Vertical Uplift Capacity of Equally Spaced Horizontal Strip Anchors in Sand

摘要

The vertical uplift capacity of an infinite numbers of rigid strip plate anchors placed in a group and embedded in sand, has been determined. An upper bound theorem of limit analysis in combination with finite elements and linear programming has been used to perform the analysis. All the anchors are loaded to failure simultaneously with the same magnitudes of the failure loads. For different clear spacing (S) between the anchors, the magnitude of the efficiency factor (ξ_γ) is determined; where ξ_γ is the ratio of the failure load for an interfering strip anchor, for given width (B) and depth (d), to that of an isolated strip anchor having the same width and depth. The magnitude of ξ_γ has been found to reduce substantially with a decrease in the spacing between the anchors. It was noted that a rigid soil wedge just above the anchor plate and bounded by planar rupture surfaces separates out and it moves with the velocity same as that of the anchor plate itself. The results available from the analysis were found to compare reasonably well with the available theoretical and experimental data from the literature.