• Journal of Korean Society of Steel Construction
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• v.23 no.1
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• pp.29-39
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• 2011

With regard to steel construction, many studies have been performed to examine the structural behavior of the bolted connections domestically and in other countries. Especially, a domestic study was conducted on the block shear fracture and shear lag effect on the single-bolted angle connection in carbon steel. In this study, specimens were prepared with the end distance parallel to the loading direction and bolt arrangement ($1{\times}1$, $1{\times}2$), as the main variables. Then the fracture mode and the curling effect on the bolted angle connection in austenitic stainless steel were investigated. Moreover, the fracture mode and ultimate strength were compared, and the strength reduction by curling was estimated.

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.283-290
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• 2006

The paper describes m experimental study on the shear strengthening of concrete beams with exposed wire rope. The strengthening method is using the mechanical bolting of wire rope tensioned on the exterior of beam section. There are two shear strengthening types. The first is closed type wrapped beam section with wire rope like as closed stirrup. The second is U type tensioned at the anchor located in the side of beam section. The main parameters of specimens are strengthening spacings of wire rope with 150, 200, and 250mm for the closed and U type respectively. The shear span ratio of specimens applied by 3-point loading is 4. The results showed that the ultimate shear strength and ductility of strengthened beams increased significantly compared with non-strengthened beams. Especially, the strengthening effect of closed type was very preferable to U type. Therefore, the shear strengthening method with wire rope is very reasonable in view of repair and rehabilitation of beams.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.7
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• pp.120-128
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• 2019

It is very important to verify the seismic performance and stability of the power plant fixture in the domestic power plant, because earthquakes have increased in frequency around the world which resulted in the frequent occurrence of power plant damage caused by the failure of electric power facilities. In this study, through the on-site inspection of power plant fixation unit installed in domestic power plants, we carried out structural performance evaluation of the fixation unit anchor bolts installed on the concrete slabs. The field survey showed M12 J hook anchor bolts were used. Anchor bolt pullout and shear performance evaluation were performed based on ASTM E 488-96 standard. Moreover, artificial crack with the width of 0.5 mm was applied during the experiment based on ATM355.4 and ETAG 001. The comparison of M12 J hook anchor bolt pullout and shear test result to design value required in domestic and international design standard, show a satisfactory result. M12 J hook anchor pullout and shear performance was found to be about 35% and 7%, respectively, higher than the required design value.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5566-5571
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• 2012

Block shear failure is one of limit states, and demands great caution in designing the tension member or connection joint of steel structures. From many studies and design specification, it is shown that the effect of the bolted connection type on the block shear failure was not considered. In order to investigate the effect of the bolted connection type(bearing type connection and slip critical connection) on the mode/strength of the block shear failure, tensile experiment is conducted in this study. Differences about the failure mode according to the design specification, bearing type connection, and slip critical connection are proposed from the analysis of test results. The variation of the block shear failure strength due to the frictional force in the slip critical connection is also investigated.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.2
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• pp.1-12
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• 2017

In this study, It was purpose to provide preliminary data for extension of the applicability of deep corrugated steel plate composite members by steel grade and shear reinforcement method. From the result of flexural test on deep corrugated plates composite members using GR40 and SS590, positive moment capacity was increased about 28% by SS590 steel. But to change steel grade was proved to have insignificant effects for increasement of negative moment capacity. In the moment test result of same overlapping length, Increasement rate of positive and negative moment capacity was not significantly improved by increasing the number of bolt. It was estimated to be due to the characteristics of bolt connection such as distance between centers of bolts, edge distance of bolt. In the test result on the spacing of shear reinforcement, positive moment capacity was increased and deformation of negative moment was reduced as the distance decrease. In the test result on the shape of shear reinforcement, positive and negative moment resistance was increased about 2% ~ 7% by U shaped shear reinforcement. In conclusion It was estimated that moment capacity of deep corrugated steel plate composite members are depend on steel grade of deep corrugated steel plate, spacing of shear reinforcement and reinforcing bar.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.10-21
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• 2014

The joint of prefabricated steel grid composite deck is composed of concrete shear key and high-tension bolts. The flexural and shear strength of the joint were experimentally evaluated only by the bending and push-out test of the joint element. In this study the lateral load transfer behavior of the joint in deck structure system is experimentally evaluated. Several decks connected by the joint are prefabricated and loaded centrically and eccentrically. In the case of centrically loaded specimens, the analysis results show that for the same loading step the rotation angle of the joint with 4 high-tension bolts is larger than the case of the joint with 9 high-tension bolts. Consequently, flexural stiffness of deck and lateral load transfer decrease in the case of specimen with 4 high-tension bolts. But, in the case of eccentrically loaded specimens, it is found that there are no significant differences in the load transfer behavior. The further analysis results about the structural behavior of the joint show that lateral load transfer can be restricted by the load bearing capacity of the joint as well as punching shear strength of the slab. Furthermore, considering that high-tension bolts in the joint didn't reach to the yielding condition until the punching shear failure, increase in the number of high-tension bolts from 4 to 9 has a greater effect on the flexural stiffness of the joint and deck system than the strength of them.

• Composites Research
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• v.34 no.2
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• pp.101-107
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• 2021

Composite structures have components and joints. Theses connections or joints can be potentially weak points in the structure. The failure mode of the composite bolted joint is designed as a bearing failure mode for structural safety. The load-displacement relation exhibits bearing failure mode shows a nonlinear behavior after the initial failure and progressive failure behavior. In order to accurately predict the failure behavior of composite bolted joints, this study modified the shear damage variable calculation process in the existing progressive failure analysis model. The results of the bearing stress-bearing strain of the composite bolted joint were predicted using the modified progressive failure analysis model, and the modified model was verified through comparison with the previous progressive analysis model.

• Journal of the Korean Wood Science and Technology
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• v.33 no.1 s.129
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• pp.7-16
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• 2005

This study was carried out to evaluate the structural property of double shear bolted connections in Korean Larch. For the main member, sawn lumber and Glulam were used in which thickness of lumber is 39 mm, 89 mm, 139 mm, 189 mm and Glulam 80 mm, 140 mm, 170 mm. For the side member, sawn lumber and steel plate were used in which thickness of lumber is the same of the main member and steel plate is 6mm. And connections were jointed by M12, M16, M20 bolts which were usually used for wood constructions in Korea. Directions of loading to connections were perpendicular and parallel to grain of main and side member. First, through the dowel bearing test, the dowel bearing strength was evaluated and through the bolt bending tests, the bolt bending strength was evaluated. And then experiments for the connection were performed. Obtained results from experiments were compared with calculated values by EYM and analyzed. Strength of double shear bolted connections in Korean Larch was similar or higher than calculated value by EYM. Especially when the side member was made by the sawn lumber, it was similar to the calculated value. In failure mode, the mode was effected by the knot and the dry defect. In the thin main member, it was shown mode I and as the thickness of the main member was thicker, it was changed into mode III.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.291-297
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• 2009

Relaxation of high strength bolts was investigated. Block type and splice type specimens were fabricated with different types of bolts and different clamping lengths. Bolts were tightened to the specified torque. Clamping forces were measured through strain gauges installed on the shafts of bolts, while specimens were kept in a constant temperature and humidity. In all cases, ratio of clamping force reduction is less than 10%. Test results of different types of specimens and bolts and different clamping lengths were compared each other by using a simple model, which is suggested in this study for the estimation of bolt relaxation. The suggested model shows reasonably good agreements with test results for all cases. No difference is found between F13T and F10T bolts, but Dacro coated bolts shows higher relaxation than black bolts by approx. 30%. And also the comparison of test results shows that ratios of bolt relaxation become larger as clamping lengths of bolt shorter and the number of faying surfaces greater.

• 건축구조
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• v.9 no.2
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• pp.40-41
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• 2002