• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.04a
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• pp.44-49
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• 1989

The primary purpose of using bracings is to improve tile lateral rigidity of main structural system, i.e., columns and beams, by reinforcing them with much smaller members. Conventional design methods consider bracings as tension-only mambers, since difficulties arise in the analysis to consider the P - effects and post-buckling behaviour of the bracing members. This is particulary true for X-bracings. Recently, however, both analytical and experimental studies have been conducted to investigate the more precise and real behaviour of bracing members, especially for the nonlinear un plastic behaviour under cyclic loads. In this study, an analytical model is proposed to investigate the nonlinear behavior of steel bracing members subjected to cyclic loads. Results of tile analysis were compared with previous experimental results, and good agreements were obtained between these results.

• Computers and Concrete
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• v.3 no.4
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• pp.261-284
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• 2006

The flexural behaviour of symmetrically reinforced concrete (RC) columns cast of normal- and high-strength concrete under both monotonic and cyclic loading is studied based on an analytical procedure, which employs the actual stress-strain curves and takes into account the stress-path dependence of concrete and steel reinforcement. The analysis is particularly extended into the post-peak stage with large inelastic deformation at various applied axial load level. The effect of axial load on their complete flexural behaviour is then identified based on the results obtained. The axial load is found to have fairly large effect on the flexural behaviour of RC columns under both monotonic and cyclic loading. Such effects are discussed through examination of various aspects including the moment-curvature relationship, moment capacity, flexural ductility, variation of neutral axis depth and steel stress.

• Steel and Composite Structures
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• v.1 no.1
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• pp.33-50
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• 2001

In this paper an experimental study is performed on end-plate type joints. The test arrangement represents a column-base joint of a steel frame. Altogether six specimens were tested, each of them subjected to cyclic loading. The specimens were carefully designed by performing detailed preliminary calculations so that they would present typical behaviour types of end-plate joints. On the basis of the experimentally established moment-rotation relationship, the cyclic characteristics of each specimen have been calculated and compared to one another. The results are evaluated, qualitative and quantitative conclusions are drawn.

• Journal of Welding and Joining
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• v.2 no.1
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• pp.49-57
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• 1984

The influence of weld defect, residual stress and microstructure on the Low Cycle Fatigue(L. C. F.) behaviour of AISI 304L austenitic stainless steel weldment has been studied. The specimens were welded by shielded metal are welding process, post weld heat treated(PWHT) at 900.deg.C for 1.5hrs, and tested under total strain controlled condition at room temperature. The results of the experiment showed that weld defect affected the L.C.F. behaviour of weldment deleteriously compared to the residual stress or microstructure, and it reduced the L.C.F. life about 70-80%. The PWHT exhibited beneficial effect on the L.C.F. behaviour and increased the L.C.F. life about 120%. This enhancement by PWHT was attributed to the removal of residual stress and recovery of weld metal ductility. The cyclic stress flow of as welded specimens showed intermediate cyclic softening, whereas those of heat treated specimens showed continuous cyclic hardening, and this difference was explained in terms of the residual stress removal and dislocation behaviour. Scanning electron microscopy studies of fatigue fracture surface showed that weld defects of large size and near weld surface were detrimental to the L.C.F. behaviour of weldment.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1048-1050
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• 1995

Lead-acid battery is used widely as a power source at a automobile, industrial machines, folk lifts, U.P.S. etc. Lead-acid battery is cheaper than arty other secondary battery, but this battery has many disadvantages such as heavy, low energy density, environment problem etc. In this article, we introduce cyclic voltammetry methods to investigate corrosion behaviour of positive grids of Pb-Ca alleys.

• Structural Engineering and Mechanics
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• v.42 no.3
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• pp.383-407
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• 2012

A numerical approach to simulate the behaviour of timber shear walls under both static and dynamic loading is proposed. Because the behaviour of timber shear walls hinges on the behaviour of the nail connections, the force-displacement behaviour of sheathing-to-framing nail connections are first determined and then used to define the hysteretic properties of finite elements representing these connections. The model nails are subsequently implemented into model walls. The model walls are verified using experimental results for both monotonic and cyclic loading. It is demonstrated that the complex hysteretic behaviour of timber shear walls can be reasonably represented using model shear walls in which nonlinear material failure is concentrated only at the sheathing-to-framing nail connections.

• Steel and Composite Structures
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• v.1 no.3
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• pp.355-376
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• 2001

An experimental research program on end-plate beam-to-column composite joints under cyclic loading is presented. The major focus relates to the identification of the contribution of the concrete confinement in composite columns to the behaviour of the joint, on internal nodes and external nodes, together with an assessment of degradation of strength and stiffness in successive loading cycles. From the experimental results it was possible to identify the various failure modes and to fit the corresponding hysteretic curves to the Richard-Abbott and Mazzolani models. These curve-fitting exercises highlighted the need to adapt both models, either for improved ease of application, or to deal with some aspects previously not covered by those models.

• Structural Engineering and Mechanics
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• v.21 no.4
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• pp.469-494
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• 2005

In order to consider the modified seismic response of framed structures in the presence of masonry infills, proper models have to be formulated. Because of the complexity of the problem, a careful definition of an equivalent diagonal pin-jointed strut, able to represent the horizontal force-interstorey displacement cyclic law of the actual infill, may be a solution. In this connection the present paper, continuing a previous work in which a generalised criterion for the determination of the ideal cross-section of the equivalent strut was formulated, analizes some models known in literature for the prediction of the lateral cyclic behaviour discussing their field of validity. As a support of the discussion, the results of an experimental investigation involving single story-single bay infilled reinforced concrete. Frames under vertical and lateral loads with different kind of infill (actually not yet so much investigated) are presented. Finally, an improvement of a model known in the literature is proposed, taking the results of the experimental tests before mentioned into account.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.295-302
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• 2000

Earthquakes not only produce additional load on the structures and underlying soil, but also change the strength characteristics of the soil. Therefore, in order to analyze soil structures for stability, the behaviour after earthquake must be considered. In this paper, a series of cyclic triaxial tests and monotonic triaxial tests were carried out to investigate the undrained shear strength and liquefaction strength characteristics of Nak-Dong River sand soils which were subjected to cyclic loading. The sample was consolidated in the first stage and then subjected to stress controlled cyclic loading with 0.1Hz. After the cyclic loading, the cyclic-induced excess pore water pressure was dissipated by opening the drainage valve and the sample was reconsolidated to the initial effective mean principal stress(p/sub c/'). After reconsolidation, the monotonic loading or cyclic loading were applied to the specimen. In the results, the undrained shear strength and liquefaction strength characteristics depended on the pore pressure ratio(Ur=U/p/sub c/'). The volume change following reconsolidation can be a function of cyclic-induced excess pore water pressure and the maximum double amplitude of axial strain.

• Computational Structural Engineering
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• v.2 no.3
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• pp.69-75
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• 1989

The primary purpose of using bracings is to improve the lateral rigidity of main structural system, i.e., columns and beams, by reinforciing them with much smaller members. In conventional design methods brackings are considered as tension-only members, since difficulties arise in the analysis when the P-.DELTA. effects and post-buckling behaviour of the bracing members are taken into account. This is particulary true fox X-bracings. Recently, however, both analytical and experimental studies have been conducted to investigate the more precise and real behaviour of bracing members, especially for the nonlinear and plastic behaviour under cyclic loads. In this study, an analytical model is proposed to investigate the nonlinear behavior of steel bracing members subjected to cyclic loads. Results of the analysis were compared with previous experimental results, and good agreements were obtained between these results.