Study On The Prediction Of Land Subsidence In Cangzhou Area

Land subsidence is defined as natural or man-made factors affecting the ground under the conditions of emergence of the phenomenon of lower elevation. As natural disasters, the occurrence of land subsidence is a certain geological reasons. However, with the human social and economic development, population expansion, land subsidence phenomenon more and more frequently, increasing the settlement area. Man-made factors on the occurrence and development of land subsidence has been much higher than the contribution of natural factors, in densely populated cities, land subsidence is a kind of particularly serious geological hazards.The economically developed coastal plain areas of east China, densely populated, the demand on water resources, long-term exploitation of groundwater in the region has resulted in large-scale land subsidence. Cangzhou is located in the North China Plain, North China Plain, including Beijing, Tianjin, Hebei and Shandong north-west plains, with a total area of nearly 140,000 km2, land subsidence in China's largest distribution of lace areas, among the most outstanding performance in Cangzhou region. A direct result of land subsidence in Cangzhou coastal plain areas of low ground elevation loss, resulting in sinking of the railway roadbed, storm surge disasters. In analyzing the mechanism of land subsidence in Cangzhou region on the basis of finishing in the region through the years of monitoring data related to land subsidence and prediction to make forecasts for the North China Plain area of land subsidence prediction and forecasting typical work. In this paper, by analyzing the 1995 to 2005 monitoring data related to the study area to determine the hydro-geological parameters, the use of PMWIN (Modflow) the establishment of three-dimensional groundwater flow and the formation of ground subsidence compression coupled model forecast and predicted using this model to study the three mining program area of flow field and changes in the trend of land subsidence.â‘ Mining in 1995 to maintain the level forecast in 2020 under the conditions of the head and changes in the settlement. 2020 forecast the cumulative amount of land subsidence generally greater than 600mm, the largest urban settlement center in Cangzhou, the cumulative value of the settlement up to 3-4m.â‘¡In the South-North Water Diversion and other water projects to achieve the use of water resources under the conditions of mode selection program, intensity of groundwater exploitation has been reduced more than in 1995, the accumulated land subsidence in 2020 to predict the amount, the largest amount of land subsidence within 4m, Cangzhou Most of the accumulated sedimentation 1-2m.â‘¢Circumstances in the absence of South-North Water Diversion mining program to achieve the best forecast results show that, Cangzhou city, Renqiu Hejian to a relatively large settlement with the development of half of the study area the cumulative amount of land subsidence is greater than 1m, Cangzhou Settlement Center can achieve more than 4m.Finally, by analyzing the different mining conditions, the development trend of land subsidence, the optimization program of groundwater exploitation and land subsidence in Cangzhou the prevention and control measures put forward a scientific proposal.