Effects of embedding depth and load eccentricity on lateral response of offshore monopiles in dense sand: a centrifuge study

Abstract

Two model piles with outer diameter D = 50 mm are loaded laterally at 100×g in a large-beam geotechnical centrifuge. The normal strains on both the tensile and compressive sides are measured using fibre Bragg gratings. An incremental method is introduced to define the pivot point. The testing and analytical program enables the effect of the embedding depth and load eccentricity to be quantified. The key findings are as follows. 1) The piles generate asymmetric tensile and compressive strains during bending, and the tension-compression asymmetry becomes more pronounced at the pile toe and for shorter piles. 2) The piles transition from flexure to rotation as the embedding depth is decreased from 9D to 3D, where the uniqueness of the ground-level rotation and deflection (θg–yg) relationship disappears. 3) The reaction and deflection (P–y) relationship flattens with increasing embedding depth but seems independent of the load eccentricity.

Dataset for centrifuge modelling of laterally monotonic loaded monopiles in saturated dense sand

“…4 Configuration of the test: (a) pile embedding depths and loading eccentricity; (b) established testing system (reproduced from Figs. 2 & 3 of [1] ).

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“…The load velocity was 0.1 mm/s at the actuator level. The data during loading were saved into a CSV file every 0.05 or 0.02 s. More details about the experimental design, materials and methods are described in [1] .…”

“…File ‘04 Calculated_DeflectionReaction’ presents the calculated data for the normalised pile deflection y/D, pile rotation θ, bending moment M, shear force T and soil reaction P. The methodology and workflow of obtaining this data were described in detail elsewhere [1] . The profiles of y/D, θ, M, T and P can be also plotted, and, similarly, an example is shown in Fig.…”

“…2 Profiles of the pile deflection y/D, rotation angle θ, bending moment M , shear force T and soil reaction P for Test 2 (L/D = 7, L e /D = 10; reproduced from Fig. 7 of [1] ). …”