Experimental investigations on the stability of clayey sloping seabed under wave actions

Many offshore marine structures are built on seabeds with slight or considerable slopes, while most analytical studies have focused on the dynamic responses of horizontal seabeds. Based on the theory of porous media, an analytical solution for the response of a sloping seabed to earthquakes is developed in this paper. Stress and displacement responses can be shown at any location of the seabed.Using numerical examples, we analyze the influence of the slope angle, frequency and angle of incident waves, and thicknesses of the seawater and sediment layers on the dynamic response of the seabed. The results show that the solid displacement amplification factor of the surface of the horizontal seabed is always constant, while that of the sloping seabed changes periodically along the seabed surface. Even at a small site, the difference between a horizontal seabed and a sloping seabed is still significant. The slope angle has different effects on the seabed at different depths, and the inclination plays an amplification role at some depths and a reduction role at other depths. With an increase in slope angle, the difference between a horizontal seabed and a sloping seabed becomes more significant. Especially at natural frequencies, the amplification factor becomes more significant with increasing slope angle. Therefore, even though the same seawater depth is used in the model, a horizontal seabed model cannot be used to analyze the dynamic response of a sloping seabed or significant errors will occur.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An analytical solution for the dynamic response of a seawater‐sloping seabed‐bedrock system under an oblique incident P wave

Shan

Xie

Dong

et al. 2023

“…Many scholars also take the seabed slope characteristics into account when studying the dynamic response of the seabed. 21,22 Rafiei et al 21 investigated the dynamic response of sloping seabed under wave action and seabed liquefaction by numerical simulation. Dou et al 22 conducted a series of wave flume tests to investigate the response of a clayey sloping seabed under wave action.…”

Section: Introductionmentioning

confidence: 99%

“…21,22 Rafiei et al 21 investigated the dynamic response of sloping seabed under wave action and seabed liquefaction by numerical simulation. Dou et al 22 conducted a series of wave flume tests to investigate the response of a clayey sloping seabed under wave action. The above studies either ignore the effect of seabed slope terrain or the role of currents, and none of them consider the cumulative effect of excess pore pressure under wave cycling.…”

Section: Introductionmentioning

confidence: 99%

Mechanical response of shield tunnel lining under nonlinear wave and current action in sloping seabed

Zhang,

Han,

et al. 2023

With the increasing demand for transportation construction in coastal areas, tunnel safety research is becoming increasingly important. Previous studies take less account of the nonlinear wave and current action under the sloping seabed terrain. Furthermore, there are few researches on the additional deformation of shield tunnel lining caused by wave‐current dynamic pressure. In this paper, according to the interaction theory of Stokes third‐order nonlinear wave and uniform current and Biot's dynamic consolidation equation, the excess pore pressure response of sloping pure seabed under the wave‐current action is obtained. The excess pore pressure reflected by the tunnel is acquired using the seepage continuity condition on the permeable lining surface. Considering the residual excess pore pressure caused by the cumulative effect under the cyclic action of seepage force. Then the distribution law of seepage pore pressure around the shield tunnel in the sloping seabed under the wave‐current action is obtained based on the superposition principle. The displacement response of tunnel lining during the long‐term service period is obtained by combining the exponential decay model. Moreover, the accuracy of theoretical analysis is verified by experimental monitoring data and numerical simulation, and the hydraulic parameters, seabed parameters and tunnel parameters are analyzed.

“…With the gradual increase in marine engineering, the hazards of seismic loads and seawater wave loads to the stability of sea infrastructure and seabed have also received increasing attention. The marine structures on the sloping seabed has attracted increasing attention, including research on pipelines (Xu et al 1 ; Seyfipour and Walker 2 ; Rafiei et al 3 ), wind turbines (Ti and Deng, 4 ), oscillating water column (OWC) devices (Khan and Behera, 5 ), embankments (Zhao and Jeng 6 ; Ni and Teng 7 ), small marine structures (Rafiei et al 8,9 ), and slope stability (Feng and Price 10 ; Dou et al 11 ). All of these studies have concentrated on the dynamic responses of the seabed and structures induced by seawater waves.…”

Section: Introductionmentioning

confidence: 99%

An analytical solution for the dynamic response of a seawater‐sloping seabed‐bedrock system under an oblique incident SV wave

Shan,

Xie,

et al. 2023

The characteristics of seabed ground motion are the theoretical basis for the study of seawater‐soil‐structure interactions and seismic‐induced geological hazards. There are numerous offshore marine structures located on sloping seabeds. Therefore, the sloping seabed's seismic response requires to be investigated. Engineers and scholars are more interested in the SV waves because they carry more energy than the P waves in earthquakes. An analytical solution for the steady‐state response of the inclined seafloor under an oblique incident SV wave is offered. The impacts of the seafloor angle on the fluid pressure and displacement of the saturated sediment layer are investigated under different incident wave frequencies, incident angles, and thicknesses of the seawater layer and sediment layer. By observing along the seabed surface, we discovered that the slope angle might cause considerable variances between different positions even at a small site. While examining the seabed at varying depths, we discovered that the incline angle has distinct impacts on different areas of the seabed. It has an amplifying effect at some depths and a reducing effect at other depths. Generally, as the slope angle increases, the distinction between the responses of the inclined and horizontal seabed becomes more prominent. Especially when the incidence angle of the SV waves is near the critical angle, the impacts of the slope angle become more significant. Even if the horizontal seabed model is employed with the same seawater depth, it is not suitable for analyzing the seismic response of a sloping seabed. Otherwise, significant errors would arise.