城市地面“下沉”的原因新解及其治理方法

Explanation for and Treatment of Urban Ground Subsidence

过量抽取地下水并非造成地沉的主因,应对密集的高楼大厦的荷载压力方向加以甄别.对地沉原因的新解是,地面荷载压力和地层支撑应力较劲的结果,从而导出荷应平衡理论.分析摩擦地桩荷载压力传递机理,发现地层具有整体的支撑应力,提出认识这种无形应力是有价值的自然资源.进而研究它受压的因应规律,可利用它在城市地质片区的整体中进行调济和配置,在防治地沉中发挥中心作用,并可从中获得较大的资源效益.治理地沉的方向应在于增强地层支撑应力,应用沙桩可直接和间接增强软弱地质的支撑应力,力求使它能够和地面不断增荷加载的压力取得并保持平衡状态,就有可能保持地面永不"下沉".

Excessive extraction of groundwater is not the main cause for ground subsidence. The direction of the load pressure of dense high-rises must be taken into consideration. In this paper,a new explanation for the cause is proposed ground load and the ground support, which leads to load-support balance theory. Through the analysis of friction pile load pressure transfer mechanism, it is found that the ground has overall support stress,which is a valuable natural resourece. Applied in geological adjustment, the support stress can play a central role in the prevention of ground subsidence in the urban area. To prevent subsidence,it is necessary to increase the support stress of the ground, which can be achived by using sand pile. The sand pile must maintain a balanced state between the ground and the increased pressure, and thus it is possible to prevent subsidence.