Breakout capacity of model suction anchors in soil

Abstract

The breakout capacity of eight model underwater suction anchors was investigated in a 30-in. (76-cm) wide, 72-in. (183-cm) long, and 32-in. (81-cm) deep unpressurized cast iron tank. The test soils were a medium fine sand, a silt, and a clay. A pullout rate of approximately 0.1 in./min (0.3 cm/min) was used for all tests.A breakout capacity equation for the suction anchor was developed based upon the Mohr–Coulomb failure theory. Predicted breakout capacities compare favorably with the measured values from the laboratory model study. The breakout capacity equation which is developed is therefore satisfactory for the range of conditions studied.The suction anchor possesses a high degree of mobility and would be particularly useful for short-term anchorage. Potential applications of the suction anchor include the anchorage for research submersibles, coring platforms, and certain salvage and dredging operations.