Experimental Observations of Plate Anchor Keying Process in Transparent Soil: Performance of Different Keying Flap Designs

Plate anchors are increasingly employed in offshore engineering due to their effectiveness in providing reliable holding capacity. However, observing and directly visualizing the keying process, crucial for understanding the mobilization of anchor capacity, has been challenging due to the opacity of natural soils. This study presents experimental observations of plate anchor keying processes utilizing a transparent soil technique, overcoming traditional observational limitations. Through direct visual analysis, the performance of anchors equipped with different keying flap designs, including plain plate anchor without flap, anchors with outward- and inward- rotating flaps, was compared. Results demonstrate that different flap designs significantly affect anchor behavior during keying, influencing activation timing, vertical bearing area, embedment loss, and anchor capacity. The transparent soil approach provided insights into anchor-soil interaction mechanisms and offered robust experimental validation of previously published numerical analyses. These findings are expected to contribute valuable guidance for optimizing anchor designs in offshore engineering with enhancement of understanding of plate anchor keying mechanism.