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This study examines the influence of different construction methods on the lateral displacement of diaphragm walls in large-scale, unsupported deep excavations. Using the three-dimensional finite element method (FEM) with PLAXIS 3D 2017 software, the research assesses how varying construction techniques impact wall stability, particularly in proximity to sensitive structures like metro systems. The project uniquely integrates peripheral top-down and central bottom-up approaches to minimize environmental disruption. Key focus areas include the roles of back-pull slabs, zoned excavation, and cross walls in reducing wall deformation. Findings reveal that zoned excavation significantly controls lateral displacement on longer site sides, enhancing adjacent structure safety and overall construction integrity. Back-pull slabs are shown to effectively decrease top wall deformation, thereby increasing structural stiffness. Moreover, despite their considerable length (nearly 60 m), cross walls play a crucial role in controlling lateral deformation along the excavation's length. These insights offer valuable guidance for future projects, especially in regions like Taiwan, where experience with such large-scale, unsupported excavations is limited. [ABSTRACT FROM AUTHOR]

• The distal relationship between Taipei's resource inflows and nonrenewable resource production in Taiwan was investigated. • Cross-scale emergy synthesis revealed the reliance of Taipei's resource inflows on Taiwan. • The demand of construction materials in Taipei's peri-urbanization is the underlying driving force of the development in Taipei's remote areas. Urbanization not only causes environmental changes in metropolitan regions but also influences the ecological and socioeconomic changes of distant land areas due to increasing demands on resource use and waste emissions. Previous studies on the assessment of urban systems have focused on the city or metropolitan areas under study. There is a need to incorporate urban land teleconnections to investigate the relationship between a city and distant land areas during the process of urbanization. This paper analyzes the teleconnection of the energy and material flows associated with Taipei's peri-urbanization and remote areas in Taiwan. The cross-scale emergy synthesis of Taipei and Taiwan was examined first to investigate the relationships of the material and energy flows between Taipei and Taiwan. The exploitation of non-renewable resources in Taiwan during the 1990s was driven mainly by the construction and development taking place in Taipei. Furthermore, compared with Taiwan, the Taipei area relies heavily on external resources. The results of the emergy evaluation of materials flows in Taipei indicated that 85% of the construction materials used were imported from other remote areas during the past 30 years. The use of construction materials in Taipei had a higher intensity in the city center during 1982–1992 and in the peri-urban area during 2002−2014. The results of the emergy synthesis indicated that urban land teleconnections exist between peri-urban areas of Taipei and other distant areas in Taiwan. [ABSTRACT FROM AUTHOR]

The Fifth Assessment Report released by the Intergovernmental Panel on Climate Change (IPCC AR5) revealed that the scale of greenhouse gas (GHG) emissions in Asian cities is similar to those from developed economies, which are driven predominantly by economic growth. Due to variations in geographic and climatic contexts, culture and religion, living style and travel behavior, governance and institutions, and a wide range of density and land use mixes, there are significant variations in urban form patterns across Western and Asian cities. This paper uses a systematic review, which is a critical interpretive synthesis methodology, to review keywords of studies related to urban form among East and Southeast Asian cities. From 3725 records identified through database searching, 213 studies were included in qualitative analysis. The results show that, although the population density in built-up areas is higher, annual population density is declining significantly in East and Southeast Asia. In addition, there are various kinds of land use mixes including horizontal, vertical, and temporal forms. As a whole, the inconsistencies of urban form characteristics exist not only between Western and Asian cities, but also among Asian cities. Serious population density decreases in Asian cities might indicate that they are undergoing similar urban development processes to those of Western cities. We should be aware of the potential lock-in trends of urban development patterns in Chinese and Southeast Asian cities. [ABSTRACT FROM AUTHOR]