Effect of excavation of foundation pits on settlement and stability of buildings at top of slopes

A multi-storey building is located at the top of a slope, and the minimum distance between the building and the slope is 5.9 m. The slope adopts double-row piles, but the embedded depth is deficient. Due to the need of construction of residential buildings, the pit excavation is done at the slope toe and obvious subsidence and deformation of building is caused. The monitoring results show that the building appears uneven subsidence, the tilt rate significantly exceeds the allowable values, and the slope has obvious deformation. The deformation and subsidence monitoring results are analyzed and predicted by using the grey theory method. According the forecast results, the supporting measures should be taken for the slope, otherwise sliding failure will happen. So, the pile-anchor retaining wall is taken to support the slope. Since a circular sliding or a fold line sliding is possible, both the circular sliding method and the fold line method are used to analyze the slope stability. The stability of pile-anchor retaining wall is also analyzed to verify the rationality of the supporting measures for the slope.