The Mechanism Of Land Subsidence And Its Countermeasures For Prevention In Tianjin Urban City

Land subsidence is very popular all over the world,especially in urban areas.Land subsidence in Tianjin urban area has become increasingly prominent,seriously affected the urban planning and construction,and the local people's living environment,and caused huge economic loss,with the integration of the beijing-tianjin-hebei region and the construction& development of urban construction.Based on a lot of relevant papers and data at home and abroad on land subsidence,combining with the deep quaternary cover in Tianjin,shallow underground water level and widely distributing soft soil,This paper expounds the formation and development process of land subsidence in Tianjin comprehensively,systematically analyzes the influence factors of land subsidence and set up a mathematical model of land subsidence for prediction,based on this,puts forward control measures and suggestions of land subsidence specifically.From the research of the new development trend of ground settlement in urban area of tanjin in recent years,this paper detailed analysis the influence factors of ground subsidence,such as the new tectonic movement,the consolidation deformation of quaternary strata,sea level rise,ground water exploitation and city high-rise building,and study the mechanism of land subsidence in Tianjin.The grey GM(1,4)model of land subsidence in Tianjin urban area is set up based on land subsidence monitoring data and the characteristic of the urban land subsidence in tianjin,three important factors are adopted,such as groundwater exploitation,tectonic regional subsidence and loose strata consolidation.Land subsidence rates in 2020,2025 and 2030 are forecasted and predicted that land subsidence rate is gradually warming trend in central urban area of tianjin,sedimentation rate in 2020 is 13.39 mm,9.36 mm in 2025 and 6.12 mm in 2030,on this basis,we propose the combination of technical management and administrative management methods for the prevention and control of ground settlement countermeasure,depending on the concept of scientific& sustainable development.On the points of prevention and control measures,it puts forward open sourcethrottling,adjust the distribution of ground water exploitation,strengthen management on the exploitation of deep groundwater and usage of freshwater as oilfield injection water.It's very important to the development,planning and construction for the city of Tianjin,on the one hand,it provides scientific basis for control measures on ground subsidence's disaster prevention with rapid economic development of Tianjin.On the other hand,it's helpful to reasonable exploitation and utilization of underground water resources,and.to provide technical support to protect the people living environment.And it has important reference value to forecast the early warning system for land subsidence research and promote sustainable economic and social development in tianjin.