• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.138-145
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• 2001

This paper presents F.E.M. analysis result about the behavior of R.C. beam repaired with steel plate and fiber sheet. The effect of repairing varies with reinforcement ratio of R.C. beam, plate thickness, numbers of fiber sheet, and repairing length, etc. F.E.M. analysis using a program, DIANA, was carried out taking these factors as parameter in this study. Analysis result shows that repaired R.C. beam behaves differently according to parameters and certain cases imply that repairing is useless or may lay structure in dangerous condition. F.E.M. model considers that interfacial behavior between different two parts of repaired beam is rigid based on an assumption that adhesive failure does not appear before yielding of reinforcement and its analysis shows the result coincides with that of experiment.

• Journal of the Korean Society of Safety
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• v.24 no.6
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• pp.93-102
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• 2009

Because steel girder bridge has big slenderness ratio, buckling is very important in design. Local buckling of plate girders having two longitudinal stiffeners in different positions under various load conditions is investigated. Various parametric study according to the change of web height, transverse stiffeners and load conditions are examined. These parametric studies are performed by numerical simulation utilizing finite element method. The objective of this study is to present the rational reinforcement location of two longitudinal stiffeners. The results of analysis are compared to that recommended by korean specifications for road bridges(2003).

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.2
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• pp.1-8
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• 2014

In the past, Korea was classified as a region not affected by earthquakes. However, recent increase of earthquakes has forced to strengthen standards of earthquake resistant designs of structures to minimize seismic damage. In addition, it was thought that masonry infill walls in buildings are only acting as partitions, so these walls are not considered in analyzing building structures. But it was found that when seismic loads are applied to a structure with masonry infill walls, the walls affect the structure. Accordingly, this study conducted nonlinear static analyses for a structure constructed before applying earthquake resistant designs in two cases: when considering masonry walls and when not. The result showed that the seismic performance of the structure is insufficient. Thus, the structural resistance of the structure was also studied in two cases: when reinforcing with steel plate braces and when using carbon fiber braces. In the two cases reinforcing two different stiffeners, it was appeared that the behaviors of the structure were similar, though the cross-section area of a carbon fiber brace used to reinforcing the structure is only 12.6% of a steel plate brace, and its weight is only 2.8%. Thus, the reinforcing effect of the thin, light-weighted carbon fiber brace is much larger than that of the steel plate brace, when considering usability and constructability of both materials.

• Steel and Composite Structures
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• v.43 no.1
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• pp.107-116
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• 2022

This paper presents results of numerical studies completed on unreinforced and doubler plate reinforced Elliptical Hollow Section (EHS) T-joints subjected to axial compressive loading on the brace member. Non-linear finite element (FE) models were developed using the finite element code, ABAQUS. Available test data in literature was used to validate the FE models. Subsequently, a parametric study was carried out to investigate the effects of various geometrical parameters of main members and reinforcement plates on the ultimate capacity of reinforced EHS T-joints. The parametric study found that the reinforcing plate significantly increases the ultimate capacity of EHS T-joints up to twice the capacity of the corresponding unreinforced joint. The thickness and length of the reinforcing plate have a positive effect on the ultimate capacity of Type 1 joints. This study, however, found that the capacity of Type 1 orientation is not dependent on the brace-to-chord diameter ratio. As for type 2 orientations, the thickness and length of the reinforcement have a minimal effect on the ultimate capacity. A new design method is introduced to predict the capacity of the reinforced EHS T-joints Type 1 and 2 based on the multiple linear regression analyses.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.6
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• pp.667-674
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• 2015

In this paper, shear behavior of concrete wide beam reinforced with plates with openings was evaluated. For this evaluation, evelen specimens were manufactured. One specimen was non-shear reinforced, five specimens were reinforced with steel plates and the other five specimens were reinforced GFRP plates. Shear strengths measured through experiments were compared with ones calculated from the equation provided by ACI 318. Longitudinal spacing of shear reinforcement, transverse spacing of shear reinforcement and shear reinforcement material were considered as variables. Test results showed that the shear strength increased as the transverse and longitudinal spacing of shear reinforcement became narrow. Also, regardless of material type of shear reinforcement, the shear capacity was similar when the amount of shear reinforcement was the same.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.804-807
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• 2002

In general, the reinforcement of a structure is performed with cylinders. In this study, it is attempted to analyze the circular reinforcement with fins. And the maximum stress and deflection is investigated fur the circular reinforcement between two plates. The shape of models are : one which has only circular reinforcements of different diameters and one which has circular reinforcements with fins and one which has fin of same length and circular cylinders of different diameters. And in each model, there are two kinds; one is with upper and lower plates and the other with none. The results shows that the maximum stress is less in the model of circular reinforcement with fins than that in the model without fins. And the maximum stress of a model without upper and lower plate is less than that of a model with plates.

• Journal of the Korea Institute of Building Construction
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• v.13 no.5
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• pp.482-490
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• 2013

Although the flat plate system is an efficient structural type due to the simplicity of its construction, the low story height, and the various plan design, the slab-column connections are vulnerable to punching shear failure from gravity load and eccentric shear failure from lateral load. To prevent the structure collapse, various construction methods of slab-column connection reinforcement are developed but none of these satisfies all of structural performance, economics, and constructability. This paper presents the reinforcement of slab-column connection with lattice bars. The structural performance is confirmed with the interior slab-column connection tests subjected to cyclic loading, and the economic feasibility is demonstrated from the structural design under the same condition with lattice bars, stud rails, and stirrups.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.4
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• pp.99-108
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• 2007

In the flat-plate slab design of the KCI and ACI building code, the punching shear strength of connections with shear reinforcement can increase one and half times to that of connections without shear reinforcement. And the ACI-ASCE committee 352 recommendations propose limiting the direct shear ratio $V_g$/$V_c$ on interior connections to 0.4 to insure adequate drift capacity. In this study, four interior column-slab connections were tested to look into the punching shear strength and the lateral displacement capacity of the flat-plate slab with and without shear reinforcement under cyclic lateral loading. Based on the test results, it is found that the provision about punching shear strength in the codes may appropriate for the gravity loading only whereas it is unconservative for the lateral loading and that the limit of ACI-ASCE committee 352 appears conservative.

• Journal of the Korean GEO-environmental Society
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• v.13 no.6
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• pp.5-17
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• 2012

The study of surface ground reinforcing method is supposed to be considered preferentially is not satisfied and also doesn't contemplate plastic flow because of repetitive drive of construction equipment. Also, Terzaghi's bearing-capacity equation and Yamanouchi's suggestion have been used to design the surface reinforcement, but most engineers depend on their experience and cases constructed before because of dispersed variables and inappropriate bearing-capacity factors. Hence, plate load test and repetitive plate load test were performed in the field which is reinforced with geotextile, Geogrid whose tensile strength are 200kN/m, 100kN/m and bamboo($0.4m{\times}0.4m$). The object of this study is to evaluate bearing capacity and behaviour of surface ground and to compare each reinforcement form test results. From the results bearing capacity ratio increased by a maximum of 1.5 times with bamboo reinforcement method comparing to others.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.211-218
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• 2006

From the development of residential flat plate system, continuously bended shear reinforcement is developed for the prevention of punching shear. To know the punching shear capacity of developed shear reinforcement in slab-column joint, structural test is performed. The testing parameters are shear reinforcement types, such as no reinforcement, bended shear reinforcement, and head stud reinforcement. To verify the lateral capacity, cyclic load is applied under the constant vertical load condition. The results of tests are compared to as global displacement, slab-column joint strength. From the test results, the resisting capacity of developed shear reinforcement system has a good performance in the story drift ratio.