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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 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]