چكيده به لاتين
In last decades numerous researches have been done on plate anchors as light structural members that can be implemented onshore and offshore. In this paper, a new-designed plate anchor named “Opening plate anchor”, increasing its bearing section area during uplift is introduced. In this experimental investigation, the influence of the embedment ratio (depth of embedment/anchor width) of the plate anchor, anchor width (120, 150, 180, 250 mm), soil surface covering and different configurations of anchors with more than one pair of wings on the anchor pullout capacity and anchor displacement during uplift tests is investigated.
Particle Image Velocimetry (PIV) is used to study soil deformation around the anchor at the maximum pullout load’s instant. According to PIV analysis, two failure surfaces are observed and two equations are presented to estimate the ultimate pullout load of the shallow and deep opening plate anchor. Furthermore, the pullout loads predicted by prevalent theoretical methods have been compared with obtained experimental values.
It was observed that the pullout capacity (P_u) was significantly influenced by anchor embedment ratio, but the anchor displacement corresponding to the maximum pullout load (d_u) increased slightly as the embedment ratio increased. As the anchor width (B) increased, P_u and d_u increased, but the breakout factor (dimensionless pullout load) decreased. For shallow anchors, the sand deformation zone lines formed a curve that extended to the soil surface. For deep anchors, the sand deformation zone formed a truncated cone in the soil. Furthermore, increasing number of pairs with vertical space of 1.5B, decrease the anchor efficiency (E) significantly. In order to increase the efficiency of the anchor with more than one pair of wings, the minimum space between pairs is about 3.5of anchor width.
