Pullout capacity of irregular shape anchor in sand

Abstract

This paper presents research done on a special type of irregular shape anchor and its pullout capacity. Many experiments and theoretical studies have been done on the pullout capacity of anchors. However the irregular shape anchor is an exception. A normal anchor system needs grout and excavation for installation, but installation of the irregular shape anchor involves driving the anchor into the soil and pulling it out to increase the soil compression through rotation of the anchor head. The irregular shape of the anchor presented is a new anchor system, which is a state of the art product in plate anchor design that does not need any grouting or excavation on site. According to studies, the maximum resistance of the anchor increases depending on the embedment ratio and sand compaction, which may be loose or dense sand. The experiments for this irregular shape anchor model with a length of 297mm were conducted in a chamber box and the embedment ratio L/D used in this experiment varies between 1 and 4. The weight densities of the dry sand used for loose and dense. The results obtained show that the embedment ratio and sand weight density have significant effect on the pullout capacity of the anchor. The pullout capacity increases with increment of the embedment ratio and sand weight density. Evaluation using the dimensionless breakout factor also shows that the value increases with incrementing embedment and sand weight density.