Vertical deformation or settlement of foundation soil caused by compression under the action of building load.
Uniform settlement is generally less harmful to buildings, but when it is too large, it will also reduce the elevation of buildings and affect their use; Uneven settlement is harmful to buildings, which will cause additional stress and cracks in buildings, and even local components will break, endangering the safety of buildings.
Over-exploitation of groundwater, exploitation of solid minerals, exploitation of oil (natural gas), extraction of brine, heavy pressure of high-rise buildings, influence of continuous low load and underground construction may all cause ground subsidence.