Study On The Characteristics Of Land Subsidence Disaster In Tianjin Harbor Industrial Park

Land subsidence is a slow degeneration of geological disasters. It is imperceptible anddifficult to recover once occurs. Land subsidence is the main geological disasters in Tianjin.The largest cumulative settlement is more than3m as records. Land subsidence will not onlyreduce the elevation in coastal areas, also cause damage to the public facilities and buildings.More serious is settlement will reduce the level of tide embankment, which endanger theefficiency of the dam. It will cause heavy loss on people’s life and property. This topic basedon the special geological condition aims to study on characteristics of settlement in TianjinHarbor Industrial Park through test and monitoring method, then offers some suggestions tocontrol the development of settlement.It shows the first Marine stratum is in owe consolidation and the aquiferⅠ to Ⅳis innormal consolidation though the consolidation experimental research of the Quaternarystrata sampling and drilling in Tianjin Harbor Industrial Park. With the increase of depth, thestate of consolidation is better and better. It also indicate critical water level doesn’t exist inthis area. Once the groundwater is exploited, it will cause the settlement.The monitoring data indicate that the average subsidence rate in Tianjin Harbor IndustrialPark. is30-40mm/year in recent years, and local area is more than40mm/a. The data oflayered benchmark monitoring suggests that the annual settlement of the shallow layer (soillayer and the first marine layer) decreases, but the total amount increasing. Accompanied bya steady decline of the water level in Aquifer IV, the corresponding strata continues tocompress by the effect of groundwater exploitation since2010.The cause of ground settlement in Tianjin Harbor Industrial Park is complex. Of thenatural causes, the annual settlement caused by The tectonic activities is2.0mm/a; causedby the soft soil consolidation is approximately1.0mm/a. Of the human causes, the mainreason of settlement is groundwater exploitation and large-scale reclamation project. Thetotal settlement of above is over60%For the reasons of settlement in Tianjin Harbor Industrial Park, this article offers thesuggestions of control the land subsidence disaster developing in Land reclamation areafrom management and technology aspect.