中国沿海地区地面沉降问题思考

Reflection on ground subsidence of coastal areas in China

中国沿海地区地面沉降主要发生在大河三角洲及沿海平原区。文章主要以我国两大沿海城市———上海及天津为例,分析和阐述了沿海地区发生地面沉降的机理以及影响地面沉降发生发展的诸多因素。指出,孔隙水承压含水层中抽取地下水将引起承压水位降低进而引起土颗粒承担的有效压力的增大,从而使土层压缩。影响沿海地区地面沉降的因素有新构造运动、全球海平面上升、软土地基自然沉降、过量抽取地下流体以及建筑施工造成的局部沉降等。文章认为,在诸多影响因素中,人类过量开采地下流体是导致地面沉降发生的主要原因,人类应在资源利用和环境保护方面力争双赢。

The ground subsidence of the coastal area in China mainly occurs in the regions of big river deltas and coastal plains. Based on the cases of Shanghai and Tianjin, this paper analyzes the genetic mechanism of ground subsidence in these areas and what causes is. Pumping groundwater from pore water confined aquifer can lower the confined water level and increase the effective stress beared by soil grains. The results of these processes are that the soil layers are compressed. The factors which affect ground subsidence are as follows: neotectonic movement, global sea level rising, natural soft soil foundation subsidence, excess underground liquid pumping, local subsidence resulting from building operation, etc., Among these factors, excess underground liquid pumping by human is the primary factor that induced ground subsidence. It is important that keep the balance between resource utilization and environmental protection.