• Title/Summary/Keyword: lateral-force resistance

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The characteristics of buckling of the CWR with respect to the ballast behaviour (도상 저항력 거동을 고려한 장대레일의 좌굴 특성)

  • Kim Hyun-June;Lee Bang-Woo;Sim Hyun-Woo
    • Proceedings of the KSR Conference
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    • 2003.05a
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    • pp.82-90
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    • 2003
  • The advance in technology of the CWR in Korea has led the establishment of the CWR on the sharp curve (i.e. less than R=600m). As thermit welding used in the sharp-curved construction site is carried out on the curve track, it is difficult to adjust a curve shape accurately and these difficulties have occurred in a number of cases. Therefore, in this study, the lateral buckling analysis of CWR track was carried out considering the actual ballast resistance force. In addition, the cant and vertical resistance force in ballast was considered in order to predict the initial behaviour of bucking in track under the more accurate method.

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A Case Study on the Application of EPS Construction Method Considering Abutment Displacement in Soft Ground (연약지반에서의 교대변위를 고려한 EPS공법의 적용사례 연구)

  • Kang, Hee-June;Oh, Ill-Rok;Chae, Young-Su
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.698-705
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    • 2004
  • Application of structural load on soft ground can cause lateral movement as well as ground break due to pressing and shearing of ground. Especially, abutment supported by pile foundation can make pile deformed due to lateral movement of ground in order to have harmful effect on structure. According to the result of this study, it is required to consider disturbance of weak soil layer when using lateral movement countermeasure method by EPS construction method as a result of performing study on safety review and EPS construction method with respect to this based on site where lateral movement occurs due to backside soil filling load at bridge abutment installed on weak ground, and it is required to sufficiently consider soil reduction during design of EPS construction method due to lateral movement deformation of soft clay layer by losing ground horizontal resistance force due to plasticity of ground around pile as well as combination part damage with pile head and expansion foundation.

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Distortional buckling of I-steel concrete composite beams in negative moment area

  • Zhou, Wangbao;Li, Shujin;Huang, Zhi;Jiang, Lizhong
    • Steel and Composite Structures
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    • v.20 no.1
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    • pp.57-70
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    • 2016
  • The predominant type of buckling that I-steel concrete composite beams experience in the negative moment area is distortional buckling. The key factors that affect distortional buckling are the torsional and lateral restraints by the bottom flange. This study thoroughly investigates the equivalent lateral and torsional restraint stiffnesses of the bottom flange of an I-steel concrete composite beam under negative moments. The results show a coupling effect between the applied forces and the lateral and torsional restraint stiffnesses of the bottom flange. A formula is proposed to calculate the critical buckling stress of the I-steel concrete composite beams under negative moments by considering the lateral and torsional restraint stiffnesses of the bottom flange. The proposed method is shown to better predict the critical bending moment of the I-steel composite beams. This article introduces an improved method to calculate the elastic foundation beams, which takes into account the lateral and torsional restraint stiffnesses of the bottom flange and considers the coupling effect between them. The results show a close match in results from the calculation method proposed in this paper and the ANSYS finite element method, which validates the proposed calculation method. The proposed calculation method provides a theoretical basis for further research on distortional buckling and the ultimate resistance of I-steel concrete composite beams under a variable axial force.

Experimental study on component performance in steel plate shear wall with self-centering braces

  • Liu, Jia-Lin;Xu, Long-He;Li, Zhong-Xian
    • Steel and Composite Structures
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    • v.37 no.3
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    • pp.341-351
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    • 2020
  • Steel plate shear wall with self-centering energy dissipation braces (SPSW-SCEDB) is a lateral force-resisting system that exhibits flag-shaped hysteretic responses, which consists of two pre-pressed spring self-centering energy dissipation (PS-SCED) braces and a wall plate connected to horizontal boundary elements only. The present study conducted a series of cyclic tests to study the hysteretic performances of braces in SPSW-SCEDB and the effects of braces on the overall hysteretic characteristics of this system. The SPSW-SCEDB with PS-SCED braces only exhibits excellent self-centering capability and the energy loss caused by the large inclination angle of PS-SCED braces can be compensated by appropriately increasing the friction force. Under the combined effect of the two components, the SPSW-SCEDB exhibits a flag-shaped hysteretic response with large lateral resistance, good energy dissipation and self-centering capabilities. In addition, the wall plate is the primary energy dissipation component and the PS-SCED braces provide supplementary energy dissipation for system. The PS-SCED braces can provide up to 90% self-centering capability for the SPSW-SCEDB system. The compressive bearing capacity of the wall plate should be smaller than the horizontal remaining restoring force of the braces to achieve better self-centering effect of the system.

Overturning Resistance of Plain Concrete Piers in OSPG Railroad Bridges

  • Rhee, In-Kyu;Park, Joo-Nam;Choi, Eun-Soo
    • International Journal of Railway
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    • v.3 no.1
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    • pp.1-6
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    • 2010
  • The steel plate-girder bridges with concrete gravity piers have possibilities of overturning by lateral inertial force which can be reproduced by sudden earthquake attack. This paper explores an overturning mechanism of existing concrete gravity pier onto the sandy soil in the event of lateral push-over load by in-situ experimental observation. The in-situ push-over experiment for pier with earth anchors between spread footing and rock beds exhibits a reasonable enhancement of ductility against overturning. In unanchored system, a flexural crack at cold joint of concrete pier is not developed because of the over-turning of the pier. This leads a global instability (rotation) of pier-footing system with relatively low stresses in pier itself. While a lateral load is persistently increased in anchored system, the successive flexural cracking failure at cold joint is observed even after the local shear failure of soil due to redistribution of stress equilibrium between soil and pier structure as long as a tensile action of anchor cable is active.

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Seismic Performance of Low-rise Piloti RC Buildings with Concentric Core (중심코어를 가지는 저층 철근콘크리트 필로티 건물의 내진성능)

  • Yoon, Tae-Ho
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.4_2
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    • pp.611-619
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    • 2022
  • In this study, the seismic performance of low - rise piloti buildings with concentric core (shear wall) position is analysed and reviewed based on KDS 41. The prototype is selected among the constructed low - rise piloti buildings with concentric core designed based on KBC 2005 which was used for many low - rise piloti buildings construction. The seismic performance of the building shows plastic behavior in X-direction and elastic behavior in Y-direction. The inter-story drift is lager than that of concentric core case and is under the maximum allowed drift ratio. The displacement ratio of first story is much lager the that of upper stories, and the frame structure in the first story is evaluated as vulnerable to lateral force. Therefore, low - rise piloti buildings with concentric core need the diminishment of lateral displacement and reinforcement of lateral resistance capacity in seismic design and seismic retrofit.

Experimental Study on the Shear Behavior of Ultra High Performance Precast PSC Bridge Joint with Joint Type and Lateral Force (접합 조건 및 횡구속 조건에 따른 초고성능 프리캐스트 PSC 교량 접합부의 전단 거동에 관한 실험적 연구)

  • Lee, Chang-Hong;Kim, Young-Jin;Chin, Won-Jong;Choi, Eun-Suk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.5A
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    • pp.379-387
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    • 2011
  • According to the development of ultra-high performance concrete (UHPC), its mechanical performance have been known as superior than normal and/or high performance concrete. However, its construction and structural safety must have studied with revisions and supplements. In this study, tests have been performed on UHPC precast segment joint with different levels of joint types and lateral forces under direct shear. From the results of the experimental tests, it can be concluded that the properties of the referred joints are significant for the resistance of shear behavior, and the increase of lateral force in these joints may suggest as critical lateral stress on that behavior.

On the member reliability of wind force-resisting steel frames designed by EN and ASCE rules of load combinations

  • Kudzys, Antanas;Kudzys, Algirdas
    • Wind and Structures
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    • v.12 no.5
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    • pp.425-439
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    • 2009
  • The expediency of revising universal rules for the combination of gravity and lateral actions of wind force-resisting steel structures recommended by the Standards EN 1990 and ASCE/SEI 7-05 is discussed. Extreme wind forces, gravity actions and their combinations for the limit state design of structures are considered. The effect of statistical uncertainties of extreme wind pressure and steel yield strength on the structural safety of beam-column joints of wind force-resisting multistory steel frames designed by the partial factor design (PFD) and the load and resistance factor design (LRFD) methods is demonstrated. The limit state criterion and the performance process of steel frame joints are presented and considered. Their long-term survival probability analysis is based on the unsophisticated method of transformed conditional probabilities. A numerical example illustrates some discrepancies in international design standards and the necessity to revise the rule of universal combinations of loads in wind and structural engineering.

종이의 단축압축 표준시험법 개발

  • Kim, Hyoung-Jin;Um, Gi-Jeung;Lee, Tai-Ju;Ko, Seung-Tae;Yoo, Yeong-Jeong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2007.11a
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    • pp.325-330
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    • 2007
  • Uniaxial tensile test are generally much simpler than uniaxial compressive test. Uniaxial compressive test is experimentally more difficult because of the low buckling resistance of a sheet of paper. In order to avoid buckling, many researchers have applied various lateral restraint techniques to investigate paper uniaxial compression behavior. Adding unnecessary force to inhibit compressive deformation of the sheet is unwanted, but sufficient force must be used to inhibit buckling. This study has been carried out to develop new uniaxial compressive standard test method without exerting unnecessary force to paper specimen to prevent buckling.

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Shear Characteristics of RC Short Column Strengthened with Steel Fiber (강섬유로 보강된 RC 단주의 전단특성)

  • 장극관;이현호;양승호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.157-162
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    • 2001
  • The purpose of this study is to investigate the enhancement of shear capacity according to steel fiber contents in RC short columns. Lateral force resistance test was performed with the parameters of steel fiber contents in concrete volume. From the test results, shear and ductility capacity was improved with steel fiber contents Increased. In addition, an optimal steel fiber content was evaluated as a 1.5 % of concrete volume.

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