• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.44-51
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• 1998

A seismic attenuation formula is derived from the intensity maps of medium sized four earthquakes that occurred in the southern part of Korean peninsula. In order to obtain the seismic attenuation formula, the the coefficients of four attenuation equations representing the intensity maps are integrated using the proper weighting factors depending on the credibility of the data are assigned to. The proposed formula shows the trend of attenuation similar to the ones for the Eastern North America for the region within the epicentral distance of 200km, but produces higher attenuation at farther distances. Though the attenuation curve is not derived from the instrumental data, the result could be a useful tool for the analysis of seismic hazard in Korean peninsula.

• 한국지진공학회논문집
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• 제20권7_spc호
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• pp.517-526
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• 2016

In this paper, some popular intensity measures of earthquakes including magnitude, MMI, and PGA as well as their empirical relationships are briefly reviewed since they have been widely used without prudence by mass media, the public, and even the government when asking or expressing the seismic capacity of buildings. The basic concept of current seismic design is also presented in order to facilitate relevant discussions. It is emphasized that expressing the building seismic capacity simplistically in terms of seismological quantities or terminologies like magnitude and MMI is inherently irrational, may be misleading the stakeholders, and should be avoided. Alternative expressions, more rational and consistent with current seismic design philosophy and practice, are recommended.

• Computers and Concrete
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• 제29권 5호
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• pp.279-283
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• 2022

The seismic analytic collapse fragility of soil nail wall structures with a shotcrete concrete covering is investigated in this paper. The finite element modeling process has been well described. The fragility function evaluates the link between ground motion intensities and the likelihood of reaching a specific level of damage. The soil nail wall has been subjected to incremental dynamic analysis (IDA) from medium to strong ground vibrations. The nonlinear dynamic analysis of the soil nail wall uses a set of 20 earthquake ground motions with varying PGAs. PGD is utilized as an intensity measure, the numerical findings demonstrate that the soil nailing wall reaction is particularly sensitive to earthquake intensity measure (IM).

• 한국지진공학회논문집
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• 제22권6호
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• pp.323-332
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• 2018

Recent two moderate earthquakes (2016 $M_w=5.4$ Gyeongju and 2017 $M_w=5.5$ Pohang) in Korea provided the unique chance of developing a set of relations to estimate instrumental seismic intensity in Korea by augmenting the time-history data from MMI seismic intensity regions above V to the insufficient data previously accumulated from the MMI regions limited up to IV. The MMI intensity regions of V and VI was identified by delineating the epicentral distance from the reference intensity statistics in distance derived by using the integrated MMI data obtained by combining the intensity survey results of KMA (Korea Meteorological Administration) and 'DYFI (Did You Feel It)' MMIs of USGS. The time-histories of the seismic stations from the MMI intensity regions above V were then preprocessed by applying the previously developed site-correction filters to be converted to a site-equivalent condition in a manner consistent with the previous study. The average values of the ground-motion parameters for the three ground motion parameters of PGA, PGV and BSPGA (Bracketed Summation of PGA per second for 30 seconds) were calculated for the MMI=V and VI and used to generate the dataset of the average values of the ground-motion parameters for the individual MMIs from I to VI. Based on this dataset, the linear regression analysis resulted in the following relations with proposed valid ranges of MMI. $MMI=2.36{\times}log_{10}(PGA(gal))+1.44$ ($I{\leq}MMI$$MMI=2.44{\times}log_{10}(PGV(kine))+4.86$ ($I{\leq}MMI$$MMI=2.59{\times}log_{10}(BSPGA(gal{\cdot}sec))-1.02$ ($I{\leq}MMI$

• Earthquakes and Structures
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• 제5권3호
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• pp.321-341
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• 2013

This paper investigates earthquake response of reinforced concrete regular frames subjected to rebar corrosion. A typical four-story reinforced concrete frame is designed according to Turkish Earthquake Code in order to examine earthquake response. Then different levels of rebar corrosion scenarios are applied to this frame structure. The deteriorated conditions as a result of these scenarios are included loss in cross sectional area of rebar, loss of mechanical properties of rebar, loss in bond strength and variations in damage limits of concrete sections. The frame is evaluated using a nonlinear static analysis in its sound as well as deteriorated conditions. The rebar corrosion effect on the structural response is investigated by comparing the response of the frame in each scenario with respect to the sound condition of the frame. The results shows that the progressive deterioration of the frame over time cause serious reductions on the base shear and top displacement capacity and also structural ductility of the corroded frames. The propagation time, intensity, and extensity of rebar corrosion on the frame are important parameters governing the effect of rebar corrosion on earthquake response of the frame.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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• pp.209-214
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• 2000

Shaking table tests were performed to investigate dynamic behavior of a three dimensional flexible rectangular liquid storage tank. Response characteristics to the three components of translational motion and three component of rotational motion were studied. The aluminium tank was exposed to the shaking high enough to make it behave in nonlinear range. Only very limited amount of the data have been processed yet. Very interesting phenomena on the effects of non-symmetry have been observed and presented. Test results that show nonlinear behavior under the high intensity shaking are reported.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.93-98
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• 2000

The objective of this study is to investigate the results of researches which have been conducted throughout the world and in Korea concerning the behavior modes of masonry infill panels and frames. The influence of masonry infill panels on the seismic behavior of RC frames must be considered in the design and evaluation procedure though current code provisions do not generally require explicitly this consideration. However, since the level of the earthquake intensity in Korea is assumed to be moderate, the masonry infill panels may cause the different effect to the structure from those in high seismicity region and this difference should be studied in depth in the future.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.123-130
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• 1998

The probability of unseating failure of the bridge spans under earthquakes is investigated. Seismic excitations are simulated as nonstationary processes by combining a stationary process and an intensity function. For computational convenience, a simplified single-degree-of-freedom model is adopted, which retains the dynamic characteristics of the original brige motion in concern. The time history analysis for the developed single degree-of-freedom model are carried out to evaluate the response processes, and the probabilistic characteristics of response displacements are evaluated. The reliability analysis of the bridge against the unseating failure is performed with the statistical information of the maximum displacements of responses.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.212-219
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• 1998

Dynamic analyses are performed for the wood structure modeled as a SDOF hysteretic system. The hysteresis model presented is a modified version of Takeda model. The comparison between the results of numerical simulation and the experimental results show good agreements in overall tendencies. The response of wood structure subjected to artificially generated earthquakes considering site effects is studied. It appears that the response is very strongly influenced by the intensity and the frequency contents of the ground motion.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.217-222
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• 1999

Seismic design in low to moderate seismic regions has to be based on the characteristics of seismic risk ground motion and structural response in that region. The characteristics of seismic hazard in low to moderate seismic regions are reviewed briefly. The recent findings on the dynamic behavior subjected to the moderate intensity level of ground motion are summarized. The seismic design considerations in Easterm America China Australia Thailand and Hong Kong will be introduced, . The effort to adopt the limited ductility design in low to moderate seismicity regions will be reported. Finally research works that are required for the implementation of the limited design concept will be proposed.