Generally the non-bearing walls in apartment buildings in Korea are not considered as a lateral force resisting members for the design consideration. This engineering practice caused large crack damages and brittle fractures of the non-bearing walls when subjected to Pohang earthquakes in 2017 since those have not been designed for seismic loading. In this study, finite element analysis was conducted for slot type non-bearing wall connection system to reduce damages and concentrate damages to the designated damping device through separation from the structural wall members. Steel plate and dowel bar systems designed for the dissipation of seismic energies were modeled and analyzed to investigate the damage reductions. Finally, the test result and the analysis result were compared and verified.
This study introduces a newly developed PC non-bearing wall system to prevent the damage of RC wall-type apartments that have been heavily damaged by the 2017 Pohang Earthquake. In order to evaluate the performance of the developed PC non-bearing wall system, a static cyclic test is conducted. The prototype of test specimen is from the RC wall-type apartment which has been severely damaged by the 2017 Pohang Earthquake. The specimen with the conventional non-bearing wall system showed the similar damage of RC wall type apartment suffered from the Pohang Earthquake. In case of the specimen with the developed PC non-bearing wall system, cracks and damages were not transmitted between the walls due to the seismic slit and there were almost no cracks in the non-bearing walls. Therefore, the proposed non-bearing wall system, separated from the structural walls, could prevent spreading cracks to bearing walls and make it possible to effectively control damage due to earthquake loads.
In 2017 Pohang Earthquake, a number of residential buildings with pilotis at their first level were severely damaged. In this study, the results of an analytical investigation on the seismic performance and structural damage of two bearing wall buildings with pilotis are presented. The vibration mode and lateral force-resisting mechanism of the buildings with vertical and plan irregularity were investigated through elastic analysis. Then, based on the investigations, methods of nonlinear modeling for walls and columns at the piloti level were proposed. By performing nonlinear static and dynamic analyses, structural damages of the walls and columns at the piloti level under 2017 Pohang Earthquake were predicted. The results show that the area and arrangement of walls in the piloti level significantly affected the seismic safety of the buildings. Initially, the lateral resistance of the piloti story was dominated mainly by the walls resisting in-plane shear. After shear cracking and yielding of the walls, the columns showing double-curvature flexural behavior contributed significantly to the residual strength and ductility.
본 연구에서는 지진하중을 받는 교량구조물의 동적거동을 보다 실제적으로 예측하기 위하여 받침의 손상여부는 물론 다양한 영향요소를 고려할 수 있는 이상화된 다자유도 교량해석모형을 개발하였으며, 이를 바탕으로 받침의 손상이 교량구조물의 지진응답에 미치는 영향을 분석하였다. 받침의 손상은 마찰요소를 이용한 단순화된 모형으로 고려하였으며, 발생가능한 받침의 손상조건에 따른 영향을 분석하기 위하여 다양한 마찰계수의 적용에 따른 교량구조물의 응답분포특성을 구하였다. 모의분석 결과로부터 받침손상의 고려여부 및 적용된 마찰계수에 따라 최대응답의 크기 및 발생위치가 서로 다르게 평가되었으며, 특히 교량구조물에서 낙교의 발생가능성이 큰 위치에서의 최대상대거리는 받침의 손상여부에 따라 상당한 영을 받는 것으로 나타났다. 그러나 최대응답의 증가량은 크지 않은 것으로 분석되었다. 그러므로 다경간 단순형 교량구조물에 있어서 받침의 손상에 따른 낙교의 발생가능성을 감소시키기 위한 부가적인 받침보강은 필요시 선택적으로 적용될 수 있을 것으로 판단된다.