• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2A
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• pp.165-170
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• 2008

New high strength bolts are required due to the development of the high strength steel, the ultra-thick steel plates, and the long-span bridge, though high strength bolts with tensile strength of 1,000 MPa are mainly used in construction site of every country. The high strength bolts are often subjected to a repeated tension-type of loading in which the fatigue failure is a major mode of failure. However, the theoretical and experimental study for the fatigue failure of tension bolt has not been well established in Korea. In this study, we performed a tensile fatigue test of F8T, F10T and F13T, F13T-N high strength bolts under tension. We proposed three fatigue strength specifications by performing 95% survival probability analysis for F8T, F10T, F13T, and F13T-N bolt under the $2{\times}10^6$ cycles of repeated loading. And the fatigue strength for the advanced screw thread shape bolt developed in this study are compared with the previous KS screw thread shape bolt.

• Journal of Korean Society of Steel Construction
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• v.28 no.6
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• pp.459-465
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• 2016

In this paper, it was performed the fatigue test to examine the effect of cyclic loading for the simple T-joint. Axial force of bolt by clamping and the change of the force by applied load were measured in the joint. And the bolt force, the failure mode and the fatigue strength under cyclic loading were investigated. The parameters of the tension joint were set to be the flange thickness and the diameter of bolt to a different stiffness of the joint in response to the combination. From the fatigue test, failure mode of tensile joints under cyclic loading could be evaluated using a static ultimate load of the specific failure mode in EC3. The fatigue strength of the tension joints was considerably higher than the fatigue strength of the EC3(36) that does not consider a lever action. However, the additional axial force by lever action occurs to an increase in the axial force of the bolt it requires a careful evaluation of the fatigue strength.

• Journal of Korean Society of Steel Construction
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• v.27 no.1
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• pp.53-61
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• 2015

The tension type joint is a mechanically very efficient connection method, as it directly uses the load capacity of base metal or high tension bolt, the reduction of the number of drilling hole and fastening and the fatigue resistance. It is applied to the joint of girder and cross beam, horizontal joints of towers, beam to column joints, the secondary member joints of deck floor ends, and brackets. In this paper, static load tests for the T-type tension joint were conducted to investigate the structural behavior of the joint. The parameters were bolt diameter, flange thickness, and the reduction of clamping force of the joint. The failure modes and load capacity of joints and the effects of flange thickness, bolt diameter and clamping force were investigated.

• Journal of Korean Society of Steel Construction
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• v.23 no.4
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• pp.493-501
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• 2011

The $45^{\circ}$cone failure theory has been used for concrete anchor bolt design, but the CCD (concrete capacity design) method was adopted as a new design method in 2000. The method was allowed to be used, however, only for anchors with a diameter of less than 50 mm and an embedment depth of less than 635 mm because it is based on the experiment results from medium-sized to small anchor bolts. Therefore, it is necessary to develop a rational concrete breakout capacity equation for medium-sized to large anchor bolts. In this study, tension tests on an M56 cast-in-place single anchor bolt with an effective embedment depth of 400-450 mm were carried out for the five test specimens. Based on the test results together with the other recent test results, the applicability of the concrete breakout capacity equation in the current design code to the large to medium-sized anchor bolts with an embedment depth of 280-1,200 mm was estimated.

• Journal of the Korea Concrete Institute
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• v.13 no.4
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• pp.321-328
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• 2001

This paper presents the tensile behavior of stud connections installed between reinforced concrete and steel members. Eight specimens are tested to verify the factors influencing the tensile behavior of the connection. Major variables considered in the test are the reinforcement ratios of concrete member and connection details. Test results indicate that the reinforcing bars near stud bolts contribute to the increase of the tensile strength of the member as well as to the reduction of brittle failure. It is shown that C-type or U-type connection has relatively high ductility. From the evaluation on the tensile strength of test results including those of peformed by previous researchers, it was shown CCD (Concrete Capacity Design) method overestimated the strength. In this paper, the reduction factor of 0.75 ø instead of ø is suggested for design purpose of the stud connection.

• Tunnel and Underground Space
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• v.21 no.5
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• pp.377-385
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• 2011

In order to prove the applicability of rock bolts with compressible spacers, laboratory model tests and large scale model tests were conducted. Laboratory model tests were performed in various distance of compressible spacers to determine the optimal distance of compressible spacers. The optimal distance of compressible spacers was found that is 1/4 of rock bolts unit length. Large scale model tests that the size was 0.6 m (diameter) ${\times}$ 4.45 m (length) were conducted. Test results showed that pull out resistance could be increased up to 15% larger than that of unused case by using compressible spacers.

• Journal of Korean Society of Steel Construction
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• v.26 no.6
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• pp.617-626
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• 2014

In this paper, experiments for the evaluation of tensile strength of steel plate with bolt hole and bearing strength of bolted connection were performed, where bolt holes were punched by drilling and oxygen torch, respectively. For the tensile tests, drilled and oxygen torch punched steel plate specimens of 10mm and 15mm thickness were made from structural angles and H-shapes, respectively. For the bearing strength evaluation, test specimens were fabricated with base plates and splice plates those were also punched by drilling and oxygen torch, respectively. The Vicker's hardness were measured around the bolt hole to investigate material property change due to heat effect by oxygen torch cut. Numerical analysis was also performed to investigate the bearing strength of bolted joints due to the increase of hardness around the bolt hole by oxygen torch cut.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.1
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• pp.225-232
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• 2005

The paper presented results of the strength distributions and tension failure behaviors of splices subjected to tension forces. The bolting patterns in the tension splices are regular and staggered patterns in the research. The finite element analyses were carried out to examine the experimental results and evaluated the stress distribution patterns. The yield stresses, maximum tension stresses, stress distribution ratios, and effective net areas were analyzed through the tension experiments.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.620-627
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• 2006

강재기둥으로부터 전달되어 내려오는 모멘트 하중에 의한 베이스판의 변형을 고려한 앵커볼트의 설계방법에 대해 소개하였다. 기둥-베이스판 접합부의 설계를 위해 간략해석 모델 (Simple Beam Model) 이 개발되었으며 인장력과 모멘트 하중에 동시에 저항하는 앵커볼트의 설계를 위해 국부 메카니즘 개념이 도입되었다. 제안된 새로운 설계법을 적용하여 앵커볼트와 베이스판 사이의 최대지압력을 계산할 수 있었으며 이를 바탕으로 앵커볼트의 사이즈를 결정할 수 있었다. 본 논문에서는 상기 간략히 소개된 앵커볼트 설계법을 보다 상세히 기술하였다.

• Journal of Korean Society of Steel Construction
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• v.24 no.5
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• pp.605-612
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• 2012

A tension member that has a high-strength bolt fastened to a standard bolt hole increases structural resistance but causes problems from workability or economic perspectives. In this research, a total of 28 samples that have standard and over bolt holes as the tension member's high-strength bolted connection were made and a tension test was conducted. The change of strength of the connection has been confirmed by comparing the tension load of standard and over bolt hole samples obtained from the test results with the design strength due to net section and end distance. Samples made with over bolt holes had a lighter tension load than that of samples made with standard bolt holes, exceeded the design strength of present design standards, and although decrease in strength was inevitable due to the over bolt hole, their safety was satisfactory.