• Title/Summary/Keyword: 조적

Search Result 121, Processing Time 0.034 seconds

Shear Strength Evaluation of Unreinforced Masonry Walls Using Pushover Analysis (푸쉬오버 해석을 통한 비보강 조적벽체의 전단강도평가)

  • Lee, Jung-Han;Kim, Hye-Won;Kim, Jin-Seon;Park, Byung-Cheol;Yi, Waon-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2010.04a
    • /
    • pp.746-749
    • /
    • 2010
  • 본 연구에서는 비보강 조적조에 대한 부재 비선형거동 및 비탄성힌지 속성을 고려할 수 있는 midas GEN Ver.741(해외판) 프로그램에 의한 비보강 조적벽체의 푸쉬오버 해석결과와 실험결과와의 비교를 통하여 비보강 조적조 건축물의 전단강도평가를 비롯하여 내진성능평가를 위한 역량스펙트럼 해석 프로그램을 검증하고자 한다. midas GEN Ver.741(해외판) 프로그램의 사용성 검증을 위하여 조적벽체의 축하중, 형상비, 쌓기방법(두께) 그리고 개구부 유무를 변수로 한 10개의 비보강 조적벽체의 전단강도를 비교 평가한다. 비보강 조적벽체에 대한 실험결과와 해석결과를 비교한 결과 각 시험체별 전단강도 값이 비교적 유사한 것으로 나타나며 국내 기존 비보강 조적조 건축물에 대한 해석방법으로 본 프로그램의 사용이 가능한 것으로 평가되었다.

  • PDF

Inelastic Behavior of Reinforced Concrete Frame Structure with Shear Strength of Masonry Wall (조적벽의 전단강도를 고려한 철근콘크리트골조의 비탄성 거동)

  • Yoon, Tae-Ho;Kang, Kyung-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.9
    • /
    • pp.4216-4222
    • /
    • 2011
  • In this study the inelastic behavior of the existing school buildings with infilled masonry walls is analysed by pushover method. The shear stiffness and strength of masonry wall is calculated from the prior experimets and verified by inelastic analysis. The height of infilled masonry wall affects the structural behavior. The higher the masonry wall height, the higher the initial shear stiffness and strength of masonry wall. As the cracks are developed, the strength of masonry wall is much decreased. The proposed inelastic analysis method shows similar results with the experiments and can be used as inelastic analysis model of reinforced concrete buildings with infilled masonry walls.

In-plane and Out-of-plane Seismic Performances of Masonry Walls Strengthened with Steel-Bar Truss Systems (강봉 트러스 시스템으로 보강된 조적벽체의 면내·외 내진 거동 평가)

  • Hwang, Seung-Hyeon;Yang, Keun-Hyeok;Kim, Sanghee
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.25 no.1
    • /
    • pp.16-24
    • /
    • 2021
  • This experimental study was conducted to evaluate the in-plane and out-of-plane seismic performances of an unreinforced masonry walls (URMs) strengthened with prestressed steel-bar truss systems developed in the present investigation. The truss systems were installed on both faces of the walls. All the wall specimens were subjected to lateral in-plane or out-of-plane cyclic loads at the fixed gravity stress of 0.25 MPa. The seismic performance of the strengthened specimens was compared to that measured in the counterpart URM. When compared with the lateral load-displacement curve of the URM, the strengthened walls exhibited the following improvements: 190% for initial stiffness, 180% for peak strength, 610% for accumulated energy dissipation capacity, and 510% for equivalent damping ratio under the in-plane state; the corresponding improvements under the out-of-plane state were 230% for initial stiffness, 190% for peak strength, 240% for accumulated energy dissipation capacity, and 120% for equivalent damping ratio, respectively. These results indicate that the developed technique is very promising in enhancing the overall seismic performance of URM.

Comparative Study on Seismic Performance of Masonry Wall Strengthened by FRP Sheet or Steel-Bar Truss System (FRP 시트 및 강봉 트러스 시스템으로 보강된 조적벽의 내진성능 비교 연구)

  • Lee, Hye-Ji;Kim, Sanghee;Yang, Keun-Hyeok
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.26 no.5
    • /
    • pp.1-9
    • /
    • 2022
  • In this study, the in-plane and out-of-plane seismic performance of the masonry wall strengthened using the steel bar truss system proposed by Hwang et al. (2021a, 2021b) or using FRP sheets were compared and evaluated. The maximum strength of the masonry wall reinforced with FRP sheets for the in-plane and out-of-plane loading was 71% and 85%, respectively, of that of the non-reinforced masonry wall. Meanwhile, the maximum strength of the masonry wall reinforced with the steel bar truss system was approximately 1.8 times higher than that of the non-reinforced masonry wall. Compared with the FRP sheet method, the steel bar truss system was excellent at improving the maximum load capacity, rigidity, and energy dissipation capacity. However, in the case of a masonry wall reinforced with FRP sheets, the masonry wall was overstrengthened with the FRP sheets covering the entire masonry wall, and it is considered that the overstrengthened specimen experienced sliding failure, resulting in a lower strength than the other specimens. A follow-up study is needed to compare the seismic performance of the specimen involving only a part of the masonry wall reinforced with the FRP sheets and the specimen reinforced using the steel bar truss system.

Proposing the Shear Force Equation of GFRP Strengthened Masonry Wall (유리섬유로 보강한 조적벽체의 전단내력식 설정에 관한 연구)

  • Kwon, Ki-Hyuk;Lee, Soo-Chul;Jung, Won-Chul
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.7 no.1 s.24
    • /
    • pp.1-9
    • /
    • 2007
  • This study does by purpose that propose shear resisting force equation of reinforced masonry wall that is reinforced by GFRP(glass fiber reinforced polymer) based on result that is noted through cyclic loading of masonry wall and a shaking table experiment of mock that reflect identifying marks of masonry building which is constructed in domestic. It was Rocking mode to dominate failure of masonry wall in the experiment results, and the equations of UBC show the most resemblant value with experiment results. Through this study, propose the shear force equation of GFRP strengthened masonry wall as following. $$V_n=0.02A_n{\sqrt{f'_m}}+0.022b_gh_g(1+2{\alpha})^3{\sqrt{f_g}}(N/mm^2)$$.

Nonlinear Analytical Model of Unreinforced Masonry Wall using Fiber and Shear Spring Elements (파이버 및 전단 스프링요소를 이용한 비보강 조적벽체의 비선형 해석모델)

  • Hong, Jeong-Mo;Shin, Dong-Hyeon;Kim, Hyung-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.31 no.6
    • /
    • pp.283-291
    • /
    • 2018
  • This study intends to develop an analytical model of unreinforced masonry(URM) walls for the nonlinear static analysis which has been generally used to evaluate the seismic performance of a building employing URM walls as seismic force-resisting members. The developed model consists of fiber elements used to capture the flexural behavior of an URM wall and a shear spring element implemented to predict its shear response. This paper first explains the configuration of the proposed model and describes how to determine the modeling parameters of fiber and shear spring elements based on the stress-strain curves obtained from existing experimental results of masonry prisms. The proposed model is then verified throughout the comparison of its nonlinear static analysis results with the experimental results of URM walls carried out by other researchers. The proposed model well captures the maximum strength, the initial stiffness, and their resulting load - displacement curves of the URM walls with reasonable resolution. Also, it is demonstrated that the analysis model is capable of predicting the failure modes of the URM walls.

An Experimental Study on the Influence of Masonry InFilled Walls on the Seismic Performance of Reinforced Concrete Frames with Non-seismic Details (정적실험을 통한 조적채움벽체가 비내진상세 RC 골조의 내진성능에 미치는 영향 평가)

  • Kim, Kyoung-Min;Choen, Ju-Hyun;Baek, Eun-Rim;Oh, Sang-Hoon;Hwang, Cheol-Seong
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.21 no.3
    • /
    • pp.114-120
    • /
    • 2017
  • In this paper, the effect of the masonry infill walls on the seismic performance of the reinforced concrete(RC) frames with non-seismic details was evaluated through the static test of an masonry infilled RC frame sub-assemblage with non-seismic details of real size, and comparison with the test results of the RC frame sub-assemblage with non-seismic details. As the test results, lots of cracks occurred on the surface of the entire frame due to the compression of the masonry infilled wall, and the beam-column joint finally collapsed with the expansion of the shear crack and buckling(exposure) of the reinforcement. On the other hand, the stiffness of the shear force-story drift relationship decreased due to the wall sliding crack and column flexural cracks, and the strength finally decreased by around 60% of the maximum strength. The damage that concentrated on the upper and lower parts of columns was dispersed in the entire frame such as columns, a beam, and beam-column joints due to the wall, and the specimen was finally collapsed by expansion of the shear crack of the joint, not the shear crack of the column. Also, the stiffness of RC frame increased by 12.42 times and the yield strength by 3.63 times, while the story drift at maximum strength decreased by 0.18 times.

Seismic Performance Evaluation of Unreinforced and ECC-jacketed Masonry Fences using Shaking Table Test (진동대실험을 사용한 비보강 및 ECC 자켓 보강 조적담장의 내진성능평가)

  • Yonghun Lee;Jinwoo Kim;Jae-Hwan Kim;Tae-Sung Eom;Sang-Hyun Lee
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.27 no.6
    • /
    • pp.182-192
    • /
    • 2023
  • In this study, the efficacy of Engineered Cementitious Composite(ECC) jacket for masonry fences subjected to lateral dynamic load was experimentally verified through a shaking table test, comparing it with the performance of an unreinforced masonry(URM) fence. Firstly, dominant frequencies, modal damping ratios and deformed shapes were identified through an impact hammer test. URM and ECC-strengthened fences with heights of 940mm and 970mm had natural frequencies of 6.4 and 35.3Hz, and first modal damping ratios of 7.0 and 5.3%, respectively. Secondly, a shaking table test was conducted in the out-of-plane direction, applying a historical earthquake, El Centro(1940) scaled from 25 to 300%. For the URM fence, flexural cracking occurred at the interface of brick and mortar joint(i.e., bed joint) at the ground motion scaled to 50%, and out-of-plane overturning failure followed during the subsequent test conducted at the ground motion scaled to 30%. On the other hand, the ECC-jacketed fence showed a robust performance without any crack or damage until the ground motion scaled to 300%. Finally, the base shear forces exerted upon the URM and ECC-jacketed fences by the ground motions scaled to 25~300% were evaluated and compared with the ones calculated according to the design code. In contrast to the collapse risk of the URM fence at the ground motion of 1,000-year return period, the ECC-jacketed fence was estimated to remain safe up to the 4,800-year return period ground motion.

Experimental Investigation of The Shear Strengthening of Unreinforced Masonry Infilled RC Frames Using CFRP Sheet (CFRP Sheet를 이용한 철근콘크리트 프레임면내 조적벽체의 전단내력 평가에 관한 실험적 연구)

  • Lee, Young-Hak;Kim, Min-Sook;Byon, Eun-Hyuk;Kim, Hee-Cheul
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.14 no.1
    • /
    • pp.63-70
    • /
    • 2010
  • The purpose of this study is to investigate experimentally the behavior of unreinforced masonry RC frames strengthened by CFRP sheet under cyclic lateral loading. Four test specimens were constructed as one-story, one-bay, 1/2 scale unreinforced masonry infilled RC frames and differences in strength and stiffness were evaluated in specimens on which had been applied different retrofitting methods. Test results indicated that the CFRP sheets significantly increased the strength and stiffness of the specimens, and the specimens retrofitted in columns and masonry indicated the most adequate retrofitting methods.

Seismic Performance of Reinforced Concrete Frame with Masonry Waist-high Wall using Aramid Fiber (아라미드 섬유를 이용한 철근콘크리트 프레임 면내 조적 허리벽의 내진보강성능)

  • Kim, Hye-Jin;Cho, Seung-Ho;Rho, Kwang-Geun;Lee, Sang-Hyun;Chung, Lan
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.99-100
    • /
    • 2009
  • In this paper, wish to achieve an experimental study to investigate enhanced performance of the masonry walls strengthened in shear and ductility using Aramid fiber strip.

  • PDF