• Magazine of the Korea Concrete Institute
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• v.6 no.3
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• pp.215-220
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• 1994

Results of an experimental investigation on the bearing strength and stiffness of concrete under dowel bars are summarized. The effects of concrete strength bar diameter, and location of the bar on concrete were studied. Based on test results, empirical equations are proposed to predict the, concrete bearing strength and stiffness under reinforcing bars. Cornparisions of analytical arid experimental results are presented.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.129-136
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• 2012

Compression splices are required for all compression members in almost all of the floors in high-rise buildings. Therefore, a clear understanding of the behavior of compression splices can provide a rational design of compression splices. Tests of compression splices with bearing only and bond only cases were conducted to investigate the component resistance characteristics of compression splices. Test results showed that the circumferential tensile stresses induced by bearing and bond overlapped at the end of the splice length deterred bond and bearing splices from developing target splicing strength when both normal bond and bearing splices were used. In particular, the bearing strength was more significantly reduced than the bond strength since the bearing relied on the limited area near the end of the splice length. However, the strength of the normal splice was always higher than the strength of the bond only or the bearing only case. Consequently, the study results showed that splice strength in compression cannot be improved by means of removing bond or bearing. In addition, the bond strength in bond only splices was nearly same as the bond strength in tension splices and the strength increase of compression splice is attributed to end bearing only characteristic.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.417-424
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• 2003

A bearing failure in RCS(Reinforced Concrete Column and Steel Beam) system is recognized as one of the distinct joint failure modes for the composite frames. Vertical and transverse reinforcement in addition to concrete are effective for better transfer of vortical forces through concrete bearing. To examine the effect of the vertical bars, tie bars, a U-type detail developed in this study and concrete confinement, local bearing tests were conducted using 22 small-scale concrete block specimens. Test results show that vertical reinforcement and tie bars mainly contribute to the bearing capacity. However larger amounts of tie reinforcement are required than those recommend from ASCE guidelines, to apply the nominal concrete strength as 2 $f_{ck}$ over the bearing area. Cross ties are proved to be highly effective for resisting the vertical forces. Maximum bearing strength can be increased upto 2.5 $f_{ck}$ . An accurate prediction model for bearing strength is proposed for better design of the composite Joint.

• Journal of Korean Society of Steel Construction
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• v.15 no.6 s.67
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• pp.683-691
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• 2003

Recently, the steel has been increaseingly used as an integrated part of high-rise buildings, which often composed of steel structures, steel reinforced concrete structures and composite structures. The steel base is designed to transfer the stresses induced from steel column to the reinforced concrete footing through the base plate. However, in the design of steel structures and steel reinforced concrete structure, it is generally difficult to evaluate the bearing strength of the steel base subjected to large axial force. Furthermore, the material used in steel base is quite different from those used in other connections and a load transferring mechanism of steel base is very complicated in nature. Therefore, a special attention must be placed in design and construction of steel base. In generally, the bearing strength test and research of the steel base subjected to concentrated load are carried out. But, in the design of the structures, uniaxial eccentric load is loaded to the steel base of the steel structures. In this research, the bearing strength and the me of failure considering eccentric loads and eccentric length, were experimented when eccentric load is loaded to the steel base of steel structures. Based on the test results, a basic design reference is suggested for a reasonable design of steel structures, steel reinforced concrete structures and composite structures.

• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.341-352
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• 2017

Well designed group bolted connections can exhibit excellent ductile behavior through the bearing mechanism until the occurrence of shear rupture in the bolt or in the connecting plate. This excellent ductility can be utilized in favor of economical connection design. In this study, comprehensive tests on single-bolt bearing connections were conducted and analyzed considering bearing boundary conditions. The primary objective was to propose a generalized bearing strength and load-deformation relationship that can be used for designing group-bolted connections. To this end, new bearing strength formula, deformation limits as well as new load-deformation relationship were first proposed. Especially the proposed load-deformation relationship can reflect the stiffness, strength, and geometrical boundary conditions of the joint. The proposed formula and relationship are validated based on test results.

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.291-302
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• 2009

A compression lap splice can be calculated longer than a tension lap splice in high strength concrete according to current design codes. New criteria for the compression lap splice including the effects of concrete strength are required for practical purpose of ultra-high strength concrete. Characteristics of compression lap splice have been extensively investigated and main parameters are derived. In addition, an experimental study has been conducted with column specimens in concrete strength of 40 and 60 MPa. The strength of the compression lap splice consists of bond and end bearing and two contributors are combined. Therefore, combined action of bond and end bearing should be assessed. Compared with tension splices, concrete strength significantly affects the strength of compression splices due to short splice length and existence of end bearing. Test results show that the splice strength can be evaluated to be proportional to square root of compressive strength of concrete. The stress states of concrete surrounding spliced bars govern the strengths of bond and end bearing. Because the axial stress of the concrete is relatively high, the splice strength is not dependent on clear spacing. End bearing strength is not affected by splice length and clear spacing and is expressed with a function of the square root of concrete strength. The failure mode of specimens is similar to side-face blowout of pullout test of anchors and the strength of end bearing can be evaluated using the equation of side-face blowout strength. Because the stresses developed by bond in compression splices are nearly identical to those in tension splices, strength increment of compression splices is attributed to end bearing only.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.93-101
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• 2008

Bearing strength test was investigated to determine the bearing properties of domestic larix glulam according to the load direction (in parallel to grain and in perpendicular to grain), the fastener (bolt and drift-pin), and the direction of laminae. The specimen was 5 ply glulam. The diameters of fastener are 12, 16 and 20 mm. The results were as follows. 1) In according to the diameter of bolt and drift-pin, the average of maximum bearing strength in parallel to grain loading was similar to that in perpendicular to grain loading. The average of maximum bearing strength was 1.50~2.31 times higher in parallel to grain loading than in perpendicular to grain loading. The average of maximum bearing strength in parallel to grain loading was lowered by 20% with increasing the diameter from 16 mm to 20 mm, but that in perpendicular to grain loading didn't show a clear tendency. 2) The average of bearing stiffness in parallel to grain loading was the highest at 16 mm in diameter. The average of bearing stiffness is similar to the shearing stiffness in drift-pin connection with increasing diameter. 3) In parallel to grain loading, the failure mode of specimens was the splitting along the grain in decreasing diameter. The failure mode in perpendicular to grain loading was the splitting along the grain. In this case, split occured more in specimens using bolt than in those using drift-pin. 4) The 5% offset yield strength in parallel to grain loading was similar to the predicted bearing strength of KBCS, NDS. In perpendicular to grain loading, the NDS's equation can be applied to predict the bearing strength.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.8-15
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• 2018

Hollow Core Slab is a very efficient system that can reduce weight and its use has increased. Void slab is a concrete slab that has voids substituted with void material. Because of its saved volume of concrete, void slab can reduce weight of slabs. Also, it can't only save concrete but also can reduce carbon-emission. However, because of the unclear bearing strength at the part of void substituted with voiding material, several problems occur in constructing field. In this study, void slab including void material was built and local bearing strength test was carried out for 3 types of load(truck load, support load and Jack support load). As a result, bearing strength of void neck and upper void material is more than allowable load. And also, bearing strength of specimens with using deck and not using deck are also over allowable loads.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.38-46
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• 2023

In this study, a bearing test was performed and analytically evaluated to evaluate the bearing performance according to the application of the aluminum stiffener in round-end concrete. In the bearing strength test, the change in bearing performance due to the aluminum stiffener using the aluminum form for manufacturing concrete with round-end, and the steel anchor bolts for member movement and assembly was confirmed. The FE analysis model was identically configured to the experimental conditions, and the result was compared with the experiment. Also, the crack patterns and stress behavior were confirmed. In addition, the effect of strength change of the aluminum stiffener on the round-end concrete was also evaluated analytically. The bearing strength of the round-end concrete increased by about 20% due to the aluminum stiffener, and it was confirmed that the steel anchor bolt did not affect the bearing strength. The maximum load and crack patterns shown as a result of FE analysis were similar to those of the experiment. As a result of FE analysis according to the strength change of the aluminum stiffener, the maximum load change according to the increase and decrease of the strength of the aluminum stiffener by 10% and 20% was evaluated to have no significant effect at a maximum of about 4% compared to before the strength change.

• Journal of Korean Society of Steel Construction
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• v.18 no.1
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• pp.81-91
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• 2006

The corrugated web is a plate that was manufactured with a corrugated shape. It is widely used in bridges, buildings, and culverts. A girder with a corrugated web can be crippled by local, in-plane compressive loads. Due to its high out-of-plane strength, however, a stiffener is usually not needed in trapezoidally corrugated plates, and the corrugated profile of the web can change the boundary condition of the edge load. Some researchers have studied the strength of the partial-edge loading of the trapezoidally corrugated web, but they have not considered the profile of corrugation in their studies. This paper investigates the influence of the corrugate profile. A parametric study was conducted on the shape parameter using the finite-element method. In this parametric study, the relationship between the corrugated shape and the partial-edge strength was also investigated by dividing the partial-edge strength into the web capacity and the flange capacity.