关键词: 锚杆静压桩, 附加沉降, 持荷封桩

Abstract: The settlement induced by the anchor jacked pile reinforcing the existing building foundations is divided into immediate settlement and settlement after construction. The immediate settlement is induced by the lateral deformation and the strength reduction of the surrounding soft soils. Results of the finite element analysis show that the foundation heave or settlement change caused by the lateral soil squeezing is related to the upper load and the properties of foundation soil within 15m below the ground, the worse the soil property, the larger the settlement, that is, the major factor of the settlement in most of the reinforcing projects. At the same time, the project case history shows that, there is a hard soil layer under the foundation, which may be heaved due to soil squeezing around the pile. The worse the soil property is, the larger the influence range of immediate settlement is, the lower the strength of soil mass and the force bearing area are, thus increasing the settlement. According to the measured settlement data of typical buildings, the building the immediate settlement consists of 80% of the total settlement. Combined with the characteristics of the anchor jacked pile construction, the post construction settlement cannot be ignored. Based on immediate settlement characteristics, the “suspended loadingcontrollock up loading” procedure is proposed to minimize the settlements of buildings.

Key words: Anchor Jacked Pile, Immediate Settlement, Lock Up Loaded Piles