• KCI Concrete Journal
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• v.11 no.3
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• pp.153-164
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• 1999

The objective of this research is to observe the actual response of a low-rise nonseismic moment-resisting masonry-infilled reinforced concrete frame subjected to varied levels of earthquake ground motions. The reduction scale for the model was determined as 1 : 5 considering the capacity of the shaking table to be used. This model was, then, subjected to the shaking table motions simulating Taft N2IE component earthquake ground motion, whose peak ground acceleration(PGA) was modified to 0.12g, 0.2g, 0.3g, and 0.4g. The g1oba1 behavior and failure mode were observed. The lateral accelerations and displacements at each story and local deformations at the critical portions of the structure were measured. Before and after each earthquake simulation test, free vibration tests and white noise tests were performed to find the changes in the natural period of the model. When the results of the masonry-infilled frame are compared with those of the bare frame, it can be recognized that masonry infills contribute to the large increase in the stiffness and strength of the g1oba1 structure whereas it also accompanies the increase of earthquake inertia forces. However, it is judged that masonry infills may be beneficial to the performance of the structure since the rate of increase in strength appears to be greater than that of the induced earthquake inertia forces.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.905-912
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• 2009

1-g shaking table test is conducted to evaluate the dynamic behavior of a soil-structure system under seismic loading condition. A consistent similitude law between the model and prototype is needed to predict the behavior of the prototype structure, quantitatively. The natural frequency of geomaterial decreases with the increase of shaking intensity because of the non-linear property of the geomaterial. This phenomenon affects the applicability of similitude laws in 1-g shaking table tests. In this study, a simple method is suggested to determine the frequency of the input motions in 1-g tests in order to enhance the applicability of similitude laws. Modified input frequency is calculated using the frequency ratio with consideration of the variation of the natural frequency according to the intensity of input ground acceleration. To verify the applicability of the suggested method, a series of 1-g shaking table tests were performed for three different sizes of model piles having an overburden mass on their heads by varying the acceleration and the frequency of input motion. The acceleration amplification ratio on the overburden mass, the lateral displacement at the pile head and the maximum bending moment along the pile depth were measured. The projected behaviors of the virtual prototype based on the measured values of the model tests, where the input frequencies were calculated by the new method, showed good consistency, verifying the applicability of the suggested method.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.721-728
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• 2006

Earthquakes are reported thai building structures have been colossal damaged, but before 1988 designed structures which were not applicate seismic design code have no seismic performance. Especially, for the apartment structures were indicated that it have no resist wall element of earthquake before 1988 designed structures. We have to evaluate for seismic performance this structures, therefore it will be retrofitted for seismic index sufficient structures. We performed seismic performance evaluation for model structures by MIDAS which is general structure analysis software. In this study, it was performed shaking table test to evaluate model structure which is reinforcement concrete and 5 floors for seismic performance index. We made specimens by similar's law and tested shaking table test. In the shaking table test it is not performed prototype model test because of space and equipment condition. So we had made scale-down model for 1/5 by similar's law. That's why it needs for the evaluation of performance. However, it is not possible to do an experiment of prototype owing to the shortage of space and the limit of an experimental instrument in the shaking table test. Then, modeling and reducing the part of prototype do the experiment. In this experiment a shaking table test is done and seismic performance of model structures is evaluated by using similitude laws for scale down specimen. As a result it is proved that non-seismic design structures need to retrofit since seismic performance shows life safe grade in 0.12g of an earthquake.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.3
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• pp.503-515
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• 2017

Underground structures that have recently become larger are required to be stable not only during normal times but also during earthquakes. Especially, it is very important to maintain the stability of the subsea tunnels during the earthquake. The objective of this paper is to verify the effectiveness of the flexible segment, which is one of the breakthrough facilities to maintain the stability of the subsea tunnel during the earthquake using the shaking table test. Another goal of this paper is to propose the optimum position of the flexible segment through 3D dynamic numerical analysis based on the verified results from shaking table tests. The 1g shaking table test considering the similarity ratio (1:100) to the cross section of the selected artificial subsea tunnel was carried out considering the Geongju and Artificial seismic waves, longitudinal and lateral wave, and with/without flexible segments eight times or more. As a result of the shaking table test, it was confirmed that the flexible segment is effective in improving the seismic performance of the undersea tunnel in all the experimental results. In addition, 3D dynamic numerical analysis was performed to select the optimum position of the flexible segment which is effective for improving seismic performance. As a result, it was confirmed that the seismic acceleration is attenuated when the flexible segment is installed adjacent to the branch section in subsea tunnel.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.139-144
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• 2001

The objective of this study is to investigate the behavior of 1/12 scale upper-wall lower-frame reinforced concrete structure subjected to earthquake excitations. For this purpose, Taft N21E earthquake accelerogram was simulated by using 4m$\times$4m shaking table. When the input acceleration is compared to that of output, it was found that simulation of shaking table is satisfactory. From the test results with peak ground acceleration(PGA) 0.22g, which corresponds to 0.11g in prototype by the similitude law, it can be observed that the model responded in elastic behavior and that large interstory drift occurred at the lower part of the structure.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.7 s.100
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• pp.806-812
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• 2005

This paper adresses the shaking table tests with 1/100 scaled model followed similitude law for OOdam main designing section to understand nonlinear behavior characteristics of concrete dam body by ground motion. As earthquake wave, Hachinohe and El Centre waves were used and acceleration and displacements are measured to analyze behaviors of dam body. For maximum ground acceleration range $(0.3\~0.9 g)$, the results showed linear behavior regardless of maximum 9round acceleration and secured safety of structure. To analyze the behavior of dam after tension cracking, 3 cm-notch was placed at the critical section of over-flowing section. As results of applying Hachinohe wave(0.8 g), Even though tension cracks were formed at over-flowing section by Hachinohe wave(0.8 g), it showed that the dam is stable for supporting upper stream Part of water tank of dam.

• 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.

• Earthquakes and Structures
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• v.23 no.6
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• pp.517-526
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• 2022

Previous studies have shown that pile-soil interactions have significant influences on the isolation efficiency of an isolated structure. However, most of the existing tests were carried out using a 1-g shaking table, which cannot reproduce the soil stresses resulting in distortion of the simulated pile-soil interactions. In this study, a centrifuge shaking table modelling of the seismic responses of a friction pendulum bearing isolated structure with a pile foundation under earthquakes were conducted. The pile foundation structure was designed and constructed with a scale factor of 1:100. Two layers of the foundation soil, i.e., the bottom layer was made of plaster and the upper layer was normal soil, were carefully prepared to meet the similitude requirement. Seismic responses, including strains, displacement, acceleration, and soil pressure were collected. The settlement of the soil, sliding of the isolator, dynamic amplification factor and bending moment of the piles were analysed to reveal the influence of the soil structure interaction on the seismic performance of the structure. It is found that the soil rotates significantly under earthquake motions and the peak rotation is about 0.021 degree under 24.0 g motions. The isolator cannot return to the initial position after the tests because of the unrecoverable deformation of the soil and the friction between the curved surface of the slider and the concave plate.

• Journal of the Korean Geotechnical Society
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• v.20 no.3
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• pp.141-150
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• 2004

Shaking table model tests were performed to reproduce the dynamic behavior of a gravity quay wall and a pile-supported wharf which were damaged during the Kobe earthquake in 1995. The results of the model tests were compared with field measurements and with the results of previous model tests. The displacements of the model quay wall were only one third of that of the prototype, whereas the deformation state of the model was similar to that of the prototype. The displacements of the model pile-supported wharf were about two thirds of that of the prototype and the locations of the maximum moments at the model pile were similar to the buckling locations of the prototype piles.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.841-848
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• 2021

This study investigated the acceleration characteristics of rock slopes when earthquakes, which have not been studied much in Korea, occur. The rock slope was modeled with a similar raw of 1/20 in consideration of the height(10m), roughness, strength, and the joint dips(20°). After the completion of the model, a shaking table tests was conducted according to the magnitude of the acceleration and the type of seismic wave. The maximum acceleration was greater in the short-period seismic wave than in the long-period seismic wave, and the maximum acceleration was larger in the small acceleration. The rock slope was close to a rigid block and a structure more vulnerable to the long period wave than to the short period wave. In the event of an earthquake smaller than the domestic earthquake-resistant maximum design acceleration(0.154g), safety management of the rock slope was required.