基于情景分析的天津市滨海新区地面沉降预测

鉴于地面沉降演化的地质系统渐变性特征,从主要致灾因子考虑建立地面沉降数值模型。设计3种地下水开采情景,编译计算机程序预测地下水位动态变化过程中的地面沉降值。至2020年,在最不利、适中和最理想3种情景下天津市滨海新区最大累计沉降量分别达640 mm、520 mm和150mm;全区平均累计沉降量分别达268 mm、177 mm和95 mm。

LAND SUBSIDENCE PREDICTION IN BINHAI NEW AREA OF TIANJIN BASED ON SCENARIO ANALYSIS

Land subsidence is a kind of slow-onset geohazards and accumulated for over years.In terms of the main factors which potentially caused land subsidence,the numerical model of land subsidence was established.With three groundwater extraction scenarios,the computer program was compiled to predict the land subsidence in the process of dynamic changes of groundwater level.Maintaining the same condition of groundwater exploitation in 2007（Scenario 1）,from 2007 to 2020,the maximum accumulative subsidence in Binhai New Area of Tianjin（TBNA） will be 640 mm and the average accumulative subsidence will be 268 mm.With 2% decreases in groundwater exploitation year by year（Scenario 2）,the maximum accumulative subsidence will be 520mm and the average accumulative subsidence will be 177mm.With the water from South-to-North Water Transfer Project replacing groundwater exploitation completely（Scenario 3）,the maximum accumulative subsidence will be 150 mm and the average accumulative subsidence will be 95 mm.