| Summary: | 碩士 === 國立交通大學 === 土木工程系所 === 106 === In this study, the effects of the penetration of spudcan into sloping seabed were investigated. Ottawa sand was used as soil specimen. 1g physical model tests were conducted for the circular model spudcan with a diameter of 150 mm. Testing facilities used at the National Chiao Tung University consisted of the vertical loading system, soil bin, spudcan, and data acquisition system. The air-pluviation method was used to control the uniformity of the soil sand. With the slot opening of 10 mm and a drop distance 300 mm of soil particles, the very loose relative density of 18% was achieved. After the specimen was submerged in the soil bin, the air trapped in the specimen was removed by a suction pump. The relative density of the saturated loose sand was 26%. In this study, the sloping angles of seabed selected for testing were 0°, 1°, 2°, 3°, 4°, 5°, 6°, 8°, and 10°. Test results indicates, during spudcan penetration, the vertical forces acting on the spudcan decreased with increasing sloping angle of seabed. The vertical force acting on the spudcan measured when penetrating a horizontal seabed was higher than the theoretical value estimated with the equation in SNAME (2008) by 23%. The horizontal forces acting on the spudcan increased with increasing sloping angle of the seabed. The measured horizontal force acted on the spudcan increased with increasing depth, until the maximum penetration depth 0.5D was reached. The bending moment acting on the spudcan reached a maximum value when the spudcan edge point touched the inclined seabed. On the longitudinal profile of the footprint, the inclination angle for both the uphill and downhill slope walls was 29.1 degree. Settlement at toe of the footprint was not affected by the inclination of the seabed. The maximum settlement in the footprint was about half the diameter of the spudcan.
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