The Application Research Of Surface Deformation Monitoring And Urban Expansion Based On 3S Technology In Tangshan City, Hebei Province

The ground deformation is the surface vertical deformation phenomenon caused by natural factors and human factors.In our country,the surface deformation phenomenon of different degree have taken place in many cities and regions.With the rapid development of urban construction,the ground deformation hazards are becoming increasingly important,and it has the characteristics of wide distribution and changing process difficult to detect.Most of the northern cities ,many coastal cities and regions are all facing the problem of ground deformation,which directly influences the regional environment and the sustainable development of social economy,and threatens people's safety of life and property . Consequently,it is important to monitor accurately land subsidence and its development.Based on radar remote sensing and optical remote sensing technology,this dissertation takes Tangshan City in Hebei Province as the study area, and using the multi-sensor and multi-temporal remote sensing data ,studies the methods and techniques of the subsidence information extraction in coal mining collapse area.In this process,making full use of the existing data ,information and priori knowledge in this field ,etc.of the study area,and combining the respective characteristics and advantages of radar remote sensing and optical remote sensing,the longer-period ground deformation data of the study area is extracted ,including change area,change speed and change quantity,etc.as well as analyzes the occurrence cause of ground deformation hazards and its influences on urban expansion.It has preliminarily formed a set of effective method combination and work flow suitable to ground deformation remote sensing information extraction of the mining cities,and achieves the goal of the macroscopic,fast and accurate monitoring of the urban expansion and hazards caused by ground deformation in mining cities by remote sensing tenology,then provides decision basis for the relevant functional departments.The maincreative contributions and research results of this dissertation are listed as follows:1.Combining radar remote sensing with optical remote sensing, high precision land subsidence vertical information is extracted by radar remote sensing technology,and the spatial distribution of subsidence regions is extracted indirectly by combining optical remote sensing technology with hydrops phenomenon,each taking its director, and achieving the mutual complementation as well as the mutual verification.This method provides a scientific,reasonable and effective way for studying ground deformation of mining cities,land subsidence prediction and trend analysis of the mining regions, also having feasibility and maneuverability.2.Based on ASTER multi-band remote sensing data, analyzing in detail spectral characteristics of ground objects located in subsidence regions,and aiming at the fact that different objects have the same spectrum,the method of normalized difference water index based on ASTER data is presented,namely NDWIASTER1,4=(ASTER1 - w×ASTER4)/(ASTER1 + w×ASTER4). The method is obtained from the improvement and development of the previous research, The application and verification of this method shows good effect.This method not only solves the problems of terrain classification in study area,but also provides the powerful reference for applying the remote sensing technology into the ground surface deformation monitoring in urban areas.3.First time integrating the research data and information into the Digital Earth Platform(DEP) by format conversion and projection transformation,and taking functional advantage of DEP,such as the three-dimensional display, interactive operation on layer,etc.the combination of the mining area distribution, hydrops distribution and subsidence area distribution is analyzed and verified,then improving the analysis efficiency and accuracy.4.It is systematically expounded that the three types of ground deformation,the reasons of subsidence caused by the coal mining which has the maximum hazard degree,three models of subsidence,and influencing factors of subsidence.On the basis,analyzing how subsidence causes hydrops,then the feasible conclusion of monitoring coal-mining subsidence by hydrops is drawed5.The dissertation carries out research on the application of remote sensing technology in monitoring ground subsidence of coal-mining collapse area,analyzing and discussing in detail the core technology related to radar remote sensing and optical remote sensing, and the whole application technique system.It maks deep discussion on remote sensing information extraction technology of cities distribution and coal mining subsidence concentration area,and maks systematic analysis and evaluation for the accuracy and precision of the information extracted.6.Based on the technology studied of this dissertation,six phases hydrops information in study area is extracted by TM,ETM,ASTER multi-source and multi-temporal remote sensing data,combining with the mining area distribution of Kailuan Coal Mine.Meanwhile,data overlay and statistical analysis are made by GIS technology,producing the hydrops change maps of ten mining areas of Kailuan Coal Mine,which included the area,region and speed of hydrops dynamic change of the ten mining areas.In terms of hydrops change information,the subsidence status of ten collapse mining areas of Kailuan Coal Mine is analyzed.7.Around the urban expansion information extraction, the dissertation adopts the multi-source and multi-temporal optical remote sensing data. Making use of methods and technologies named band combination,image enhancement,data fusion and terrain classification,etc.the outline drawing during different periods in Tangshan is extracted.On the basis of the comprehensive analysis on the expansion area,rate and direction of Tangshan City,it analyzes the influence which is caused by coal-mining subsidence on Tangshan city expansion.Founding that Jing Ge Zhuang located in the north-east of Tangshan City will hinder the development along the north-east direction of Tangshan City in the near future, the reasonable conclusion which shows Tangshan ought to develop towards the west and north-west direction is drawed.8.Based on the radar remote sensing interferometry technology,making full use of the above research results and information related to the region,the subsidence quantity change information of the five time segments during the decade is extracted.On foundation of the effective validation and result data analysis,it discusses influencing factors of subsidence change.Since Tangshan City was listed in the comprehensive treatment demonstration zone of the national coal-mining subsidence region in 1999,underground coal mining is totally banned in Tangshan urban area.The radar satellite monitoring results shows the velocity of subsidence is becoming slower,and the area of subsidence is becomig smaller,which is consistent with the conclusion drawed by the related departments that is the ground subsidence of Tangshan City has been controlled effectively.