Wave Flume Simulation Experiment on Influence of Wave Load on Bearing Capacity of Monopile

doi:10.16183/j.cnki.jsjtu.2019.268

Abstract

Abstract:

For the foundation of the monopile in the shallow water environment,a scale model of sand-monopile-wave was adopted in the wave flume simulation experiment, and the static load test of the monopile under wave action was explored. The pore water pressure of the soil around the monopile and the settlement of the monopile at different wave loads were examined. Based on the static load test results, the interaction mechanism between sand and the monopile subjected to wave load, the characteristics of load settlement curve,and the influence of excess pore water pressure (p_s) on the vertical bearing capacity of the monopile with various pile diameters were analyzed. The results show that due to the presence of the monopile, the p_s of the soil around the pile increases whereas the p_s at the bottom of the monopile decreases. However, the p_s around the pile increases with increasing pile diameter. The bearing capacity of the monopile under the influence of wave load is less than that without wave load. At the same load, the pile settlement increases remarkably and the increase is more obvious in the case of larger pile diameter. The experiment shows that the effect of wave load on the pile foundation bearing capacity should be monitored during the design process.

Key words: wave load, monopile bearing capacity, wave flume experiment, excess pore pressure

CLC Number:

TU473.1

JIN Xiaokai, CHEN Jinjian, LIAO Chencong. Wave Flume Simulation Experiment on Influence of Wave Load on Bearing Capacity of Monopile[J]. Journal of Shanghai Jiao Tong University, 2021, 55(4): 365-371.

Figures/Tables 11

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名称	参数	实际值	试验值
1号模型桩	D/m	1.125	0.045
	L_m/m	32.5	1.3
	d/m	0.125	0.005
2号模型桩	D/m	1.625	0.065
	L_m/m	32.5	1.3
	d/m	0.125	0.005
波	T/s	7.5	1.5
波	H/m	3	0.12
水深	h_w/m	12.5	0.5

参数	参数值
ρ/(kg·m^-3)	2679
d₅₀/mm	0.215
e_max	0.892
e_min	0.643
e	0.812
D_r	0.321
E/(N·m^-2)	2.23×10⁷
G/(N·m^-2)	8.92×10⁶
ν	0.25
k/(m·s^-1)	2.382×10^-5