Analysis Of Land Subsidence Of Negative Landform Region In Tianjin Binhai New Area

Land subsidence is one of the geologic hazard in world wide range, that it alwaysoccurred on the coastal areas in China, influencing social and economic developmentof Tianjin. Land Subsidence in Binhai New Area had a long history, wide distribution,a grand total amount, resulting in many kinds of disasters, large loss, long lasting,difficult to control, especially thenegative landform which threat to coastal new areadevelopment and opening up of the influencing factors.Generalized negative landform is topographic feature which lower than the adjacentarea or neotectonics subsidence areas. Negative landform in Binhai New Area refersto the special landform formation caused by natural and artificial factors. Negativelandform has background negative landform and local negative landform. Backgroundnegative landform means natural factors lead to the formation which the middle partlower than the west and east during sea changing process. It also be called" therelative negative terrain" because its elevation lower than the adjacent area; localnegative landform due to artificial factors within individual distribution, its elevationbelow the sea level of the low altitude, it can also be regarded as negative landform inthe negative landform, so it could be called" absolute negative terrain". These twokinds of negative landform in Binhai New District related to land subsidence closely,of which human factors affected the most prominent.This paper says the local negative landform below sea level under the influence ofartificial factors, as a result of long-term land subsidence. This paper analysis thelocal negative landform current situation, development trends, causes and harm.Through the analysis of land subsidence history in Binhai New Area, current situationand trend of development, negative evolutioncharacteristics of landform geographical,and influence on the development of land subsidence. The author use RTKtechnology to monitor and predict the negative landform developing trend. The authoranalyzed the cause of negative landform from three aspects, the tectonic subsidence,soft soilconsolidation, and groundwater mining. The author analyzed the maindisasters caused by negative landform in flood control, storm surge resisting, highspeed railway operation and other aspects.