• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.527-533
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• 1997

The purpose of this study is to investigate the fatigue behavior of the reinforced concrete beams strengthened with steel plate and CFS(csrbon fiber sheet). In this study, fatigue loads of 60 to 80 percent of the ultimate strength are applied to the specimens. From the results of test the beams strengthened with steel plate show the flexural failure mode, while the specimens strengthened with CFS fail by separation between CFS and concrete surface. In case of the stress level of 70%, strength degradations of the beams with steel plate and CFS in normalized flexural rigidity at 5,000 cycles is 24 and is 24 and 28 percent respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.598-604
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• 1997

In recent years, strengthening by epoxy-bonded steel plates, carbon fiber sheets, aramid fiber sheets and so on, is spotlighted. Among them, the method using steel plates is most widely applied. Most studies have dealt with strengthening by epoxy-bonded steel plates. However the actual behavior of strengthened RC beams are not well established. Particularly, the studies on the separation load thar affects failure load of the beam are relatively insufficient. In this study, test parameters are the magnitude of pre-load, plate length, plate thickness, existence and spacing of anchor bolt, the number of plate layer and the height of side strengthening, 17reinforced concrete beams are strengthened by steel plates according to test parameters. Deflection, failure load, strains of reinforcing bar, concrete and plate are measured from tests(4 points loading). The failure mode, and separation load are analyzed from these measured data. The difference between Robert's theory and test results is discussed, and the prediction equation for separation load in the case of rip off is proposed.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.239-242
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• 2005

The purpose of this research was focused on substantiating an effects of tendon-layouts and compressed stress($=f_{pc}$) induced by post-tensioning on seismic performance of post-tensioned flat plate slab-column connection designed as non-participating system. To accomplish this purpose, an experimental research of flat plate exterior slab-column connections subjected to gravity load and reversed lateral displacement history are presented. As a result, tendon-layout is a main variable to influence failure mechanism, dissipated energy and lateral deformation capacity. Furthermore, compressed stress ($=f_{pc}$) induced by post-tensioning enhanced the seismic performance of flat plate slab.

• Structural Engineering and Mechanics
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• v.53 no.1
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• pp.131-146
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• 2015

In the present paper a three-dimensional non-linear truss element and a short computer program for the modeling and predicting approximate lateral deflections in thin glass plates by the method of incremental loading are proposed. Due to the out-of-plane large deflections of thin glass plates compared to the plate thickness within each loading increment, the equilibrium and stiffness conditions are written with respect to the deformed structure. An application is presented on a thin fully tempered monolithic rectangular glass plate, laterally supported around its perimeter subjected to uniform wind pressure. The results of the analysis are compared with published experimental results and found to have satisfactory approximation. It is also observed that the large deflections of a glass plate lead to a part substitution of the bending plate behavior by a tensioned membrane behavior which is favorable.

• Structural Engineering and Mechanics
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• v.45 no.2
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• pp.169-182
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• 2013

The mechanical behavior of rectangular foundation plates with perimetric beams and internal stiffening beams of the plate is herein analyzed, taking the foundation design into account. A series of dimensionless parameters related to the geometry of the studied elements were defined. In order to generalize the problem statement, an initial settlements was considered. A numeric procedure was developed for the resolution by means of the Finite Differences Method that takes into account the stiffness of the plate, the perimetric and internal plate beams and the soil reaction module. Iterative algorithms were employed which, for each of the analyzed cases, made it possible to find displacements and reaction percentages taken by the plate and those that discharge directly into the perimetric beams, practically without affecting the plate. To enhance its mechanical behavior the internal stiffening beams were prestressed and the results obtained with and without prestressing were compared. This analysis was made considering the load conditions and the soil reaction module constant.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.168-179
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• 2006

This paper summarizes full-scale test results on CFT column-to-flat plate connections subjected to gravity loading. CFT construction has gained wide acceptance in a relatively short time in domestic building construction practice due to its various structural and construction advantages. However, efficient details for CFT column to flat plate connections have not been proposed yet. Based on the strategies that maximize economical field construction, several connecting schemes were proposed and tested. Test results showed that the proposed connections can exhibit punching shear strength and connection stiffness exceeding those of R/C flat plate counterparts. A semi-analytical procedure is presented to model the behavior of CFT column-to-flat plate connections. The five parameters to model elastic to post-punching catenary action range are calibrated based on the limited test data of this study. The application of the proposed modeling procedure to progressive collapse prevention design is also illustrated.

• Advances in nano research
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• v.12 no.4
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• pp.427-440
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• 2022

In the present study, the nonlocal strain gradient theory is used to predict the size-dependent buckling and post-buckling behavior of geometrically imperfect nano-scale piezo-flexomagnetic plate strips in two modes of direct and converse flexomagnetic effects. The first-order shear deformation plate theory is used to analyze analytically nano-strips with simply supported boundary conditions. The nonlinear governing equations of equilibrium and associated boundary conditions are derived using the principle of minimum total potential energy with consideration of the von Kármán-type of geometric nonlinearity. A closed-form solution of governing differential equation is obtained, which is easily usable for engineers and designers. To validate the presented formulations, whenever possible, a comparison with the results found in the open literature is reported for buckling loads. A parametric study is presented to examine the effect of scaling parameters, plate slenderness ratio, temperature, the mid-plane initial rise, flexomagnetic coefficient, different temperature distributions, and magnetic potential, in case of the converse flexomagnetic effect, on buckling and post-buckling loads in detail.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.23-30
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• 1999

have been many studies to analyze the behavior of metal plate connector that most widely used to connect light frame wood trusses. Finite element method{FEM) was one of the methods for those studies. FEM using linear model may well be applicable to predict the initial slope of load-displacement curve for metal plate connection. However, displacement may be overestimated above experimental results with the increase of load. Therefore, linear model cannot be used for the nonlinear behavior part. To predict real behavior more exactly, nonlinear term was included to FEM model in this study. It was found out that EA and AA mode showed the high agreement between predicted results and experimental ones. However, EE and AE mode showed a little difference between predicted results and experimental ones in nonlinear part. This results might be caused by insufficient reflection of the slip effect. Consequently, the effect of slip shall be considered to approve the accuracy of nonlinear analysis for the behavior of metal plate connection.

• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.277-288
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• 2014

In this study, the local displacement and moment characteristics of a plate stiffened with closed ribs are analyzed according to the dimensions of stiffened plates. The analyzed results of various stiffened plates under square distributed load show that the effect of the loading panel width to the local behavior is dominant but that of the next panel width is very small. And the local behavior of reference stiffened plates can be expressed by the angle between the plate and the rib, and that of other stiffened plates can be obtained by multiplying ratio functions of the loading panel width, plate thickness, rib thickness, rib height and next panel width and they give good results. Applying ratio functions to other loading sizes shows that the applicability of ratio functions except for the loading panel width is proved and the modified ratio functions of the loading panel width improve error ratios. Therefore, the local displacement and moments of a plate stiffened with closed ribs can easily achieve proper results regardless of the dimensions using ratio functions proposed in this study.

• Journal of Korean Association for Spatial Structures
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• v.10 no.4
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• pp.75-83
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• 2010

Laminated composite plates have shown their superiority over metals in applications requiring high specific strength, high specific modulus, and so on. Therefore, they have used in various industry. However, they have poor resistance to impact compared to typical metal materials. So, many researchers have investigated about impact behavior of laminated composite plate. To investigate impact behavior of laminated composite plate, we have to calculate contact force between impactor and laminated composite plate at the first. Impactor's equation of motion, plate's equation of motion and correlations for indentation were solved to know the contact force at the same time. In this study, low velocity impact behavior of composite plate was investigated using the finite element program which is involved the classical Hertzian law, Sun's law and Sun & Yang's experimental law and Sun & Tan's experimental law considering the stacking method.