|
Abstract As the present main design method of excavation engineering，the bar-load-spring model，naturally induces several problems which need to be solved. A unified calculation method of the pressure on the supporting structure considering the soil-water interaction is presented，which is more reasonable in the load calculation. Since safety factors system based on the bar-load-spring theory may not be enough to incorporate all the failure modes of foundation pits，new safety factors controlling stability of foundation pits and existing safety factor modified to reflect the size effect should be recommended. Current excavation design method took the influence of safety factor on deformation into account，which was different from the idea of traditional safety factors. Two bar system FEMs such as the bar-load-spring model of circular pits and double stiffness model of soil spring at the passive zone are proposed，which can consider size effect of circular pits and space effect of soil excavation divided into block in strip foundation. Some future research directions on excavation are pointed out.
|
|
Received: 19 May 2013
|
|
|
|
2013, Vol. 32 
