• Journal of Korean Society of Steel Construction
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• v.12 no.5 s.48
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• pp.595-604
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• 2000

Web openings of large beams provide space for wiring, piping, and duct work to provide for proper drainage, pipes and duct must be slightly sloped with the attendant result that all web openings can not be centered on the centroidal axes of the beams. Test specimens are made for opening-depth to beam-depth ratio of 0.5 and for eccentricities of the opening center line of 10% from middepth of the beam because of the proximity of the opening edge to the flange. In this paper, available test results and theories relating to the strength of composite beams having eccentric rectangular openings are surveyed and experiments were carried out to examine the structural behaviors. In all the tests in this paper good agreement is demonstrated with maximum loads measured in tests, and observed failure modes Furthermore, compared with analytical values and experimental values of interaction diagram between moment and shear capacity were safed as it is scattered with outer part of the analytical values.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.67-73
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• 2017

Recently, the demand for large diameter piles has been rapidly increased in order to secure the allowable bearing capacity of pile foundation due to the increase of large structures such as high rise buildings. In this study, to improve the shear capacity of a conventional PHC pile, a large diameter composite PHC pile strengthened by in-filled concrete and shear reinforcement was manufactured. All the piles were tested according to the shear strength test method of Korean Standard. As a result of the shear test, the F-type piles which are produced without shear reinforcement occurred abrupt horizontal cracks after flexural and inclined shear cracks occurred. On the contrary, the FT-type piles which are produced with shear reinforcement exhibited stable flexural and inclined shear cracks uniformly over the entire pile without abrupt horizontal cracks. Furthermore, the maximum load of the large diameter composite PHC pile improved to 2.9 times in the F series, and more than 3.3 times in the FT series compared to the conventional PHC pile. This result indicated that FT-type piles had excellent composite behavior due to the shear reinforcement and effectively prevented the unstable growth of inclined shear cracks.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.75-87
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• 2009

In this study, FEM analysis has been performed based on the results from domestic experimental researches regarding to material and member characteristics of masonry. After validation of reliability for the used FEM analysis method, this study is progressed the evaluation of seismic capacity for existing prototype masonry building in Korea. According to the evaluation for the prototype masonry building, the horizontal shear force and the average shear stress are similar to those of previous studies.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.83-91
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• 2017

In order to cope with the abnormally high waves during the storm surge due to climate change, various methods have been proposed for interlocking adjacent caissons to enhance stability of harbor structures. Among the methods, it was studied the method based on an open-cell caisson having reduction effect increasing the cohesion with adjunction caissons by filling materials such as crushed rocks in an inter-cell formed by two facing open-cells which consist of transverse walls. It is necessary to investigate the shear behaviors of an inter-cell to secure the stability using calculating shear forces on inter-cell under oblique wave loadings. It was analyzed the shear force share ratio with the length of internal and external wall and the number of internal walls. Numerical results show that 60~70% of the shear load is transmitted to adjacent caisson through the internal walls, more than 30% is through the external wall. It was applicable in the assumption that filling materials was uniformly distributed in inter-cells, and further studies were worth consideration on other conditions under construction.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.2
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• pp.105-113
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• 1999

This paper resents a prediction method of natural frequencies of coupled horizontal and torsional vibration of hull girder based on design sensitivity analysis in case of the changes of system parameters. The sensitivity analysis is formulated applying the direct differentiation method and transfer matrix method. In the analysis, warping, shear deformation due to torsion and the continuity condition at the connected part of open and closed hull section are considered. Using the presented method. The affection for natural frequencies by the change of system parameters, especially cargo and added mass and their centers, is numerically investigated for a real large container carrier.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.277-291
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• 1983

In order to investigate the shear characteristics of earth structure after construction. Four sample soils with different gradation were selected and compacted under the optimum moisture content and the maximum dry density. And the direct shear test and the triaxial compression test were performed with those sample soils under various pre-compression loads. The results were summarized as follows; 1. With the increase of the percent passing of No. 200 sieve, the cohesion of soil increased regularly and the internal friction angle of soil decreased with slow ratio. 2. The pre-compression increased the shear strength of compacted cohesive soil. The increase of cohesion was very apparent but the internal friction angle didn't show such regular tendency. 3. With the increase of pre-compression load, the slope of stress-strain curve showed steep at the early stage of horizontal strain. The vertical strain was small at the compression stage and big at the expansion stage. 4. When the vertical stress of shear test with increase in the horizontal strain was small, stress ratio(shear stress vs. vertical stress) of sample showed the largest value and the slope of stress ratio curve showed also steep. 5. When the sample was had the same condition, the cohesion of soil showed bigger value in the triaxial compression test and the internal friction angle of soil showed bigger value in the direct shear test.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5C
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• pp.255-262
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• 2008

In order to investigate the strength anisotropy of compacted materials, a series of unsaturated and saturated-drained triaxial compression tests was performed. Three different orientation angles of the axial direction of samples with respect to the horizontal plane were investigated: ${\delta}=0$, 45 and 90 degrees. As the results showed, the suction rate on the strength of the unsaturated specimen was not influenced by ${\delta}$. And the effect of the angle ${\delta}$ on the strength was more pronounced on unsaturated specimen as compared to saturated specimen. Moreover, a new procedure was proposed to take into account the effect of the angle ${\delta}$ on the shear strength of unsaturated soils.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.43-50
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• 2018

In this study, to investigate the shear connection material for the composite of steel plate and bottom plate, design standards and research cases for shear connectors in various countries around the world were analyzed and shear tests were performed on the Push-out specimens with a shear connection, which transmits the horizontal shear force developed on the contact surface between the steel plate and the concrete slab due to various vertical loads acting on the bridge deck. Through Push-out tests of shear studs, of which FRP bar instead reinforcement is placed, the shear stud evaluation formula of the steel strap bottom plate was suggested. The suggested equation suggested in this study has the safety factor of approximately three times compared to allowable strength of highway bridge design criteria. In addition, compared to existing DIN standards and Viest assessment equation, the results showed similar values(approximately, 5% error).

• Computational Structural Engineering
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• v.11 no.1
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• pp.251-259
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• 1998

Concrete shear wall with opening is modeled as a rectangular thin plate. The stability analysis results are presented by the buckling coefficient, k, for two different boundary conditions. The other parameters whose variation have been considered are the ratio of the bending induced force to gravity force, a, the ratio of the horizontal shear force to the gravity force ratio, A and the change of location and the size of perforated part. To obtain the results by finite element method, an example plate has been divided into 27*9 square elements. Four node rectangular c.deg. continuous finite elements having three degrees of freedom per each node is adopted. It is generally concluded that the buckling coefficients decrease as the size of hole increases, and the location of hole moves to free edge of the wall.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.260-270
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• 1998

The field tests were performed to suggest the rational method for stability evaluation of soft clay. The behavior of settlement-displacement obtained by field monitoring system was to compare and analyze the results of the observationed method, and to investigate the complex behavior of soft clay with filling height. The results of this study are summarized as follows. 1. The horizontal displacement was suddenly increased when physical properties of soft clay showed maximum values and the part of the turning point. The values of these properties were available to the fundamental data for stability evaluation. The shear deformation appeared that difference of the horizontal displacement was maximum values. 2. Although the stability of embankment by step filling showed the unstable part over the failure standard line, the embankment was confirmed stable. So the evaluation of the stability of embankment is reasonable to use the inclination of curve than failure standard line. 3. The horizontal displacement and relative settlement were increased as same ratio at improvement ground. Estimation of shear deformation using Terzaghi's modified bearing capacity should consider the relations of embankment load and undrained shear strength at nonimprovement ground, and minimum safety factor is recommended to use larger than 1.2. 4. Excess pore water pressure was increased with increasing of filling height and decreased with maintain the filling height. The embankment was unstable when filling height was exceed the evaluation standard line, and the behavior of excess pore water pressure and horizontal displacement could use as a standard of judgement of the filling velocity control because their behavior were agree with each other.