsurface is highly significant in the context of planning the underground space. By nature, there is a need for three-dimensional (3D) ownership information below the surface in order to carry out the analyses within planning studies regarding different aspects such as the existing subsurface structure and environmental impacts. This paper therefore enriches the core data model of the CityJSON standard such that it allows for 3D modelling of legal spaces and boundaries in the subsurface. It presents the usability of the proposed extension by visualizing the underground cadastral RRRs in 3D through the created and validated CityJSON file based on this extension. The practical opportunity arising from the use of CityJSON files derived from the developed extension is demonstrated. Different case studies are presented including the compliance checking regarding the designed underground tunnel within building permitting. The results of this study show that integrated 3D land administration including subsurface can contribute to the facilitation of the overarching planning of underground space.

Three-Dimensional Quality Assessment of Urban Underground Space Resource Based on Multiple Geological Environmental Factors

With the rapid advancement of urbanization, the development and utilization of urban underground space resource (UUSR) has become one of the dominant features. However, in certain areas, the development of UUSR may cause disasters and accidents, such as ground collapse, settlements, and tunnel water gushing. Geological environmental factors (GEFs) are recognized as the fundamental constraining factor of UUSR development. In this paper, quality based on GEFs is defined to assess the development difficulty degree of UUSR. A 3D assessment framework is proposed based on 3D geological modelling and the interval continuous mathematical model (ICMM). The subjective and objective joint weight method of analytic hierarchy process and entropy weight method (AHP–EWM) is utilized to determine the weight of each indicator. The quality index (QI) of each spatial node of the 3D geological model is calculated by the ICMM mathematical model. A case study conducted in the Jiangbei New District of Nanjing, China, serves as a demonstration of the UUSR assessment. The results clearly illustrate the 3D distribution characteristics of the quality in the study area, offering valuable insights for future 3D urban underground space planning.

A data-informed assessment method for the urban underground complex vitality

The urgent need for urban renewal and the rapid expansion of underground spaces has spurred the construction of urban underground complexes (UUCs). Vibrant UUCs are crucial for the efficient utilization of underground spaces and urban sustainability. Previous research on urban underground complex vitality (UUCV) has been primarily theoretical with limited reusability. In this study, we aimed to address this gap by focusing on underground functional facilities and spatial distribution characteristics to establish a UUCV indicator system based on walkability theory. We introduced a method based on exponential weighted mean for weight allocation to facilitate vitality calculations. Using the Wujiaochang UUC in Shanghai as a case study, we explored the spatial distribution mechanism of vitality and validated the feasibility of this research framework. The proposed assessment method and results obtained in this study offer valuable insights into underground space planning and design, particularly in the context of urban renewal.

Cluster analysis of underground space in the core area of new districts from the perspective of urban morphology

Extensive underground space development worldwide has significantly contributed to the sustainability of social, ecological, and economic growth. In view of the tendency towards haphazard urban sprawling during the development of new areas in China, underground spaces have been increasingly utilized to create sustainable and resilient urban built environments. However, insufficient attention has been paid to their morphological characteristics, resulting in a lack of sustainable and resilient underground space morphological planning and design techniques. To bridge this gap, we established a computational morphology indicator system pertaining to underground spaces, considering land use, spatial distribution, and street networks. We selected 20 underground spaces in well-developed core areas of new districts in China. Hierarchical cluster analysis was adopted to investigate the morphological features of underground spaces. Additionally, the typology of underground space morphology and the corresponding characteristics were systematically summarized to facilitate decision-making for different patterns of underground space planning.

Influencing factors of spatial vitality in underground space around railway stations: A case study in Shanghai

Developing urban underground space for transportation and commercial purposes has become a vital strategy for sustainable urban growth, especially in dense urban contexts. The vitality of underground space has received wide attention as a key indicator of its efficiency and performance. The spatial vitality of underground space is affected by many factors, including function, spatial configuration, transport environment, and pedestrian-oriented design features. This study takes the underground space of Shanghai Hongqiao Business District (Phase I), one of the most successful integrated railway station-city development projects, as a case to explore the spatial and temporal distribution characteristics of spatial vitality and its influencing factors. Multilevel linear models were used to analyze the relationship between pedestrian flow and its influencing factors. Random forest models were used to investigate the relative importance of influencing factors on spatial vitality. This study verified that the distance to the transportation hub and spatial configurations calculated by space syntax are the two most essential factors for vitality. The number of retail stores and walkway width impact the vitality on weekends. The results shed light on our understanding of the urban vitality in the underground space and provide some tentative suggestions for the planning and design of underground space in high-density cities.

3D UNDERGROUND LAND ADMINISTRATION BY STANDARDIZED GEOINFORMATION

Abstract. The density of the built environment is growing due to the migration from rural areas to urban areas. The challenges that should be addressed are therefore increased in today’s built environment. In relation to this, the productive use of underground space is essential to overcome the problems on the surface. Since the built environment has complex and multi-layered buildings more than ever, the delineation and management of the cadastral rights, restrictions, and responsibilities (RRRs) are significantly difficult in two-dimensional (2D). For this reason, creating approaches for the efficient representation of RRRs in three-dimensional (3D) is a hot topic in recent years. Considering the multifaceted structure of the underground, 3D geoinformation regarding the underground is needed for managing the underground space. Regarding this, it is significant to underline that legal and administrative namely land administration considerations are integral parts of the planning of underground space. This paper thus extends the CityJSON core schema in a way that it can be used for 3D delineation of underground cadastral RRRs.

A Methodology of Comprehensive Quality Evaluation for the Underground Space

AbstractUnderground space resources are very important for the purposes of urban sustainable develop Underground space resources are very important for the purposes of urban sustainable development and are an important way in which to realize three‐dimensional urban development. A reasonable and scientific evaluation of underground space resources is the basis for the rational use of land resources and urban planning. On the basis of the geological conditions concerned by predecessors, this study adds the analysis of the two influencing factors of social and economic value, existing facilities and protection needs. The evaluation index is quantified, and the comprehensive quality evaluation system of underground space resources is constructed. Finally, taking Nanshan District of Shenzhen as an example, the evaluation of underground space resources is carried out. The results show that for shallow underground space, the comprehensive quality of underground space resources development in Nanshan District is generally high. Nantou, Nanshan, and Yuehai streets are recommended to actively develop underground space, and Qianhai and Houhai areas are recommended to be cautious in the development and construction of underground space. In addition, this study also provide reference for the purposes of underground space planning in Nanshan District of Shenzhen.

Suitability Assessment of Multilayer Urban Underground Space Based on Entropy and CRITIC Combined Weighting Method: A Case Study in Xiong’an New Area, China

Suitability assessment is an essential initial step in the scientific utilization of underground space. It plays a significant role in providing valuable insights for optimizing planning and utilization strategies. Utilizing urban underground space has the potential to enhance the capacity of urban infrastructure and public service facilities, as well as mitigate issues such as traffic congestion and land scarcity. To effectively plan and utilize urban underground space, it is crucial to conduct a suitability assessment. This assessment helps identify the factors that influence the utilization of underground space and their impacts, offering guidance on avoiding unfavorable conditions and ensuring the safety of planned underground facilities. To achieve objective and reasonable evaluation results, this paper proposed an assessment method that combines entropy and CRITIC (CRiteria Importance Through Intercriteria Correlation) weighting. Taking Xiong’an New Area as a study area, a suitability assessment indicator system for underground space was established. The system included criteria indicators and sub-criteria indicators. By analyzing the weights, the study identified the difference of suitability and critical affecting factors for shallow, sub-shallow, sub-deep, and deep underground space. The results showed that deep layers had better suitability than shallow layers in the study area. The regions with inferior and worse suitability were mostly located around Baiyangdian Lake, with proportions of acreage at 54.69% for shallow layer, 42.06% for sub-shallow layer, 41.69% for sub-deep layer, and 42.03% for deep layer. Additionally, the dominant affecting factors of suitability varied in different layers of underground space. These findings provide valuable evidence for the scientific planning and disaster prevention of underground space in Xiong’an New Area, and also serve as references for studying suitability in other areas.

Planning urban underground space from urban emergency evacuation: A digital layout planning method

In recent years, the vulnerability of cities has heightened the threat of disasters, thereby endangering the safety of urban population. To mitigate these risks, the establishment of well-planned shelter system is of utmost importance for effective emergency response. Urban underground space (UUS) stands out as a promising solution for providing shelter during times of disasters, owing to its distinct characteristics of confinement and stability. However, the majority of UUS do not function directly for emergency evacuation, leading to neglect at the planning phase. It is valuable to study an applicable planning technique to prospectively consider emergency shelter services of UUS. In this paper, based on digital tools, a method for the rapid quantitative extraction and analysis of a dynamic population distribution is proposed to quantify demand for emergency evacuation. A multi-step greedy algorithm and a social force model (SFM) with specialized parameters are constructed to realize the simulation and analysis on a digital platform with integrated urban models. A multi-criteria decision-making system for evaluating UUS layout is established using the technique for order of preference by similarity to ideal solution (TOPSIS). Finally, a case study in Nanjing built-up area is presented to demonstrate the performance of the proposed method. The proposed method can expand the research perspective and data-driven toolkit for underground space planning.

A Comprehensive Study of the Suitability of Urban Underground Spaces for Connection Development: A Case Study of the Erhai Lake Basin, China

Urban underground space (UUS) involves multiple stakeholders whose concerns span the entire life cycle of underground space. The government pays more attention to the social benefits of UUS to the region, developers pay more attention to the economic benefits brought by the development of UUS, and users pay more attention to the comfort level of UUS operation. This study used the analytic Hierarchy Process (AHP), government, developers, and users to construct a comprehensive evaluation index system of underground space development needs. Different from previous studies, considering the need for future connectivity development in the UUS circle, this paper proposes to comprehensively consider the impact of connectivity development on regional suitability through coupled AHP and cellular automata (CA). The results show that about 102.67 km2 (13.03%) underground area of Erhai Lake Basin is suitable for underground space development. Compared with the traditional evaluation method, the evaluation result of about 31.41 km2 (3.99%) area was improved, and the fragmentation problem between blocks was improved. This method is of great value to the comprehensive development of UUS in the Erhai Lake Basin and is helping to improve future underground space planning.

Does the scarcity of urban space resources make the quality of underground space planning more sustainable? A case study of 40 urban underground space master plans in China

The international community has reached a consensus on promoting the sustainable development of global cities. As an important and irreversible space resource in a city, the development and utilization of urban underground space should follow the principle of sustainability and emphasize scientific and forward-looking planning. At present, most cities have formulated urban underground space master plans. However, due to the lack of an effective evaluation method, the plan quality is uneven, which directly affects the sustainability of underground space development and utilization. This paper proposes a set of sustainability evaluation framework of underground space planning based on relevant planning standards and plan quality evaluation protocol, and makes a comparative analysis of the 40 urban underground space master plans formulated in China from 2004 to 2020. The research found that the planning documents generally reflected the problem of emphasizing design strategies and engineering technology while neglecting implementation and humanistic care; administrative region, population density, land price and other variables closely related to the scarcity of urban space resources are the main factors affecting the quality of urban underground space planning. The conclusions of this paper can aid planners and researchers to identify the problems and influencing factors of underground space planning related to sustainability, and summarize the methods to improve the quality of underground space planning.

Evaluation of spatial performance and supply-demand ratios of urban underground space based on POI data: A case study of Shanghai

Master planning of urban underground space (UUS) is essential to guide orderly utilization of UUS. POI (point of interest) data from online maps provide a new data source for UUS research. This study proposed a simple framework to evaluate UUS development levels based on POI data. Evaluation methods of UUS spatial performance and development demand were established separately and then applied to the calculation of UUS supply-demand ratios of 217 sub-districts in Shanghai. The results showed that Huaihaizhonglu Sub-district achieved both the highest spatial performance and development demand values. The majority of the sub-districts with high or medium high performance values were situated in the central urban area. By comparison, the sub-districts with extremely low spatial performance clustered in the southern suburb and on Chongming Island. By means of Natural Breaks (Jenks) method, the sub-districts of oversupplied and undersupplied UUS development were figured out and then classified into five types to propose corresponding development strategies for future UUS utilization. The evaluation framework and results can give insights for more scientific and rational compilation of UUS master planning, especially for the metropolitan cities with a huge amount of developed UUS.

건축물 안전영향평가와 지하안전영향평가 제도의 합리적 개선방안

Purpose: Architectural structures in modern society ate evolving repeatedly while accommodation the various conditions and demands of society along with the concentration of urban population and rapidly changing economic growth. Architectural design, which along with such economic development, demonstrates the need for al prior safety impact assessment on various risk factors for efficient underground space planning in building planning in accordance with various laws and regulations required by society under the condition of a limited site. Among the safety evaluations for each purpose in accordance with the underground space development, the similarity between the evaluation papers in the ground-related fields of the building safety impact assessment and the underground safety impact assessment is to be studied to study a reasonable improvement plan. Method: Building safety impact assessment and underground safety impact assessment are institutionalized of that the results of the evaluation implementation perpared through the review of the ground safety impact assessment in accordance with the Building Act before and after building permits are reflected in the design documents during licensing and various deliberation. Therefore, each evaluation manual was compared and analyzed to suggest effective linkage of evaluation items, adjustment and sharing of evaluation contents. Result: Through this study, both systems have their respective purposes and differences of impact assessment, and at the same time, it is reviewed that the evaluation and analysis methods included in the target project are very similar of overlapping. A method of exempting evaluations similar to or overlapping with additional adjustments through sharing of related departments was proposed. In addition, additional legal and institutional research is needed to secure the execution power of the two systems in the future.

Underground space use of urban built-up areas in the central city of Nanjing: Insight based on a dynamic population distribution

With the expansion of cities and the emergence of various urban problems, urban underground space has been developed as a solution. In China’s urban transition context, there is a need for the development of underground space in urban built-up areas. In this case-study of the central city of Nanjing, we used spatial analysis and statistical methods to characterize the underground space use of urban built-up areas from a dynamic spatiotemporal perspective. We first analyzed the relationship between the population distribution and the underground space use of the central city of Nanjing based on a Baidu heat map, which can reflect the real-time population distribution, and then, we explored the spatiotemporal characteristics and spatial structure of the underground space use in urban built-up areas. The analysis results provide a reference for planning to improve and optimize the layout of underground space in the central city of Nanjing and, more generally, for the stock-type planning of underground space in urban built-up areas.

Evaluation of urban underground space resources in a delta coastal city

In the multi-aquifer and multi-aquitard system of a delta coastal city, urban underground space is filled with soil, sediment, and rock mass, as well as groundwater. Underground space can be created by excavating the layered strata. Urban underground space includes man-made structures, such as piles, underground structures, subway tunnels, etc. It is important to know how to evaluate the number of underground space resources. With Shanghai as background and the Zhongshan park urban plan unit as an example, a three-dimensional geological model for all sediment layers was established based on the geotechnical investigation. The number of existing underground structures was estimated using collected data. An underground space estimation method is introduced. The proportion of different layers was calculated using a geological model that corresponded to the shallow-middle-deep urban underground space conceptual plan, which can be referred to by underground space planning.

Measuring the monetary value of environmental externalities derived from urban underground facilities: Towards a better understanding of sustainable underground spaces

The development of underground spaces has been regarded as a major contributor to urban environmental sustainability. However, insufficient attention has been paid to the environmental externalities of urban underground facilities (UUFs) due to the lack of a bespoke tool for the identification and monetary valuation of such externalities, resulting in the irrational use of underground spaces. To this end, this study systematically explores the categories of environmental externalities tailored to UUFs, considering both environmental contributions and losses. Furthermore, the framework of the replacement/restoration cost method (RCM) was employed to measure the environmental externalities of UUFs in monetary terms, and the framework was then applied to a series of representative UUFs in China as a case study. The results indicate that the monetary value of the environmental externalities derived from UUFs is non-negligible compared to its construction cost, and the positive externalities dramatically outweigh the negative ones. In addition, there are apparent differences in the constituents of externalities among different types of UUFs. It is found that the effects of energy conservation, air pollution and noise pollution prevention proved to be the main contributions of UUFs to sustainability. This study aims to provide a useful model for the identification and measurement of the environmental externalities derived from UUFs, thus aiding in the decision support of underground space planning, as well as obtaining a sound understanding of the role of underground spaces in sustainable development.

3D spatiotemporal risk assessment analysis of the tunnelling-induced settlement in an urban area using analytical hierarchy process and BIM

ABSTRACT Issues associated with tunnel construction and adjacent building damage risk are becoming increasingly important as cities expand and make more use of their underground space. A typical geotechnical engineering problem is how to determine the ground settlement susceptibility of buildings due to tunnelling excavations. A risk assessment, considering the analysis of several factors, is required for sustainable and resilient planning of urban areas and underground space. The Analytical Hierarchy Process (AHP) has been widely adopted for similar objectives, while AutoRegressive eXogenous modelling (ARX) as the dynamic component has the potential to produce the necessary analysis to underpin the assessment. Additionally, the database and visualisation capabilities of the Building Information Modelling (BIM) framework could provide a promising environment for accommodating such a risk assessment. The proposed methodology reported herein has employed a spatiotemporal analysis using AHP and ARX to produce analytical outcomes that involved several settlement-inducing criteria with respect to their severity and time-dependent groundwater table level changes, respectively. The integration of these analyses within the BIM framework has produced a tool that can define in detail the settlement vulnerability and building-damage assessments within a 3D geology-tunnel-buildings model.

Planning and application of underground logistics systems in new cities and districts in China

Underground logistics systems (ULSs) has been an important topic and research hotspot for urban underground space use in China, especially for implementation in new cities and districts, as it is a necessary element to be considered for city underground space planning. Since these newly planned areas will face many challenges, including increasing logistics volume, spatial constraints etc. if we use the existing freight transport modes similar to old cities. Furthermore, the rapid developments of Chinese new cities provides an opportunity to implement innovative ULS freight transport systems and technology that are efficient and sustainable. Recently, ULS has been included officially in the planning and study for Beijing’s Sub-Center, the Yangtze River Demonstration District and other new cities and districts. However, the real value of ULS will not materialize unless it is successfully implemented. This paper presents the exploration, observations and findings of a few proposed ULS planning and research works in the new districts mentioned. The suitability of goods and freight types in ULS, logistic flow demand forecasting and ULS network systems integrated with underground metro or infrastructure are discussed. Both dedicated and integrated ULS network systems are also compared and analyzed. Despite the many advantages, many challenges and difficulties remain in the planning integration, technology adaptation and implementation of ULSs in new districts and cities, thus, interdisciplinary collaborations is one of the key success factors to ensure ULS can be brought to fruition.

The main characteristics of urban underground space regulatory plan from the perspective of China’s spatial planning: A practice in Beijing Sub-Center

In order to better solve the new problems encountered in the national development, China is gradually establishing a new national territory spatial planning system. It can implement the requirements of whole-area and multi-element control of land and space. Underground space planning is a special planning in the new spatial planning system. We will explore how to scientifically and reasonably prepare underground space planning. Combined with the planning practice of Beijing and Sub-Center, we propose that the underground space planning system should be further improved, especially at the regulatory planning level. It can not only refine the master planning requirements of underground space, but also effectively guide the detailed planning and project construction of underground space. This paper attempts to put forward the main characteristics of underground space regulatory planning, hoping to provide reference for other cities’ underground space planning. The first is ecological priority and limited utilization. Detailed geological survey is the basis of underground space planning. In the Sub-Center, we evaluated the requirements of geological ecological protection and the impact of geological disasters, and delineated the three-dimensional utilization boundary of underground space and the influence scope of geological disasters. The second is the improvement of space management and space vitality. We explore the allocation method of underground space covered area, and divide the covered area into each construction site, giving priority to the key areas such as Universal Studios and metro station areas. The third is multi-dimensional utilization and planning integration. The underground facilities are planned in depth and intensively. The plan puts forward detailed in-depth layout guidance, focusing on the construction of Facility Service Ring, and coordinating the intensive construction of underground tunnels, metro and underground municipal facilities. The fourth is to encourage the application of new technologies. The planning will reserve sufficient space for future development, such as the construction of underground logistics, multistage rainwater collection and underground heat utilization in the Sub-Center.

Study on Implementation Strategies of Multifunctional Linear Underground Space: A Case Study in Beijing’s sub-center

DEVELOPMENT CONTROL PLAN FOR THE SUB-CENTER OF BEIJING (2016-2035) says, a facility service ring with complex functions, balanced layout and integrated above ground and underground space will be constructed, which is efficient integrated underground infrastructure, with a total length of about 36.5 kilometers, coordinating the construction of circular underground systems such as subway, utility tunnel, urban underground logistics, and automatic garbage collection and transfer, and jointly building municipal facilities such as hidden municipal facilities, multi-level rainwater control and utilization facilities, emergency evacuation facilities, underground peak-storage and peak-regulation facilities. Aiming at the feasibility of the project, though analyzing in detail the present situation and planning of land use, pipeline and underground space along the ring and surrounding areas, and fully sorting out the functions and space demand characteristics of the major systems in the facility service ring, deeply explore the advanced technologies such as urban underground logistics and automatic garbage collection and transfer, and propose the inclusive and multifunctional underground space implementation strategies, for the meticulous use of underground space.