关键词: 地面沉降, 地下水开采, 影响因素, 城市化

Abstract: Since 1990s, land subsidence accelerated again although net withdrawal volume of groundwater did not increase in urban center of Shanghai. Net withdrawal volume of groundwater in urban center, however, is not the crucial factor controlling the land subsidence. At the same time, more and more infrastructures, such as high and super-high rise buildings, deep building foundations, underground structures, subway tunnels, underground path structures, were constructed in the multi-aquifer-aquitard system (MAAS) in Shanghai. Land subsidence in Shanghai is correlated with activities of urban construction according to correlation anaylsis of land subsidence and urban construction. Investigation on urban construction induced land subsidence is now receiving a great concern. However, mechanism of how urban construction affects the acceleration of land subsidence in Shanghai has not been well addressed. This study was undertaken to evaluate the influential factors on the development of land subsidence with the process of urbanization in Shanghai. The influential factors include additional load consisting of static load and dynamic load during and after structures construction, underground structures construction involving foundation engineering and construction of tunnel, drawdown of groundwater level due to leakage of underground structures, decrease of recharged volume of groundwater from surroundings, and cut-off or partially cut-off effect of underground structures in aquifers.

Key words: land subsidence, groundwater withdrawal, influential factors, urbanization