• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.143-147
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• 1992

Description of the behavior of the R.C structural members fixed on massive concrete is not normally generalization of recognized configuration for regular R.C. design guidanes. This can be due to the complexity of evaluation of internal resistancy and deflection changes of the members subjected to the various external forces. On the base of axially loaded member fixed on footing, however, the estimation of deflection changes due to flexural force shear force and rotational force is to be carried out in ways of specifying the bond characteristics of axial bars embedded in massive concrete. This work is to quantify adhesion of steel-concrete, initial concrete cracking stress near bar rib, maximum bond stress and residual stress in concrete respectively. In addition to quantification of them for particulate behavior, the suggestions of multi-linear bond stress-slip diagram made in carrying out finite element analyses for adhesion failure, examining concrete cracking status and reviewing existing experimental data lead to alternatively constructed relationship between bond stress and slip for a axial bars embedded massive concrete.

• Structural Engineering and Mechanics
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• 제24권3호
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• pp.355-374
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• 2006

Thin walled steel bridge-piers/columns are vulnerable to damage, when subjected to earthquake excitations. Local buckling, global buckling or interaction between local and global buckling usually is the cause of this damage, which results in significant strength reduction of the member. In this study new innovative design concepts, "thin-walled corrugated steel columns" and "thin-walled cellular steel columns" are presented, which allow the column to undergo large plastic deformations without significant strength reduction; hence dissipate energy under cyclic loading. It is shown that, compared with the conventional designs, circular and stiffened box sections, these new innovative concepts might results in cost-effective designs, with improved buckling and ductility properties. Using a finite element model, that takes the non-linear material properties into consideration, it is shown that the corrugations will act like longitudinal stiffeners that are supporting each other, thus improving the buckling behavior and allowing for reduction of the overall wall thickness of the column.

• Structural Engineering and Mechanics
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• 제81권2호
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• pp.231-242
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• 2022

Numerical solutions for the linear buckling behavior of thin-walled circular hollow section members (CHS) with and without longitudinal stiffeners are presented using the semi-analytical finite strip method (SAFSM) which is developed based on Marguerre's shallow shell theory and Kirchhoff's assumption. The formulation of 3-nodal line finite strip is presented. The CHS members subjected to uniform axial compression, uniform bending, and combination of compression and bending. The buckling behavior of CHS is investigated through buckling curves which relate buckling stresses to lengths of the member. Effects of longitudinal stiffeners are studied with the change of its dimensions, position, and number.

• 국제초고층학회논문집
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• 제4권1호
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• pp.57-64
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• 2015

Recently, new keywords such as "Resilience" and "Repairability" have been discussed from the perspective of the sustainability of damaged structures after a severe disaster. To evaluate the repairability and recovery of structures, it is necessary to establish an analytical method that can simulate the behavior of repaired structures. Furthermore, it is desirable to establish an evaluation method for the structural performance of repaired structures. This study investigates the repairability and recovery of steel members that are damaged by local buckling or cracks. This paper suggests a simple analytical model for repaired steel members, in order to simulate the inelastic behavior and evaluate the recoverability of the structural performance. There is good agreement between the analytical results and the test results. The proposed analytical method and model can effectively evaluate the recoverability.

• 한국강구조학회 논문집
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• 제17권6호통권79호
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• pp.649-660
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• 2005

강박스거더교 다이아프램의 맨홀은 지금까지 경험적으로 설계하여, 강교제작에 과도한 비용을 유발시키는 한 요인이 되고 있다. 다이아프램 맨홀 제작의 경제성과 효율성을 제고시키기 위해서는 다이아프램 맨홀부의 정확한 거동분석을 통한 검토가 필요하다. 본 논문에서는 강상자형교 지점부의 다이아프램 맨홀의 거동 분석을 위해 현장실측과 구조해석이 수행되었다. 여러 가지 맨홀 형상들에 대한 상세 구조해석을 통하여, 강박스거더교의 지점부 다이아프램 맨홀의 적절한 보강방법에 대하여 제안하였다.

• Journal of the Korean Wood Science and Technology
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• 제42권1호
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• pp.20-26
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• 2014

본 연구에서는 유한요소해석을 이용하여 응력적층 바닥판의 구조성능을 평가하였다. 바닥판의 구조성능은 처짐과 응력, 압체력의 변화로 평가할 수 있다. 하중 재하 후 바닥판의 처짐 형상을 확인한 결과 하나의 판처럼 거동하는 것을 확인하였다. 이는 압체력에 의해 각 부재 사이에 마찰력이 작용했기 때문이다. 또한 초기 압체력과 산출된 압체력을 비교한 결과 바닥판의 처짐과 함께 압체력이 감소했다. 이는 하중에 의해 바닥판의 변형이 발생하면서 작용하는 힘이 줄어듦에 따라 압체력이 감소한 것으로 판단된다. 그러나 재료의 소성 특성이 제대로 반영되지 않았기 때문에 잔류응력과 잔류변형이 고려되지 않았으므로 추후 이에 대한 연구가 필요하다.

• Structural Engineering and Mechanics
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• 제35권1호
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• pp.37-52
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• 2010

Special-shape arch bridge for self-balance (SBSSAB) in Zhongshan City is a kind of new fashioned spatial combined arch bridge composed of inclined steel arch ribs, curved steel box girder and inclined suspenders, and the mechanical behavior of the SBSSAB is particularly complicated. The SBSSAB is aesthetic in appearance, and design of the SBSSAB is artful and particular. In order to roundly investigate the mechanical behavior of the SBSSAB, 3-D finite element models for spatial member and shell were established to analyze the mechanical properties of the SBSSAB using ANSYS. Finite element analyses were conducted under several main loading cases, moreover deformation and strain values for control section of the SBSSAB under several main loading cases were proposed. To ensure the safety and rationality for optimal design of the SBSSAB and also to verify the reliability of its design and calculation theories, the 1/10 scale model tests were carried out. The measured results include the load checking calculation, lane loading and crowd load, and dead load. A good agreement is achieved between the experimental and analytical results. Both experimental and analytical results have shown that the SBSSAB is in the elastic state under the planned test loads, which indicates that the SBSSAB has an adequate load-capacity. The calibrated finite-element model that reflects the as-built conditions can be used as a baseline for health monitoring and future maintenance of the SBSSAB.

• 한국구조물진단유지관리공학회 논문집
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• 제7권2호
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• pp.247-261
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• 2003

The technique of posttensioning has been used successfully to improve the performance of existing concrete structures. However, very few applications of this technique can be found in steel structures. Posttensioning by means of high strength cable or bar can be used to effectively increase the working load capacity of Truss Bridges. The benefits of posttensioning trusses can be achieved in strengthening of existing structures as well as in the design of new structures. In this paper, the elastic behavior of posttensioned trusses with straight and draped tendon profiles is examined. For the analysis of posttensioned trusses in the elastic range of behavior, two methods are presented, namely, the flexibility method and the mixed-method, i.e., a combination of the stiffness and flexibility methods. Using the presented methods, the effects of design variables such as the tendon profile, truss type, prestress force, and tendon eccentricity on the working load and deflection of trusses are studied. The results show that the allowable load of truss increases proportionally with increase in prestress force and eccentricity. Posttesioning enlarges the elastic range, increases redundancy, and reduces deflection and member stresses. Thus, the remaining life of a truss bridge can be increased relatively inexpensively.

• 한국구조물진단유지관리공학회 논문집
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• 제8권4호
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• pp.231-238
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• 2004

본 논문은 스터드를 사용한 철근콘크리트 부재와 철골 부재의 접합부의 인장거동에 관한 연구를 나타내었다. 스터드 접합부의 인장 및 휨 성능을 향상시키기 위하여 행거를 스터드 주위에 설치하였다. 행거로 보강된 스터드 접합부의 인장 성능을 평가하기 위하여 철근비, 행거 상세, 묻힘길이 등을 변수로 한 8 개의 실험체를 계획하였다. 인장실험을 통하여 행거 보강이 접합부의 인장강도를 증가시키는데 매우 효과적인 것을 알 수 있었다. 기준식에 의한 인장강도 평가로부터 CCD식이 강도 산정에 보다 적합한 것으로 나타났다.

• Structural Engineering and Mechanics
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• 제62권4호
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• pp.417-430
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• 2017

Ultra high performance concrete (UHPC) has aroused interest around the world owing to superior mechanical and durability properties over conventional concrete. However, the application of UHPC in practice poses difficulties due to its inherent brittleness. UHPC filled in steel tube columns (UHPC-FSTCs) are capable of restricting the brittle failure of non-reinforced UHPC columns and forming a high performance member with enhancement of strength and ductility. Currently, research on UHPC-FSTCs remains very limited and there is relatively little information about the mechanical behavior of these columns. Therefore, this study presents a review of past experimental studies to have a deeper insight into the compressive behavior of UHPC-FSTCs under axial loading on entire section and on concrete core. Based on the test results obtained from Schneider (2006) and Xiong (2012), an analysis was conducted to investigate the influence of the confinement index (${\xi}$) and diameter to steel tube thickness ratio (D/t) on the strength and the ductility in short circular UHPC-FSTCs. Furthermore, the appropriateness of current design codes including EC4, AISC, AIJ and previous analytical models for estimating the ultimate loads of composite columns was also examined by the comparison between the predictions and the test results. Finally, simplified formulae for predicting the ultimate loads in two types of loading pattern were proposed and verified.