EVALUATION OF DEFORMATION CAPACITY FOR RC T-SHAPED CANTILEVER WALLS

If RC structural walls are properly designed and proportioned, these walls can behave in a ductile manner. To achieve this goal, the designer should provide adequate strength and deformation capacity of structural walls corresponding to each performance level (e.g. immediate occupancy, life safety and collapse prevention). This study investigates the drift and ductility capacities of T-shaped structural walls on the basis of results from experimental tests and sectional analyses. To determine proper deformation capacities for T-shaped structural walls, structural performances of T-shaped walls were evaluated with several parameters such as longitudinal reinforcement ratio, distribution of longi-tudinal reinforcement, lateral confinement ratio, and axial load ratio. Based on these results, the level of deformation capacity specified in current design provisions (ICBO, UBC 1997), which were expressed as both strain-based damage limit and interstorey drift ratio, were evaluated.     

Factors Affecting Late Twentieth Century Land Use Patterns in Kamakura City,Japan

Land use patterns can be viewed as a reflection of various factors including zoning regulations and environmental and social influences. To understand the effects of these factors, late twentieth century land use data for Kamakura City, Japan were analysed in relation to zoning regulations and geomorphological influences using geographic information systems techniques. Kamakura is a typical example of an Asian historic city experiencing the pressures of recent urbanisation. Statistical analyses, including principal component analysis, were employed to identify factors affecting changes in major land use patterns over time and space. The rapid increase in population and government regulation in the 1970s led to the construction of low-rise buildings in piedmont areas. However, topography and conservation activities limited construction to areas with slope angles below about 10°. In the late 1980s and early 1990s, the area of vacant land on the urban lowlands increased due to the large increases in land value during the Japanese Bubble Economy phase. Land use intensified in most urban areas, although hilly areas were still characterised by low-rise buildings. Although urban sprawl has occurred in many cities in Asia, this has been limited in Kamakura because of strong land use regulation and conservation activities. However, the city has experienced high-rise development in its urban lowlands.