• Structural Engineering and Mechanics
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• v.46 no.5
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• pp.695-711
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• 2013

It is reasonable to assume that reinforced concrete (RC) structures enter the nonlinear range of response during a severe ground motion. Numerical analysis to predict the behaviour therefore must allow for the presence of nonlinear deformations if an accurate estimate of seismic response is aimed. Among the factors contributing to inelastic deformations, the influence of the degradation of the bond slip phenomenon is important. Any rebar slip generates an additional rotation at the end regions of structural members which are not accounted for in a conventional analysis. Although these deformations could affect the seismic response of RC structures considerably, they are often neglected due to the unavailability of suitable models. In this paper, the seismic response of two types of RC structures, designed according to the Iranian concrete code (ABA) and the Iranian seismic code (2800), are evaluated using nonlinear dynamic and static analyses. The investigation is performed using nonlinear dynamic and static pushover analysis considering the deformations due to anchorage slip. The nonlinear analysis results confirm that bond slip significantly influences the seismic behavior of RC structure leading to an increase of lateral deformations by up to 30% depending on the height of building. The outcomes also identify important parameters affecting the extent of this influence.

• Earthquakes and Structures
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• v.11 no.1
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• pp.141-163
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• 2016

Fiber models have been developed and applied to various structural elements such as shear walls, beams and columns. Only scarcely have fiber models been applied to circular foundation systems such as cast in drilled holes shafts (CIDH). In pile foundations with constraint head boundary conditions, shear deformations can easily contribute to the lateral pile response. However, soil structure interaction formulations such as the p-y method, commonly used for lateral pile design, do not include structural shear deformations in its traditional derivation method. A fiber model that couples shear and axial-bending behavior, originally developed for wall elements was modified and validated on circular cross sections (columns) before being applied to a 0.61 m diameter reinforced concrete (RC) pile with fixed head boundary conditions. The analytical response was compared to measured test results of a fixed head test pile to investigate the possible impact of pile shear deformations on the displacement, shear, and moment profiles of the pile. Results showed that shear displacements and forces are not negligible and suggest that nonlinear shear deformations for RC piles should be considered for fixed-head or similar conditions. Appropriate sensor layout is recommended to capture shear deformation when deriving p-y curves from field measurements.

• The Transactions of the Korea Information Processing Society
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• v.4 no.3
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• pp.792-801
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• 1997

In this paper we propose an algorithm which fits a surface to noise-corrupted data points using an aceive sur-vace with global deformations.It is 3-dimensional surface extension of our precious works on 2-dimensional curve modell[11,12].We use fimite differences,and represent shapes of surface as global transfromation suring evolution based on the ballon [odel[2,3]which allows partial inflation or deflation by using niegborhood'sextermal foreces on each node points.At first,we make local deformations based on the balloon [odel,and then the blobal transformation from the surface before deformations to the defomed surface is calcualted by the deterministic lest squre method,finally we apply the global transformation to the surface before deformations.In experiments we fit a surface(elliposid,B-spline)to noise-corrupted 3D data points using the active surface with affine deformations.

• Structural Engineering and Mechanics
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• v.42 no.4
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• pp.589-608
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• 2012

In this study, the effect of in-plane deformations on the dynamic behavior of laminated plates is investigated. For this purpose, the displacement-time and strain-time histories obtained from the large deflection analysis of laminated plates are compared for the cases with and without including in-plane deformations. For the first one, in-plane stiffness and inertia effects are considered when formulating the dynamic response of the laminated composite plate subjected to the blast loading. Then, the problem is solved without considering the in-plane deformations. The geometric nonlinearity effects are taken into account by using the von Karman large deflection theory of thin plates and transverse shear stresses are ignored for both cases. The equations of motion for the plate are derived by the use of the virtual work principle. Approximate solution functions are assumed for the space domain and substituted into the equations of motion. Then, the Galerkin method is used to obtain the nonlinear algebraic differential equations in the time domain. The effects of the magnitude of the blast load, the thickness of the plate and boundary conditions on the in-plane deformations are investigated.

• Journal of Korean Society of Steel Construction
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• v.10 no.1 s.34
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• pp.11-24
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• 1998

The composite sandwich plate is constructed by combining two laminated facings with high strength and a thick core of light weight material. The governing equations for the analysis of bending of simply supported sandwich plates with laminated facings are derived and analysed using the analytical method including the local shear deformations. The accuracy of the approach is ascertained by comparing solutions from the sandwich plate theory with composite facings to the laminate plate theory. Since the present analysis considers the bending stiffness of the core and also the transverse shear deformations of the laminated facings, it is expected that the analysis is capable to analyze the general anisotropic laminated plates with global shear deformations.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.429-432
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• 1999

The concrete slab on the foundation may have curling and warping deformations due to moisture and temperature gradient of its section. These deformations may change the support conditions of concrete slabs, and cause higher level of stresses than expected. This study was performed to verify the effect of partial support condition of concrete slab on the foundation due to its deformations and to develop the useful analytic method for describing these phenomenons. The partial support condition verified by FWD test results, and it was concluded that the gap model could be useful in analysing the concrete slab with partial support conditions.

• Journal of the Korean Mathematical Society
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• v.39 no.1
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• pp.91-102
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• 2002

Let M and N be CR manifolds with nondegenerate Levi forms of hypersurface type of dimension 2m ＋ 1 and 2n ＋ 1, respectively, where 1 $\leq$ m $\leq$ n. Let f : M longrightarrow N be a CR mapping. Under a generic assumption we construct a complete system of finite order for the infinitesimal deformations of f. In particular, we prove the space of infinitesimal deformations of f forms a finite dimensional Lie algebra.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.178-184
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• 1995

A new combined isotropic/kinematic and orthotropic hardening viscoplastic model is proposed which can account for not only differential orientations but also preferred orientations of grains in n metal at finite plastic deformations with an introduction of multiple spin (rate of rotation) concept within the general framework of the model, the effects of anisotropy and constitutive spins will be discussed in conjunction with a closed-form solution for simple shear in n rigid-plastic material, which will be used to simulate experimental data of Montheillet, et al. (1984) for fixed-end tortion tests at finite plastic deformations.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.03a
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• pp.47-51
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• 1996

Unsteady-state temperature distributions and thermal deformations of a spindle system are studied in this paper. Three dimensional model is built for analysis, and the amount of heat generation of bearing and the thermal characteristic values including heat transfer coefficient are estimated. Temperature distributions and thermal deformations of a model are analyzed using the finite element method and the termal boundary values. Numerical results are compared with the measured data. The results show that thermal deformations and temperature distributions of a high precision spindle system can be reasonably estimated using the three dimensional model and the finite element method.

• Journal of the Korean Mathematical Society
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• v.56 no.6
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• pp.1655-1687
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• 2019

In this paper we define a new type of cohomology for multiplicative Hom-associative algebras, which generalizes Hom-type Hochschild cohomology and fits with deformations of Hom-associative algebras including the deformation of the structure map ${\alpha}$. Moreover, we provide various observations and similarly a new type cohomology of Hom-bialgebras extending the Gerstenhaber-Schack cohomology for Hom-bialgebras and fitting with formal deformations including deformations of the structure map.