• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.4
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• pp.232-239
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• 2016

In this study, the two-way coupled analysis method of LES-WASS-2D and DEM has been newly developed to review numerically wave attenuation due to behavior of vegetation zone could not yet applied in numerical analysis. To verify the applicability, two-way coupled analysis method is analyzed comparing to the experimental result about characteristics of wave attenuation using vegetation. Numerically analyzed behavior and characteristics of wave attenuation according to height length, distribution length, spacing of vegetation zone and incident wave conditions. It was confirmed to be effective of 3~4% wave attenuation were increased height length and distribution length, narrowed spacing of vegetation. Finally, this study is applicable to behavior and wave attenuation prediction of vegetation zone.

• Journal of Ocean Engineering and Technology
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• v.23 no.1
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• pp.31-37
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• 2009

Coastal vegetation consists of rooted flowering marine plants that provide a variety of ecosystem services to the coastal areas they colonize. The attenuation of currents and waves and sediment stabilization are often listed among these services. From this point of view, artificial seaweed is an effective method of controlling sea bed sediment and stabilization without damaging the landscape or the stability of the coastline. A series of hydraulic experiments were performed in a wave channel with regular and irregular waves to examine the effect of artificial seaweed in relation to scouring and beach erosion prevention. Based on the results of these experiments, the coastal vegetation model is efficient against scouring and beach erosion.

• Journal of the Korean GEO-environmental Society
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• v.20 no.12
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• pp.15-26
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• 2019

This study was conducted to characterize shearing strength of geotextile bag, connecting materials and gabion. A largescale shaking take tests were conducted to assess kinetic characteristics of gabion-geotextile bag retaining wall. Based on the results of large-scale shaking table test, dynamic characteristics of gabion-geotextile bag retaining wall structure against acceleration, displacement, and earth pressure were also analyzed. The increments of dynamic active earth pressure were determined to be (0.376-0.377)H at 1:0.3 slope and $(0.154-0.44)g_n$ earthquake acceleration, and (0.389-0.393)H at 1:1 slope, suggesting that the increments tend to rise as the slope decreases.

• Geotechnical Engineering
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• v.11 no.2
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• pp.29-36
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• 1995

Load testis are executed on model reticulated root piles (RRP) to figure out the optimum slanting angle in the piles installation. One set of model RRP consists of 8 slanting piles which are installed in circular patterns forming two concentric circles, each of which is made by 4 piles. Each pile which is a steel bar of 5m in diameter and 300mm in length is coated to become a pile of 6.5mm in diameter. The slanting angle of the model RRP varies from 0$^{\circ}$ to 20$^{\circ}$ Comparing ultimate bearing capacities of the model RRP of different installation angles, it is observed that the ultimate capacities of the RRP increase as the installation angle increases until 15$^{\circ}$, and the optimum slanting angle of the RRP is around 15$^{\circ}$ The ultimate bearing capacity of the 15$^{\circ}$-RRP is found to be 22% bigger than that of the vertical RRP and 120% bigger than that of the circular surface footing whose diameter is same with the circle formed by outer root piles'heads. However, it is noticed that when the slanting angle of the RRP is increased over 15$^{\circ}$, the ultimate capacity starts to be reduced. The ultimate capacity of 20$^{\circ}$-RRP is even smaller than that of the vertical RRP by as much as 5%. From the observation of the load settlement curve obtained during the RRP load tests, it is known that as the slanting angle gets bigger the load -settlement behavior becomes more ductile.