• Title/Summary/Keyword: deformation behaviour

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Modeling of coupled THMC processes in porous media

  • Kowalsky, Ursula;Bente, Sonja;Dinkler, Dieter
    • Coupled systems mechanics
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    • v.3 no.1
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    • pp.27-52
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    • 2014
  • For landfill monitoring and aftercare, long-term prognoses of emission and deformation behaviour are required. Landfills may be considered as heterogeneous porous soil-like structures, in which flow and transport processes of gases and liquids interact with local material degradation and mechanical deformation of the solid skeleton. Therefore, in the framework of continuous porous media mechanics a model is developed that permits the investigation of coupled mechanical, hydraulical and biochemical processes in municipal solid waste landfills.

Behaviour factor and displacement estimation of low-ductility precast wall system under seismic actions

  • Tiong, Patrick L.Y.;Adnan, Azlan;Hamid, Nor H.A.
    • Earthquakes and Structures
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    • v.5 no.6
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    • pp.625-655
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    • 2013
  • This paper investigated the seismic behaviour of an innovated non-ductile precast concrete wall structural system; namely HC Precast System (HCPS). The system comprises load-bearing precast wall panels merely connected only to column at both ends. Such study is needed because there is limited research information available in design codes for such structure particularly in regions having low to moderate seismicity threats. Experimentally calibrated numerical model of the wall system was used to carry out nonlinear pushover analyses with various types of lateral loading patterns. Effects of laterally applied single point load (SPL), uniformly distributed load (UDL), modal distributed load (MDL) and triangular distributed load (TDL) onto global behaviour of HCPS were identified. Discussion was focused on structural performance such as ductility, deformability, and effective stiffness of the wall system. Thus, a new method for engineers to estimate the nonlinear deformation of HCPS through linear analysis was proposed.

Flexural behaviour of reinforced concrete beams strengthened with NSM CFRP prestressed prisms

  • Liang, Jiong-Feng;Yu, Deng;Xie, Shengjun;Li, Jianping
    • Structural Engineering and Mechanics
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    • v.62 no.3
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    • pp.291-295
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    • 2017
  • The behaviour of reinforced concrete beams strengthened with near surface mounted (NSM) CFRP prestressed prisms was experimentally investigated. Five RC beams were tested under four point bending. All beams were made with dimensions of 300 mm in width, 2000 mm in length and 150 in depth. The effects of presstress level of CFRP prestressed prisms and prism material type were studied. The failure mode, load capacity, deflection, CFRP strain, steel strain and ductility of the tested beams were all analyzed. The results showed that the behavior of the reinforced concrete beams strengthened with NSM CFRP prestressed prisms showed a significant increase in the load-carrying capacity and the deformation capacity. The NSM CFRP prestressed prisms strengthening technique could be considered as an effective method for repairing RC structures.

The Effect of Strain Rate on Macroscopic Behaviour in Compression Forming of Semi-Solid Aluminum Alloy (반용융 알루미늄 재료의 압축성형시 변형율속도가 미시적 거동에 미치는 영향)

  • 강충길;김기훈
    • Transactions of Materials Processing
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    • v.6 no.4
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    • pp.338-345
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    • 1997
  • The behaviour of alloys in the semi-solid state strongly depends on the imposed stress stage and on the morphology of the phase which can vary from dendritic to globular. To optimal net shape forging of semi-solid materials, it is important to investigate for material behaviour for variation of strain rate. Therefore, to investigate the effect of compression speed on deformation of aluminum alloy with globular microstructure, the compression test for semi-solid aluminum alloy with controlled solid fraction is perform by material test system which is attracted with furance. The behavior of semi-solid aluminum alloy were discussed for the various solid fraction and die speed. The material constants in stress-strain were are also proposed.

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Investigations about the Fracture behaviour on High-Temperature Brazed NiCr20TiAl/BNi-5 Joints (고온 Brazed Joint 파괴 거동에 대한 연구)

  • Steffens, H.D.;Bae, S.C.;Wielage, B.;Dammer, R.
    • Journal of Welding and Joining
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    • v.2 no.1
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    • pp.18-24
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    • 1984
  • With the use of a new method the deformation mechanism of high-temperature-brazed joints can be obtained in a very short time. For that purpose a SEM(Scanning Electron Microscope) was equipped with a high temperature tensile testing machine. By means of SEM-investigation the damage behaviour of high-temperature-brazed joints is exa mined at elevated temperature. Based on these it is possible to make a qualification of the influence over single parts on the damage beginning and behaviour in dependence of temperature. This shall be shown exemplarily for the high temperature material NiCr20TiAl (Nimonic 80A).

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Flexural and shear behaviour of profiled double skin composite elements

  • Anwar Hossain, K.M.;Wright, H.D.
    • Steel and Composite Structures
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    • v.4 no.2
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    • pp.113-132
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    • 2004
  • Double skin composite element (DSCE) is a novel form of construction comprising two skins of profiled steel sheeting with an infill of concrete. DSCEs are thought to be applicable as shear or core walls in a building where they can resist in-plane loads. In this paper, the behaviour of DSCE subjected to combined bending and shear deformation is described. Small-scale model tests on DSCEs manufactured from micro-concrete and very thin sheeting were conducted to investigate the flexural and shear behaviour along with analytical analysis. The model tests provided information on the strength, stiffness, strain conditions and failure modes of DSCEs. Detailed development of analytical models for strength and stiffness and their performance validation by model tests are presented.

Stress-assisted oxidation behaviour of inconel 52M/316 austenitic stainless-steel dissimilar weld joints in a simulated pressurised water reactor

  • Xu, Youwei;Yang, Binhui;Shi, Yu
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3778-3787
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    • 2022
  • The stress-assisted oxidation behaviour of Inconel 52 M/316 austenitic stainless-steel (SS) dissimilar weld joints (DMWJ) in a simulated pressurised water reactor environment was investigated. A corrosion galvanic couple formed between the Inconel 52 M and 316 SS due to differences in their nonferrous metal content. The electric field from the corrosion couple attracted metal cations (e.g. Fe2+, Cr3+) to the Inconel 52 M that were deposited as FeCr2O4. An additional corrosion galvanic couple was generated due to variations in the plastic deformation of the DMWJ. The superposition of electric fields from the different couples resulted in ridge-like oxide depositions in the fusion zone.

Large deformation analysis of inflated air-spring shell made of rubber-textile cord composite

  • Tran, Huu Nam;Tran, Ich Thinh
    • Structural Engineering and Mechanics
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    • v.24 no.1
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    • pp.31-50
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    • 2006
  • This paper deals with the mechanical behaviour of the thin-walled cylindrical air-spring shell (CAS) made of rubber-textile cord composite (RCC) subjected to different types of loading. An orthotropic hyperelastic constitutive model is presented which can be applied to numerical simulation for the response of biological soft tissue and of the nonlinear anisotropic hyperelastic material of the CAS used in vibroisolation of driver's seat. The parameters of strain energy function of the constitutive model are fitted to the experimental results by the nonlinear least squares method. The deformation of the inflated CAS is calculated by solving the system of five first-order ordinary differential equations with the material constitutive law and proper boundary conditions. Nonlinear hyperelastic constitutive equations of orthotropic composite material are incorporated into the finite strain analysis by finite element method (FEM). The results for the deformation analysis of the inflated CAS made of RCC are given. Numerical results of principal stretches and deformed profiles of the inflated CAS obtained by numerical deformation analysis are compared with experimental ones.

Evaluation of Hot Workability for $SiC_P$/Al16061 Composites by Deformation Efficiency (변형효율을 이용한 $SiC_P$/A16061 복합재료의 열간가공성 평가)

  • 고병철
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.03b
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    • pp.176-179
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    • 1999
  • The high temperature deformation behaviour of 15vol% SiCp/A16061 composites has been studied in the temperature range of 300-50$0^{\circ}C$ and the strain rate range of 0.1-3.0/sec by torsion test. On he basis of the flow stress data the strain rate sensitivity(m) of the material is evaluated and used for calculating the deformation efficiency(η) [η=2m/(m+1)] A domain of dynamic recrystallization(DRX) could be identified in these maps by using the deformation efficiency. The characteristicvs of these results has been investigated with the help of determining the region of optimum hot working condition.

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Effect of Static Softening on Hot Plastic Deformation Behaviour for 304Stainless Steel (304 스테인레스강의 고온소성변형특성에 미치는 정적연화 효과)

  • 조상현;김유승;유연철
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.10a
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    • pp.185-188
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    • 1997
  • Static restoration during hot interrupted deformation of 304 stainless steel was studied in the temperature range from 900 to 1100$^{\circ}C$ under various strain rate of 0.05∼ 5/sec and pass strain of 1/4∼3 times peak strain. The static restoration was dependent on the pass strain, deformation temperature and strain rate. Fractional softening(FS) values increased with increasing strain rate, deformation temperature and pass strain. Recystallization kinetics was well explained by the Avrami equation and the time for 50% recrystallization was evaluated using equation of t0.5=2.01${\times}$10-10$\varepsilon$-.156$\varepsilon$ -0.81Dexp(196.66/RT)

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