Impact On Land Subsidence In Beijing Building Load

Urban ground subsidence is influenced by human factors and natural factors. Ground subsidence is geological disasters caused by stratigraphic vertical compression. This kind of geological hazard is irreversible, widespread and difficult to control. With the rapid development of urban construction, groundwater sustained overexploitation and urban construction load increasing significantly, ground in Beijing is further development on the original basis, causing a decrease in urban flood-carrying capacity, safety risks in underground pipelines, gas pipelines underground buildings and high-rise buildings. Consequently, research of the impact of urban building load on ground subsidence has important value to rational city planning and urban ground subsidence prevention and control.High resolution remote sensing technology in study of regional land subsidence monitoring and city building detection has achieved positive progress. Research about the relationship between regional land subsidence and building load is also relatively few at present. The settlement mechanism of urban regional land subsidence is complicated due to complex subsurface environment and various influential factors.This paper has an analysis of spatial distribution of urban ground subsidence and urban building load, using spatial data management, spatial analysis and visualization in Geographic Information System (GIS). This paper also analyzes the relationship between the two with the help of scale factor. This paper provides a basis for deeply understanding of the settlement mechanism of urban regional land subsidence and provides reference for city construction.This paper centers around the effect of urban building load on urban ground subsidence.,and carries out the following three aspects.1. Beijing land subsidence monitoring based on TerraSAR-X images and Permanent Scatterers Interferometry technique (PS-DInSAR). This paper uses twenty-two TerraSAR-X imagery and PS-DInSAR technique to obtain the rate of land subsidence at PS points. After the post-processing by GIS tools, this paper acquires the spatial distribution of the partial surface subsidence during the3years from2010to2012in Tongzhou District of Beijing.2. Using high-resolution image GeoEye-1as data source, extracting building roof outline using vectorization, extracting building shade outline using an object oriented classification technique, estimating the building load by shadow method, and obtaining the spatial distribution of urban building load.3. Applying multi-level grid, analyzing the correlation between the ground subsidence phenomenon and the urban building load in different scale. Conclusion:ground subsidence phenomenon is related with urban building load, the greater urban building load is, the more serious ground subsidence phenomenon is.