Consolidation effects on monotonic and cyclic capacity of plate anchors in sand. Issue 8 (20th August 2020)

• Record Type: Journal Article
• Authors: Chow, Shiao Huey; Diambra, Andrea; O'Loughlin, Conleth D.; Gaudin, Christophe; Randolph, Mark F.
• Is Part Of: Géotechnique. Volume 70:Issue 8(2020)
• Page Start: 720
• Page End: 731
• Publication Date: 2020-08-20
• Subjects: anchors & anchorages -- centrifuge modelling -- offshore engineering -- sands; Soil mechanics -- Periodicals; Engineering geology -- Periodicals; Geotechnical engineering -- Periodicals; 624.151
• DOI: 10.1680/jgeot.19.TI.017
• Languages: English
• ISSNs: 0016-8505

Abstract

Abstract : This study investigated the change in monotonic and cyclic capacity of a plate anchor across different degrees of consolidation in dense sand. To quantify the effect of consolidation on anchor capacity, a framework is introduced and validated using centrifuge model anchor test data. The centrifuge tests considered a rectangular plate loaded at varying rates in dense sand, under both monotonic and irregular cyclic conditions, at a fixed embedment depth and with a horizontal load inclination (at the seabed). In order to vary from drained to undrained conditions, the sand was saturated using both water and a viscous pore fluid with viscosity approximately 700 times higher than water. The anchor's ultimate monotonic capacity in dense sand increased by up to 173% as the consolidation response evolved from drained to undrained with generation of dilation-induced suction. This increase in capacity across the consolidation regime can be adequately quantified using the proposed framework; however, uncertainty arises in achieving the theoretical undrained capacity. Both drained and undrained irregular cyclic loading resulted in anchor capacity increases of up to 33%, attributed to soil volume changes associated with cyclic densification under drained cyclic loading and excess pore pressure dissipation under undrained cyclic loading.