• 대한기계학회논문집A
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• 제32권12호
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• pp.1153-1160
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• 2008

In this paper, the algorithm of Abaqus UMAT is introduced to analyze the shape memory alloy. The SMA has two main effects which show non-linearity. Due to this, it is hard to analyze SMA using analysis tools and to describe all of two effects. Therefore, in this study, the program using Abaqus UMAT based on Modified Brinson model is used to analyze SMA. The martensite fraction, the most important factor which defines SMA motion, is also calculated by Fortran program in UMAT. In addition, the tensile test of SMA specimen is conducted. The availability of algorithm is proved by comparing analysis to experimental result.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.376-376
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• 2001

• 복합신소재구조학회지
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• 제6권3호
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• pp.17-23
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• 2015

• 국제강구조저널
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• 제18권5호
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• pp.1560-1576
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• 2018

With the aim to provide an efficient platform for the elastic-plastic analysis of steel structures, reinforced concrete (RC) structures and steel-concrete composite structures, a program iFiberLUT based on the fiber model was developed within the framework of ABAQUS. This program contains an ABAQUS Fiber Generator which can automatically divide the beam and column cross sections into fiber sections, and a material library which includes several concrete and steel uniaxial material models. The range of applications of iFiberLUT is introduced and its feasibility is verified through previously reported test data of individual structural members as well as planar steel frames, RC frames and composite frames subjected to various loadings. The simulation results indicate that the developed program is able to achieve high calculation accuracy and favorable convergence within a wide range of applications.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.145-152
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• 2003

This paper develops a relatively comprehensive and sophisticated constitutive model of concrete for finite element analysis of concrete structures. The present model accounts for the hydrostatic pressure sensitivity and Lode angle dependence behavior of concrete, not only in its strength criterion, but also in its hardening characteristics. The implementation is carried out through incorporating the developed concrete model in User Subroutine Material(UMAT) of the general-purpose FE program ABAQUS(v.5.8). It is found that the model can sufficiently predict the hardening as well as the softening behaviour of concrete under high confining pressure.

• 한국전산구조공학회논문집
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• 제23권6호
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• pp.635-640
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• 2010

When using finite element pogram ABAQUS to compute material characteristics, one builds a user material subroutine if unique constitutive feature needs to be included. In ABAQUS/Standard, UMAT subroutine should be built, and in ABAQUS/Explicit, VUMAT should be used. Although two subroutines carry out the same type of task, two different programs should be made depending on the working environment, and it is not easy to program the subroutines following the manual without enough understanding of solid mechanics. In this paper, difference between UMAT and VUMAT subroutines is epitomized, and a conversion scheme from UMAT to VUMAT is discussed. An example shows that the two programs give the same stress computation result.

• Steel and Composite Structures
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• 제23권6호
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• pp.715-726
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• 2017

The paper presents a numerical analysis of a steel-soil composite (SSC) culvert in the scope of static (dead and live) loads. The Abaqus program based on the finite element method (FEM) was used for calculations. Maximum displacements were obtained in the shell crown, and the largest stresses in the haunches. Calculation results were compared with the experimental ones and previous calculations obtained from the Autodesk Robot Structural Analysis (ARSA) program. The shapes of calculated displacements and stresses are similar to those obtained with the experiment, but the absolute values were generally higher than measured ones. The relative differences of calculated and measured values were in the range of 5-23% for displacements, and 15-42% for stresses. Developed calculation model of the SSC culvert in the Abaqus program allows obtaining reasonable values of internal forces in the culvert. Using both calculation programs, the relative differences for displacements were in the range of 15-39%, and 17-44% for stresses in favour of the Abaqus program. Three design methods (Sundquist-Pettersson, Duncan and CHBDC) were used to calculate the axial thrusts and bending moments. Obtained values were compared with test results. Generally, the design methods have conservative assumptions, especially in the live loads distribution, safety factors and consideration the interaction between soil and steel structure.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.577-584
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• 2003

Tension tests of half-thickness concrete containment wall elements and material tests were conducted to derive a crack pattern and constitutive law of concrete. Main test variables are reinforcement ratio and the applied load ratio in two direction, and its effect on the behavior of reinforced concrete panel subjected to biaxial tension is investigated. Based on the test results, analytical expression is derived for the stress-strain relationship of concrete in tension. Ultimate analyses of reinforced concrete panels are carried out by a general purpose structural analysis computer program(ABAQUS), and its results are compared with the test results. The present analysis focuses on the effects of pre-analysis prior to test of specimens. These ultimate tensile analyses as pre-analysis are essential and important to design an effectual scheme of test.

• 한국공간구조학회논문집
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• 제4권1호
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• pp.77-86
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• 2004

시공시 콘크리트의 하중은 받는 데크플레이트의 지지능력은 압축부분 플랜지에서 좌굴에 의해서 결정되어 진다. 얇은 철판 데크플레이트의 압축플랜지에서 중간스티프너의 크기와 위치는 플랜지의 좌굴모드에 강한 영향을 발휘한다. 높은 강도 철판으로 구성된 시험체 단면은 다양한 좌굴모드를 유도하기 위하여 작은 것에서 큰 스티프너에 걸쳐 압축플랜지에 만들어 졌다. ABAQUS 프로그램 해석은 좌굴모드를 지배하는 중간스티프너의 효과를 결정하기 위하여 수행되었다. 각 실험체 시리즈는 단순보로 순수휨이 적용되었다. 실험결과 소성파괴 메카니즘을 통하여 극한파괴에 앞서 다양한 좌굴형상이 나타났다. 실험으로 결정되어진 좌굴응력은 ABAQUS해석으로 얻어진 해석결과와 각국의 규준값들과 비교하기 위하여 사용되었다.

• 한국도로학회논문집
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• 제10권2호
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• pp.167-181
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• 2008

한국형 포장 콘크리트에 있어 구조해석은 다양한 입력변수와 공용성 모형을 연결해주는 중간 매개체 역할을 하고 있어 그 중 요도가 매우 크다. 본 연구에서는 ABAQUS 구조해석 프로그램을 Shell 요소를 이용하여 콘크리트 포장의 거동을 분석할 수 있는 구조해석 기본 모형을 구축하였다. 이 모형을 Closed-Form Solution과 정확성이 검증된 Everfe 프로그램, 그리고 Solid 요소 모형과 비교하여 정확도를 검증하였다. 기본 Shell 모형을 이용하여 다양한 변수에 대한 구조해석을 수행하였으며 그 결과를 DB화하였다. SPSS 통계 프로그램과 해석 결과를 바탕으로 회귀식을 개발하였으며 온도 응력, 상향 응력, 하향 응력을 산정할 수 있는 응력식을 제안하였다.