Pullout capacity of multi-plate horizontal anchors in sand: an experimental study

A horizontal anchor is a structural member designed to resist the vertical pullout forces and ensure the stability of structures like the tower foundations, masts and bridges. This paper focuses on the experimental study for the estimation of the ultimate pullout capacity of multi-plate horizontal anchors embedded in the sand. The tensile load of a structure is resisted by the multi-plate anchors using the many plates connected along the central shaft. The multi-plate anchors would be capable of generating higher pullout capacity in comparison with the single-plate anchors, for an embedment depth considered. The pullout capacity is generative of the inherent structure of the multiple plates encompassing multiple layers of sand. The paper presents a comparison of the multi-plate anchors with the existing studies of single-plate anchors. Results show the multi-plate anchor replacing the existing single-plate anchors efficiently. Few of the primary conclusions are (a) the increase in the pullout capacity of the double-plate and triple-plate anchors with the increase in the embedment ratio, (b) the critical embedment ratio being indicative of a transition of the failure mechanism developing for shallow and deep anchors, (c) a decreasing pullout capacity for shallow multi-plate anchors in comparison with the single-plate anchors, and (d) an increasing pullout capacity for deep multi-plate anchors in comparison with the single-plate anchors. The paper provides a brief discussion on the scale effect, the effect of spacing, the effect of the shape of the anchors on the pullout capacity.