• Journal of Ocean Engineering and Technology
• /
• v.3 no.2
• /
• pp.118-124
• /
• 1989

In this paper a design formula has been proposed to predict the residual strength of damaged tubulars subjected to combined axial copression, hydrostatic pressure and end bending loadings. A theoretical analysis method was employed to calculate the residual strengths, in which the geometric configuration of damaged tubulars is realistically described using empirically derived equations. The predictions using this method have been compared with relevent experimental results to demonstrate their validity and accuracy. A rigorous parametric study has been conducted using the method, and then a design formula has been derived based upon the parametric study results.

• Journal of Ocean Engineering and Technology
• /
• v.3 no.2
• /
• pp.618-618
• /
• 1989

In this paper a design formula has been proposed to predict the residual strength of damaged tubulars subjected to combined axial copression, hydrostatic pressure and end bending loadings. A theoretical analysis method was employed to calculate the residual strengths, in which the geometric configuration of damaged tubulars is realistically described using empirically derived equations. The predictions using this method have been compared with relevent experimental results to demonstrate their validity and accuracy. A rigorous parametric study has been conducted using the method, and then a design formula has been derived based upon the parametric study results.

• Journal of the Korea Concrete Institute
• /
• v.16 no.2 s.80
• /
• pp.269-275
• /
• 2004

Factorial design method is applied to investigate the effects of various factors simultaneously rather than to conduct a series of single-factor experiment. As the results, frost resistance of the concrete specimens, in both W/C ratio of 0.28 and 0.35, was highly affected by the type of coarse aggregate that is, andesite produced more durable concrete than the limestone. Durability factor of the specimens, with W/C ratio of 0.28, which were demolded after I day and transferred to the curing room was higher than those demolded after 2 days. This stated the efficiency of the high early curing in high strength concrete.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.7 no.3
• /
• pp.37-42
• /
• 1998

The important parts of the developing AGV model are the fabrication of each part and the design technology of body frame. In the present day, design of the body frame depends on the experience of the industrial place. the systematic data need for the optimal design of the frame for the case of model change. In this study, the strength of the early stage AGV(Automatic guided vehicle) is examined with the 3-dimensional finite elemnt method. In order to verify the finite element results, the computed results are compared with the experimental data from the strain-gage output. A New model was designed by rmoving some parts of the early staged(roughyly designed) model and choosing the thickness change of the rectangular-pipes.

• Computers and Concrete
• /
• v.27 no.3
• /
• pp.211-223
• /
• 2021

This paper presents a review of the two widespread approaches which deal with the ultimate strength design of RC slabs subjected to bending moments and torsion: The Field of Moments Method (FoMM) and the Sandwich method (SM). Special attention is paid to the ultimate strain distribution implicitly assumed when using each one of the methodologies, in particular, the yielding of the steel reinforcement. This work analyzes the initial assumption regarding ultimate strain distribution in the SM. Furthermore, this work studies the resisting moments field on which the Wood-Armer method is based, and it finds some inconsistencies. Several examples have been developed.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.11a
• /
• pp.279-282
• /
• 2005

Experimental study is performed to investigate the variation of shear strength of reinforced concrete beams according to design parameters. The major parameters are loading condition, shear span-to-depth ratio, ratio of tensile longitudinal reinforcement, prestress and boundary rigidity.14 reinforced concrete beams without web reinforcement are tested under monotonic downward loading. The shear strength of the tested specimens were compared with the prediction by design code and Choi's method.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1993.10a
• /
• pp.632-637
• /
• 1993

Rating systems of bevel gears(straight, spiral, and zerol bevel gears) which are commonly used as power transmission devices for non-parallel axes are developed on the personal computer, which analyze and/or evaluate the gear design and the service performance at the point of view of strength and durability. The typical considerations of the ratings are the bending strength the surface durability, and the scoring resistance. The ratings are carried out using the reliable standards of AGMA & Gleason Works. Therefore, the system is built so that the variables or factors considered differently in those standards and the strength, durability, and scoring partially in Gleason are appraised separatedly by each method, and a series of the estimation processes is integrated into the system so as to compare each result. The developed rating system can be used in the initial stage of gear design process, and also a better design can be performed by the evaluation of the initial design at the view point of gear strength and durability. Additionally, it is useful for the trouble-shooting of bevel gear systems and to the purpose of introducing the methods for maintaining design strength in service with appraising the gear strength after design or with appraising the influencing factors, as a whole. Therefore, this rating systems can help the aim of design automation of bevel gears.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.301-304
• /
• 2006

Tower shell design is very important because tower takes about 20% of overall wind turbine cost. This paper contains procedure of tower analysis and optimization content. Some of requirements like eigenfreauency and buckling evaluated by numerical method, strength, are derived by analytic method. But strength and fatigue can be derived by mathematical method simply.

• Particle and aerosol research
• /
• v.8 no.2
• /
• pp.75-81
• /
• 2012

The strength of lumped cokes can be represented by some index numbers. Although some indexes are suggested, these indexes are not enough to enlighten fracture mechanism. To find essential mechanism, a computational way, discrete element method, is applied to the uniaxial compression test for cylindrical specimen. The cylindrical specimen is a kind of lumped particle mass with parallel bonding that will be broken when the normal stress and shear stress is over a critical value. It is revealed that the primary factors for cokes fracture are parallel spring constant, parallel bond strength, bonding radius and packing ratio the parallel bond strength and radius of the parallel combination the packing density. Especially, parallel spring constant is directly related with elastic constant and yield strength.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.7 no.2
• /
• pp.239-246
• /
• 2003

In the PCA Load Contour Method, the biaxial bending design coefficient of columns(${\beta}$) is based on the equivalent rectangular stress block (RSB). And coefficient of ${\beta}$ estimates the reinforcement index to be a influencing parameter on biaxial moment strength of RC columns without considering the arbitrary condition of bar arrangement. The experimental results of high strength concrete (HSC) columns subjected to combined axial load and biaxial bending moment were compared to the analysis results of RSB method. As result, the accuracy of RSB method is still acceptable for HSC columns and, as the reinforcement is placed densely in each corner of column section, the ${\beta}$ is decreased.