Recently, the occurrence frequency of earthquake has increased in Korea, and the interests for seismic reinforcement of existing school buildings have been raised. To this end, the seismic performance evaluations for school buildings that did not accomplish the seismic design are required. In particular, this study checks the eigenvalue analysis, pushover curves, maximum base shears, performance points and story drift ratios, and then analyzes the seismic performance characteristics according to bracing configuration of steel frame system reinforcement. Also, this study presents the practical field application methods through the comparison of analysis results for the seismic performance characteristics.

In this study, centrifuge model tests were performed to evaluate the seismic response of multi-DOF structures with shallow foundations. Also, elastic time history analysis on the fixed-base model was performed and compared with the experimental results. As a result of the centrifuge model test, earthquake amplification at the fundamental vibration frequency of the soil (= 2.44 Hz) affected the third vibration mode frequency (= 2.50 Hz) of the long-period structure and the first vibration mode (= 2.27 Hz) of the short-period structure. The shallow foundation lengthened the periods of the structures by 14-20% compared to the fixed base condition. The response spectrum of acceleration measured at the shallow foundation was smaller than that of free-field motion due to the foundation damping effect. The ultimate moment capacity of the soil-foundation system limited the dynamic responses of the multi-DOF structures. Therefore, the considerations on period lengthening, foundation damping, and ultimate moment capacity of the soil-foundation system might improve the seismic design of the multi-DOF building structures.

The Gyeongju and Pohang earthquakes caused damages to many cultural properties; particularly, stone pagoda structures were significantly damaged among masonry cultural properties. To preserve these structures, it is necessary to understand their dynamic behavior characteristics under earthquakes. Analyses on such areas as deformation, frequency, maximum acceleration, permanent displacement, sliding, and rocking have to be performed. Although many analytical studies have already been conducted, dynamic behavior studies based on experiments are insufficient. Therefore, this study analyzed dynamic behavior characteristics by performing a shaking table experiment on a three-story stone pagoda structure at the Cheollongsa temple site damaged by the Gyeongju earthquake. As a result of the experiment, the displacements of stylobates did not occur significantly, but the tower body parts rotated. In particular, the rotation of the 1F main body stone was relatively larger than that of the other chief body stones because the 1F main body stone is relatively more slender than the other parts. In addition, the decorative top was identified as the component most vulnerable to sliding. This study found that the 1F main body stone is vulnerable to rocking, and the parts located on the upper part are more vulnerable to sliding.

In case of stone pagoda structures, the various construction types appear, and various damages occur due to exposure to the outdoors for a long time. Such damages can be classified into non-structural damages and structural damages. However, studies for the effects of structural damages on stone pagoda structures are insufficient. Accordingly, this study intends to perform structural modeling and structural analysis according to structural damages of stone pagoda structure, and to perform risk analysis through the fragility curve. So, we expects that this study gives a great contribution to the preservation and maintenance of stone pagoda structures under the various structural damages.

Phaya-Thon-Zu temple has a unique architectural style connected by the three temples, and cultural values are highly as murals remain on some of the walls. However, various damages in internal walls and vaults have occurred due to earthquake and environmental influences. In order to analyze these damages, accurate structural analysis is required, but structural modeling is difficult, because Phaya-Thon-Zu temple is the complex masonry structure which is stacked with small bricks. Therefore, this study intends to analyze the causes of damages by examining collapse mechanism for cross section and longitudinal section of vaults in the entrance hall and shrine by using thrust line analysis, which is a geometric method, and to compare it with the actual damage situation.

In this study earthquake records were collected for rock conditions that do not reflect seismic amplification by soil from global earthquake databases such as PEER, USGS, and ESMD. The collected earthquake records were classified and analyzed based on the magnitude and distance of earthquakes. Based on the analyzed earthquakes, the design response spectrum shape, effective ground acceleration, and amplification ratios for each period band are presented. In addition, based on the analyzed data, the story shear force for 5F, 10F, 15F, and 20F were derived through an analysis of the elastic time history for multi-DOF structures. The results from analyzing the rock earthquake record show that the seismic load tends to be amplified greatly in the short period region, which is similar to results observed from the Gyeongju and Pohang earthquakes. In addition, the results of the multi-DOF structure analysis show that existing seismic design criteria can be underestimated and designed in the high-order mode of short- and medium-long cycle structures.

Recently, the occurrence frequency of earthquake has increased in Korea, and many cultural assets have been damaged. Cheomseongdae is a valuable cultural assets that must be preserved historically and culturally. But, the masonry structure such as Chemseongdae is vulnerable to lateral forces. Therefore, in this study, structural modeling and dynamic analysis are performed to reflect the ground state and structural form of Cheomseongdae. Also, discrete element analysis technique is applied and dynamic behavior characteristics are analyzed according to earthquake load. For this purpose, displacements and stresses according to locations are reviewed and then swelling and distortion are analyzed.

The stone pagoda continued to be damaged by weathering and corrosion over time, and natural disasters such as earthquake are accelerating the destruction of cultural properties. Stone pagoda has discontinuous structure behavior and is very vulnerable to the seismic load acting in lateral direction. It is necessary to analyze various design variables as the contact surface characteristics play an important role in the dynamic behavior of stone pagodas. For this purpose, contact surface characteristics of stone pagoda can be classified according to surface roughness and filler type, and representative model is selected and structural modeling and analysis are performed using the discrete element method. Also, the seismic load according to the repetition period is calculated and the dynamic analysis is performed considering the discontinuous characteristics of the stone pagoda. Finally, the seismic behavior characteristics can be analyzed by the evaluation of stresses, displacements and structural safety.

The arched stone bridge has been continuously deteriorated and damaged by the weathering and corrosion over time, and also natural disaster such as earthquake has added the damage. However, masonry stone bridge has the behavior characteristics as discontinuum structure and is very vulnerable to lateral load such as earthquake. So, it is necessary to analyze the dynamic behavior characteristics according to various design variables of arched stone bridge under seismic loads. To this end, the arched stone bridge can be classified according to arch types, and then the discrete element method is applied for the structural modelling and analysis. In addition, seismic loads according to return periods are generated and the dynamic analysis considering the discontinuity characteristics is carried out. Finally, the dynamic behavior characteristics are evaluated through the structural safety estimation for slip condition.

Stone pagoda structures have continued to be aged due to the combination of various damage factors. However, some studies on nonstructural damage have been carried out, but assessment studies on structural damage have not been done in various ways. Therefore, in this study, structural and nonstructural influencing factors according to the damage types are classified and the damage assessment according to the structural influencing factors affecting the behavior of the stone pagoda structure is performed. In addition, the damage rating classification criteria for each type of structural damages or damage locations are presented, and the damage index is calculated by providing the criteria for the classification of damage according to the degree of damage to which the damage is caused. Therefore, this study can evaluate quantitatively the damage status of stone pagoda structures.

The Hong Nang Sida temple is a cultural heritage that must be preserved due to the historical and cultural values that are highly evaluated in the world. The main sanctuary of Hong Nang Sida temple, presumed to have been built in 11th to 12th centuries, has been exposed in the open air for a long time after the collapse. Therefore, it is necessary to reconstruct the original shape of the Hong Nang Sida temple to reflect the original shape. To do this, it is necessary to examine the overall structure according to the restoration shape. For this purpose, this study analyzes the construction and configuration types for main sanctuary Mandapa of Hong Nang Sida temple, and conducts structural modeling according to actual and restoration plans. The structural and behavioral characteristics are analyzed by comparing stress and displacement values by measurement locations. In addition, we will examine the vertical load distribution by the layers of each wall and cobel arch of the Mandapa using the load distribution method.

In Korea, the occurrence frequency of earthquakes has recently increased, compared with the past. So, the various damages for cultural properties due to earthquake can be expected, and especially fortress structure is vulnerable to earthquake. Therefore, the resonable seismic characteristics evaluation is required to secure the safety for fortress structure with the various construction and configuration types. Also, we should consider the various applied load conditions as design variables. To this end, this study classifies fortress structures according to the construction and configuration types, and then applies the discrete element method to model and analyze fortress structures. Finally, the seismic characteristics is evaluated through slip condition due to the analysis results considering the various design variables.

Cheomseongdae is the masonry stone structure with the cultural and historical values. But, this structure has the various damages such as cracks, gaps, slope variations and ground subsidence. So, the interests for the safety security in the structural parts have been increased. Therefore, this study performs the structural modelling which considers the several damage cases, and then evaluates the structural behavior characteristics through the discrete element analysis. Especially, this study checks the swelling and displacement gap of the whole structure and the separation between the neighboring members.

본 논문에서는 견고표적 피해분석 무기효과 계산 SW의 Framework에 대하여 기술하였다. 탄두의 침투이력, 기폭에 의해 발생되는 폭압, 폭압에 의한 구조 및 비구조 구성품 파괴가 이론식 및 경험식을 통해 계산되었다. 또한 사용자의 편의를 위해 손쉬운 UI가 설계되었으며, 각 해석 단계는 모듈화되어 향후 개선 및 보완이 용이하게 하였다.

The stone pagoda of Mireuk temple site is currently restoring through the repairing process. This stone pagoda has the various construction types in the inner and outer space. Therefore, the stress concentration and structural behavior need to be considered through the analysis of various construction patterns. To this end, this study presents the structural modelling and analysis considering the discrete element analysis technique to solve the discontinuum behavior between the stone elements. Also, this study performs the structural performance evaluation through the various design variables for the safety of stone pagoda. Through the analysis results, we can find out the small stress concentration in the several members. But, because the stresses and displacements are relatively small, we can secure the safety of the whole structure.

본 연구에서는 morphogenesis 기법의 L-system 모델을 사용하여 대공간 구조물의 형태 생성 방안을 제공하고자 한다. 이와 같은 L-system 모델은 일반적으로 식물의 성장 과정을 시각화하기 위해 적용되어 왔으나 본 연구는 이를 건축 분야에 적용하기 위한 프로세스가 제안된다. L-system 모텔은 크게 문자열 생성 단계와 문자열 분석 단계로 구성되어 있다. 문자열 생성 단계에서는 초기문자열로부터 최종 문자열을 생생하며, 문자열을 생성하기 위해서는 alphabet, axiom 및 rule에 대한 정의가 필요하다. 또한 문자열 해석 단계에서는 문자열의 의미 부여에 따라 다양하게 해석될 수 있다. 특히 다양한 적용 예제를 통해 대공간 구조물의 형태 생성 모델을 구현한다.

대공간 스페이스 프레임 구조물은 구조물의 목적 및 설계자의 의도와 함께 다양한 형상으로 구성될 수 있으며, 다양한 구조물 형식에 적용될 수 있다. 그러나 이러한 대공간 스페이스 프레임 구조물의 최적의 부재크기나 형상은 구조 엔지니어의 경험과 반복적인 해석 그리고 시행착오적인 방법 때문에 그 결정이 쉽지 않다. 따라서 본 논문에서는 설계자가 구조물의 최적 형상을 선택할 수 있는 방안을 제시하기 위해 먼저 타원형 및 볼트복합형과 같은 다양한 유형의 스페이스 프레임 구조물이 선정되며, 절점, 좌표 및 부재 생성을 위한 형상생성방법이 고려된다. 또한 스페이스 프레임 구조의 최적설계 절차에서 각 절점 좌표는 높이 변화나 링의 개수에 따라 변하게 되므로 최적설계 과정에서 절점파 부재의 자동생성기법이 적용된다. 다음으로 형상생성방법을 기반으로 한 형상생성모듈은 구조물의 최적화 단계에 앞서 설계자가 원하는 형상을 생성해주는 모듈이며, 최적화 단계에서는 해석 모듈과 최적화모듈이 연계된다. 마지막으로 예제 모델을 통해 형상생성방안 및 최적설계 방안의 효율성을 검토한다.

본 연구는 스페이스 트러스 구조물의 초기 형상을 결정하기 위해 밀도법을 이용한 위상최적화 기술을 고려하고자 한다. 대부분의 초기 형상설계는 다양한 최적화 방법을 활용하지 않고 설계자의 경험이나 시행착오적인 방법을 바탕으로 수행되고 있다. 이런 이유로 합리적이고 경제적인 최적화기술이 초기 형상설계에 도입되어야 한다. 따라서 본 연구에서는 스페이스 트러스 구조물을 대상으로 설계영역을 설정하고 위상최적화를 수행하여 최적의 재료분포를 찾은 뒤 크기최적화를 이용하여 최적부재 크기를 찾고자 한다. 이와 같이 밀도법을 이용한 위상 및 크기최적화를 병행하여 수행할 경우 합리적인 스페이스 트러스 구조물의 초기 형상을 도출할 수 있다.

본 연구에서는 지진하중을 받는 고층 RC 골조구조물의 횡변위를 정량적으로 제어할 수 있는 방안을 제시한다. 이를 위해 수학적인 일반성을 가지면서 큰 규모의 문제도 효율적으로 다룰 수 있는 근사화 개념을 도입하여 횡변위 구속조건식을 설정한다. 아울러 구조부재의 단면특성 관계식을 설정함으로써 설계변수의 수를 줄여주고, 초기에 주어진 단면형상이 최적설계 과정동안 계속 유지된다는 가정을 이용하여 최적설계결과에서 구해진 단면특성에 따라 부재단면크기를 산출하는 방안을 강구한다. 특히 근사화된 횡변위구속조건식을 정식화 하기 위해 동적 변위민감도해석 방안이 고려된다. 이와 같이 제시된 동적 강성최적설계 기법의 효용성을 검토하기 위해 10층과 50층 규모의 삼차원 RC 골조구조물 모델이 고려된다.

본 연구에서는 민감도 해석을 이용하여 전단벽-골조 구조시스템의 횡변위를 정량적으로 제어할 수 있는 강성최적설계방안을 제시하고자 한다. 이를 위해 먼저 골조와 전단벽요소 사이의 변위자유도 적합성 문제를 해결하기 위한 요소강성행렬을 구성하며, 또한 수학적계획법의 일반성을 유지하면서도 큰 규모의 문제도 효율적으로 다를 수 있는 근사화 재념을 도입하여 횡변위 구속조건식을 설정한다. 아울러 전단벽 및 골조부재의 단면특성 관계식을 설정함으로써 설계변수의 수를 줄여주고, 이를 이용하여 강성행렬도함수의 산정을 용이하게 한다. 특히 골조의 경우 초기에 주어진 단면형상이 최적설계 과정동안 계속 유지된다는 가정을 이용하여 최적설계결과에서 구해진 단면특성에 따라 부재단면크기를 산출하고, 전단벽은 사용자의 의도에 따라 두께 또는 부재길이를 재산정하는 방안을 강구한다. 이와 같이 제시된 강성최적설계기법의 효용성을 검토하기 위해 두 가지 형태의 20층 전단벽-골조 구조물의 예제가 고려된다.