An experimental study of seabed responses around a marine pipeline under wave and current conditions

TY - JOUR

T1 - An experimental study of seabed responses around a marine pipeline under wave and current conditions

A1 - Zhou,Chunyan

A1 - Li,Guangxue

A1 - Dong,Ping

A1 - Shi,Jinghao

A1 - Xu,Jishang

AU - Zhou,Chunyan

AU - Li,Guangxue

AU - Dong,Ping

AU - Shi,Jinghao

AU - Xu,Jishang

PY - 2011/1

Y1 - 2011/1

N2 - <p>Experiments on three types of soil (d(50) = 0.287, 0.057 and 0.034 mm) with pipeline(D = 4 cm) either half buried or resting on the seabed under regular wave or combined with current actions were conducted in a large wave flume to investigate characteristics of soil responses. The pore pressures were measured through the soil depth and across the pipeline. When pipeline is present the measured pore pressures in sandy soil nearby the pipeline deviate considerably from that predicted by the poro-elasticity theory. The buried pipeline seems to provide a degree of resistance to soil liquefaction in the two finer soil seabeds. In the silt bed, a negative power relationship was found between maximum values of excess pore pressure Amy, and test intervals under the same wave conditions due to soil densification and dissipation of the pore pressure. In the case of wave combined with current, pore pressures in sandy soil show slightly decrease with time, whereas in silt soil, the current causes an increase in the excess pore pressure build-up, especially at the deeper depth. Comparing liquefaction depth with scour depth underneath the pipeline indicates that the occurrence of liquefaction is accompanied with larger scour depth under the same pipeline-bed configuration. (C) 2010 Elsevier Ltd. All rights reserved.</p>

AB - <p>Experiments on three types of soil (d(50) = 0.287, 0.057 and 0.034 mm) with pipeline(D = 4 cm) either half buried or resting on the seabed under regular wave or combined with current actions were conducted in a large wave flume to investigate characteristics of soil responses. The pore pressures were measured through the soil depth and across the pipeline. When pipeline is present the measured pore pressures in sandy soil nearby the pipeline deviate considerably from that predicted by the poro-elasticity theory. The buried pipeline seems to provide a degree of resistance to soil liquefaction in the two finer soil seabeds. In the silt bed, a negative power relationship was found between maximum values of excess pore pressure Amy, and test intervals under the same wave conditions due to soil densification and dissipation of the pore pressure. In the case of wave combined with current, pore pressures in sandy soil show slightly decrease with time, whereas in silt soil, the current causes an increase in the excess pore pressure build-up, especially at the deeper depth. Comparing liquefaction depth with scour depth underneath the pipeline indicates that the occurrence of liquefaction is accompanied with larger scour depth under the same pipeline-bed configuration. (C) 2010 Elsevier Ltd. All rights reserved.</p>

KW - Pore pressure

KW - Pipeline

KW - Liquefaction

KW - Regular wave

KW - Current

KW - Soil response

KW - INDUCED FORCES

KW - WATER-WAVES

KW - SOIL

KW - LIQUEFACTION

KW - BED

KW - CONSOLIDATION

KW - FLUIDIZATION

UR - http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-78651486628&md5=261b49dd4d19ea88c82aec1abc33f4d2

U2 - 10.1016/j.oceaneng.2010.10.006

DO - 10.1016/j.oceaneng.2010.10.006

M1 - Article

JO - Ocean Engineering

JF - Ocean Engineering

SN - 0029-8018

IS - 1

VL - 38

SP - 226

EP - 234

ER -