Informationized Construction Monitoring And Numerical Simulation Of Deep Foundation Pit

As Land subsidence commonly prevailing worldwide, especially in those areas whereIndustrialization and Urbanization level are really high, it is now becoming one of the mostimportant environmental geological problems and city geological disasters that could influcedevelopment of economic society. Although with modern economy, dense populatioion andhigh Urbanization level, Hebei plain owes overall low and flat terrain, and serious landsubsidence occurring in it causes great economic losses and damages and deep effects onregional economic development, environmental protection, taffic and flood control, people’slife, and industrial production and urban construction.Characterisitics, mechanism and influenced factors of land subsidence in Hebei plainare systematically analyzed in this thesis according to the forming process and developmentof Hebei plain. Several aspects including the relationship between compressible soil and itsconsolidation status soul structure and clay mineral components of land subsidence centerwith land subsidence, layered-soil mechanics tests, step bench mark monitoring,groundwater monitoring and simulation of groundwater exploitation-land subsidence model,have been studied. Also the motive development of land subsidence from2008~2010inHebei plain has been monitored by application of the InSAR technology.In accordance with the results of above researches as well as with history, nature anddevelopment trend of land subsidence, present exploitation situation of groundwaterresource, thickness of Quaternary formation, ratio of clay minerals in main mining strata,hydrogeological texture and basement structure in Hebei Plain, easily land-subsidece-pronearea are evalued through Analytic hierarchy process to be high, moderate and low landsubsidence-prone areas. On the base of the land-subsidece-prone areas, population density,society economic conditions and prevention capability, land subsidence controlling area inHebei plain are partioned into key, secondary key and common prevention regions.More research breakthroughs and innovations of this Doctoral thesis thanfore-researches include such aspects that structure of strata in Hebei plain are sysmaticalyanalyzed by microtextur, genesis of land subsidence and major facters influecing land subsidence are reseached through soil mechanics tests with a tiered observed result in recentyears. It is concluded that land subsidence exists everywhere the step bench mark boreholehave been drilled in Hebei plain, rates of land subsidence transfer from big to small as thedepth of strata, and the main fators influencing land subsidence in Hebei plain are extractionvolume of groudwater, compressability of strata texture and ratios of clay mineral incompressable soil.