• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.93-101
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• 2011

Korea has about 70% of its land classified as the mountain area, which has led to cut-slope being the result of substantial road and railway construction. However, there is currently a lack of research about the seismic retrofit design of a slope, even though many earthquakes have recently occurred at home and abroad. In this study, in order to investigate the stabilizing effect of piles against sliding during an earthquake, a series of 1 g shaking table tests and pseudo-static analyses were carried out. As a result, the stabilizing effect of piles against sliding during an earthquake was verified by the 1 g shaking table tests and the most effective result from the pseudo-static analyses was that the installation of the piles on the central part of the slope, where the failure surface included piles unlike the lower part and upper part of the slope. Furthermore, when the pile was installed on the central part of the slope, the change of the safety factor depending on the distance between the center of two piles was evaluated.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.755-758
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• 2010

본 연구에서는 토목구조물에 대하여 상사율을 고려한 1g 진동대실험(Shaking Table Test)과 전산해석을 수행하여, 실제 지진하중(단주기, 장주기, 인공지진)에 대한 토목구조물의 안정성을 분석 및 평가 하였다. 상사율에 따른 지표면 가속도 거동을 비교 분석하기 위하여 여러 가지 상사율을 적용한 실험을 수행하여 측정된 결과와 전산해석 결과를 상호 비교 분석하여 상사비에 따른 실험결과의 적절성을 평가하였다. 상사율을 1/50과 1/50보다 크게 조성하여 진동대실험과 전산해석 결과에 의하면, 지표면 가속도의 결과는 모두 유사한 결과를 보였다. 상사율 1:50 이상인 단면의 경우 진동대실험과 전산해석 결과 사이의 유사성이 떨어지는 것으로 볼 때, 1:50 이하인 상사단면이 실제 현장에서의 거동을 모사하는데 더 높은 신뢰성을 제공하는 것으로 판단된다.

• 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.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.5 s.39
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• pp.79-89
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• 2004

This paper presents the results of experimental studies on the equipment isolation effect in the nuclear containment. For this purpose, shaking table tests were performed. The purpose of this study is enhancement of seismic safety of equipment in the Nuclear Power Plant. The isolation system, known as Friction Pendulum System (FPS), combines the concepts of sliding bearings and pendulum motion was selected. Peak ground acceleration, bidirectional motion, effect of vertical motion and frequency contents of selected earthquake motions were considered. As a result, these are founded that the vertical motion of seismic wave affect to the base isolation and the isolation effect decreased in case of near fault earthquake motion.

• Journal of the Korean Geotechnical Society
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• v.33 no.7
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• pp.17-28
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• 2017

This paper presents the investigation of dynamic behavior of a single pile in dry sand based on 1g shaking table tests. The natural frequency of soil-pile system was measured, and then a range of loading frequency was determined based on the natural frequency. Additionally, the studies were performed by controlling loading accelerations, pile head mass and connectivity conditions between pile and cap. Based on the results obtained, relatively larger pile head displacement and bending moment occur when the loading frequency is larger than the natural frequency of soil-pile system. However, the slope of the p-y curve is smaller in the similar loading frequency. Also, it was found that inertia force like input acceleration and pile head mass, and relation of the natural frequency of soil-pile system and input frequency have a great influence on the slope of dynamic p-y curve, while pile head conditions don't.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.2
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• pp.177-186
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• 2005

World widely, the occurrences of earthquakes have been increased recently including to nations which earthquake often happen to like Japan. Taking into account that the earthquake acceleration at design was 0.154 g at the contigency level earthuake (CLE) with its geological condition, it resulted that this method must be the most efficient condition against the earthquake vibration to two lane cut-and cover tunnel. The correlations between the result of the shaking table test and its numerical analysis showed that the test data of the bending stress due to the earthquake vibration have been underestimated about 5 percents in case of the cut slope 1 : 0.6 and about 10 percent in case of the cut slope 1 : 1.2. However, on average, the results showed a similar tendency that the higher the height of the backfill of the EPS block was, the less the bending stress was.

• Journal of the Korean Geotechnical Society
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• v.26 no.8
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• pp.67-75
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• 2010

In this study, a series of 1 g shaking table tests were carried out for a single pile in soft clay with various input acceleration amplitudes and frequencies. Based on the results, dynamic p-y curves were drawn and, in turn, the dynamic p-y backbone curve was formed by connecting the peak points, corresponding to the maximum soil resistance, of the dynamic p-y curves. In order to represent the p-y backbone curve numerically, Matlock's p-y formulations for clay was used to find the initial stiffness ($k_{ini}$) and the ultimate capacity ($p_u$) of the clay, both of which are required to formulate the p-y backbone curve as a hyperbolic function. The suggested p-y backbone curve was verified through comparisons with currently available p-y curves as well as other researchers' centrifuge test results and numerical analysis results.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.535-545
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• 2022

Improving the stability of the ground in seismic design requires an understanding of the dynamic behavior of the ground under seismic loads. The shaking table test is an important methodology to provide this understanding. This study aimed to assess the influence on boundary conditions, as they are among the most important factors affecting the test. This was achieved by testing the influence of boundary conditions on the seismic responses of model slopes at different locations in the testing apparatus. A model slope was fabricated at different locations in a laminar shear box, and the influence of the boundary conditions was then measured. Each model slope was created at 100, 50, and 25 cm from the soil wall, and sine wave seismic loads of the same size were inputted. The results confirmed that the acceleration was amplified by the influence of the boundary in the case of the slope being located 25 cm from the boundary, whereas the influence of the boundary conditions decreased when the slope was located at 50~100 cm.

• The Journal of Engineering Geology
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• v.32 no.1
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• pp.143-155
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• 2022

In this study, the response acceleration amplification according to different conditions was analyzed by changing the boundary condition of the soil called LSB (Laminar Shear Box), which is placed on a 1 g shaking table for earthquake simulation experiments. Experiments were carried out with different boundary conditions by fixing both sides of the LSB, and two samples were tested by installing an accelerometer at the same location. In addition, using DEEPSOIL v7 program, a one-dimensional ground response analysis was performed to compare and analyze with the free field condition. As a result, it was confirmed that the acceleration was amplified as it went from the lower layer to the upper layer, and as a result of comparing it with the ground response analysis, it was confirmed that it appeared similar to the analysis under the free field condition. As a result of the SA (Spectrum acceleration) analysis, a result similar to that of the ground response analysis was obtained, and in the case of fixing, it was confirmed that the PSA (Peak Spectral Acceleration) was further amplified.

• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.241-252
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• 1998

The objective of the research stated herein is to observe the actual responses of a low-rise nonseismic moment-resisting reinforced concrete frame subjected to varied levels of earthquake ground motions. First, the reduction scale for the model was determined as 1 : 5 considering the capacity of the shaking table to be used and the model was manufactured according to the similitude law. This model was, then, subjected to the shaking table motions simulating Taft N21E component earthquake ground motions, whose peak ground accelations (PGAs) were modified to 0.12g, 0.2g, 0.3g, and 0.4g. The lateral accelerations and displacements at each story and local deformations at the critical reginos of the structure were measured. The base shear was measured by using self-made load cells. Before and after each earthquake simulation test, free vibration tests were performed to find the change in the natural period and damping ratio of the model. The test data on the global and local behaviors are interpreted. The model showed the linear elastic behavior under the Taft N21E motion with the PGA if 0.12g, which represents the design earthquake in Korea. The maximum base shear was 1.8tf, approximately 4.7 times the design base shear. The model revealed fairly good resistance to the higher level of earthquake simulation tests. The main components of its resistance to the high level of earthquakes appeared to be 1) the high overstrength, 2) the elongation of the fundamental period, and 3) the minor energy dissipation by inelastic deformations. The drifts of the model under these tests were approximately within the allowable limit.