Introduction

The size of an anchor is generally referred to by its weight in air. Anchor holding power is determined by the anchors efficiency multiplied by the weight of the anchor. Anchor efficiency is determined by design, testing and the type of soils which the anchor will be expected to perform in. The efficiency of an anchor decreases as the size of the anchor is increased. A concrete sinker has an efficiency of approximately 0.5:1 whereas modern specialist anchors can have efficiencies up to 100:1 depending on soil conditions.