Generalized Design Approach for Inclined Strip Anchors in Clay
Publication: International Journal of Geomechanics
Volume 17, Issue 6
Abstract
The estimation of the undrained pullout capacity of plate anchors is vital for the design of offshore floating facilities and has been an active topic of research for several years. Most of the previous studies have proposed empirical relationships to predict the undrained pullout capacities of inclined anchors. Generally, the buoyancy effect is added to the shearing resistance to obtain the total capacity, which is less than or equal to the maximum capacity. In this paper, an alternative mechanism-based simple design methodology is proposed to estimate the undrained pullout capacity of inclined anchors. A series of finite-element analyses are performed for a range of anchor inclinations in soils with uniform and heterogeneous shear strength. The effects of anchor embedment, soil unit weight, and anchor–soil interface tensile capacity are studied in a systematic manner. A relationship has been developed to estimate the depth at which the anchor undergoes a transition in the failure mechanism from shallow to deep failure mode. Robustness of the proposed methodology is also examined for a generalized shear strength profile of the soil. The proposed model estimates pullout capacity with the maximum error being less than 5% for any soil or anchor property.
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© 2016 American Society of Civil Engineers.
History
Received: May 18, 2016
Accepted: Sep 21, 2016
Published online: Nov 18, 2016
Discussion open until: Apr 18, 2017
Published in print: Jun 1, 2017
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