• The Korean Journal of Health Service Management
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• v.6 no.2
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• pp.71-80
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• 2012

The purposes of this study were to effect the upper extremities strength and ADL with upper extremities in frail elders. This study comparison upper extremities strength to pre-exercise and post-exercise and ADL with upper extremities. 30 elders who was in C silver hospital in Busan after resistance exercise during 12 weeks using elastic band, It was confirmed that improvement upper extremities strength and ADL with upper extremities after resistance exercise. As a result of study about effect of elastic band based resistance exercise on ADL of frail elders, it seems to have good effect on over all items(eating, dressing, bathing, make-up, go to a rest room). Therefore, it is necessary to find method about rehabilitation exercise for frail or partial disability elders.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.245-250
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• 1998

The Elastic modulus depends on the elastic property of composition materials, the gravity of aggregate, the bond strength of binder, the usage and quantity of admixture, curing and measuring method, etc. Accordingly, the aim of this study, by manufacturing concrete of practical high strength range(600~ 1000kg/$\textrm{cm}^2$) with the specific cement and mineral admixtures, is to compare elastic modulus with the existing equations and also to estimate elastic property of use materials. As a result, it could be confirmed that the existing equations which were proposed by the ACI 363, CEB-FIP Code, and New-RC have a tendency to the overestimation in general. However, it could be confirmed that the KCI-96 and Norwegian NS 3473 equations are closed to measuring results, and that the elastic modulus property have a different tendency due to types of cements.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.167-172
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• 2003

Place that have cutout inner bottom and girder and floor etc. in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and change of freight piping etc.. Because cutout's existence gnaws in this place, and, elastic buckling strength by load causes large effect in ultimate strength. Therefore, perforated plate elastic buckling strength and ultimate strength is one of important design criteria which must examine when decide structural elements size at early structure design step of ship. Therefore, and, reasonable elastic buckling strength about perforated plate need design ultimate strength. Calculated ultimate strength change several aspect ratioes and cutout's dimension. and thickness in this investigation. Used program applied ANSYS F.E.M code transformation finite element law that is mediocrity finite element analysis code.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.237-244
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• 2004

Plate that have cutout inner bottom and girder and floor etc. in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and change of freight, piping etc.. Because cutout's existence gnaws in this place, and, elastic buckling strength by load causes large effect in ultimate strength. Therefore, perforated plate elastic buckling strength and ultimate strength is one of important design criteria which must examine when decide structural elements size at early structure design step of ship. Therefore, and, reasonable elastic buckling strength about perforated plate need design ultimate strength. Calculated ultimate strength change several aspect ratioes and cutout's dimension, and thickness in this investigation. Used program applied ANSYS F.E.M code based on finite element method.

• International Journal of Highway Engineering
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• v.7 no.3 s.25
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• pp.63-69
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• 2005

For many years, the compressive strength of concrete has been regarded as an important index in determining concrete pavement quality. The compressive strength of the sample cores from the field has been used as quality index of concrete pavement. However, this process is time consuming and requires a lot of labor. Recently, the M-E Design Methodology in the pavement design based on the elastic modulus has been adopted. Therefore, several NDT methodologies have been adopted for QA/QC in the field and for the pavement design. Among various NDT methods, the wave propagation method can be used to measure the elastic modulus of concrete because the wave velocity is directly related to the elastic modulus. Therefore, in this study the wave propagation method was used for estimating the concrete modulus. The relationship between the compressive strength measured in he laboratory and the elastic modulus measured by the wave propagation method was analyzed, and the compressive strength was estimated from the elastic modulus for various mix types. The results showed that the relationship between the elastic modulus and the compressive strength was observed and the relationship varied depending on the aggregate types.

• Journal of the Korea Concrete Institute
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• v.12 no.2
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• pp.13-20
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• 2000

In this study, the compression test of steel fiber reinforced high-strength concrete have been performed with varying strengths and volume factions of steel fiber. Three types of matrices including low strength concrete( c'=30 MPa), medium strength concrete( c'=50 MPa), and high strength concrete( c'=70 MPa) were selected. Five types of fiber fractions were studied including 0.0%, 0.5%, 0.75%, 1.0%, and 1.5% by volume. From the results of the compressive strength test, the post-peak characteristics of the stress-strain relationship were investigated, and the existing equations to predict the elastic modulus were experimentally evaluated.

• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.391-399
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• 2015

This study modeled the compressive strength and elastic modulus of hardened cement that had been treated with an expansive additive to reduce shrinkage, in order to determine the mechanical properties of the material. In hardened cement paste with an expansive additive, hydrates are generated as a result of the hydration between the cement and expansive additive. These hydrates then fill up the pores in the hardened cement. Consequently, a dense, compact structure is formed through the contact between the particles of the expansive additive and the cement, which leads to the manifestation of the strength and elastic modulus. Hence, in this study, the compressive strength and elastic modulus were modeled based on the concept of the mutual contact area of the particles, taking into consideration the extent of the cohesion between particles and the structure formation by the particles. The compressive strength of the material was modeled by considering the relationship between the porosity and the distributional probability of the weakest points, i.e., points that could lead to fracture, in the continuum. The approach used for modeling the elastic modulus considered the pore structure between the particles, which are responsible for transmitting the tensile force, along with the state of compaction of the hydration products, as described by the coefficient of the effective radius. The results of an experimental verification of the model showed that the values predicted by the model correlated closely with the experimental values.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2550-2563
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• 2022

This study performed a precise dynamic finite element time history elastic-plastic seismic analysis considering the welds, which have been not considered in design stage, on the nuclear components subjected to severe seismic loadings such as beyond-design basis earthquakes for sustainable nuclear power plants. First, the dynamic finite element elastic-plastic seismic analysis was performed for a general design practice that does not take into account the welds of the pressurizer surge line system, one of safety class I components in nuclear power plants, and then the reference values for the accumulated equivalent plastic strain, equivalent plastic strain, and von Mises effective stress were set. Second, the dynamic finite element elastic-plastic seismic analyses were performed for the case of considering only the mechanical strength over-mismatch of the welds as well as for the case of considering both the strength over-mismatch and welding residual strain. Third, the effects of the strength over-mismatch and welding residual strain were analyzed by comparing the finite element analysis results with the reference values. As a result of the comparison, it was found that not considering the strength over-mismatch may lead to conservative assessment results, whereas not considering the welding residual strain may be non-conservative.

• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.161-171
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• 2005

When the in-plane flexural rigidity is small in relation to the applied load, the arch ribs may buckle to the in-plane direction. Designers should therefore determine the in-plane buckling strength. To determine the buckling strength of arch ribs, designers have to consider the material nonlinear response. But in the case of arch ribs having large slenderness ratio, arch ribs may buckle in the elastic range, and when the arch ribs have low slenderness ratio, elastic buckling strength is useful in the preliminary design. In this paper, elastic buckling strength of arch ribs, which are frequently used in practical design, is studied using nonlinear finite element method. In general, the relation between flexural rigidity and elastic buckling strength is linear. As seen from the results, however, when the arch ribs have low slenderness ratio, the relation between flexural rigidity and elastic buckling strength is nonlinear.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.213-218
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• 2006

As a manufacturing process of recycled aggregate improves the quality of recycled aggregate shall be sufficient enough to be used for structural concrete. This study characterized compressive strength and elastic modulus of concrete that used recycled coarse and fine aggregate. Before the strength tests, the fundamental characteristics of recycled aggregate were preliminarily analyzed and the recycled aggregate satisfied the class 1 requirements in KS F 2573. As the replacement ratio increased, the compressive strength and elastic modulus of recycled aggregate concrete decreased. When the coarse and fine aggregates were completely replaced with the recycled, the compressive strength and elastic modulus were decreased by 13% and 31%, respectively. Based on the test results, this study suggests equations for predicting the compressive strength and elastic modulus of the recycled aggregate concrete with respect to the replacement ratio. The values from the equations were in good agreement with the test data from this study and others.