• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.615-618
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• 2011

최근 건설공사에서 많은 물량이 투입되는 기초구조의 자재비 및 원가절감을 위해 여러 가지 기초구조시스템이 개발되고 있으나, 보편적으로 현장에 적용하기에는 다소 무리가 있는 것으로 지적받고 있다. 본 연구는 강판을 ㄷ자형으로 절곡한 기초전단보강시스템을 개발하기 위한 해석적 연구의 일환으로 진행되었다. 현행 전단머리 보강식에서는 기초판에 대한 전단내력 산정을 위한 기준식이 마련되어 있지 않으며 플랫플레이트 슬래브의 기준식에 따르도록 되어져있다. 그러나 기초판은 지반에 지지되는 구조물로 플랫플레이트 슬래브와는 경계조건이 다르다. 따라서 본 연구에서는 지반에 지지된 경우와 플랫플레이트 슬래브와 같이 모멘트 제로지점을 단순지지한 형태로 기초구조물을 모델링하여 해석을 실시하였다. 해석프로그램은 유한 요소기법이 적용된 ABAQUS를 사용하여 두 지지조건의 차이가 구조물에 미치는 영향을 비교분석하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.847-850
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• 2008

In simply supported concrete beams with concentrated load, there is arch action that the internal lever arm length varies through shear span. Recently shear analysis model considering this effect has been developed, but the analysis algorithm is so complicated. Moreover, the variation of internal lever arm length is not considered on the shear compatibility condition. In this study, the shear analysis model is developed more simply and the variation of internal lever arm length is considered on the shear compatibility condition. From these modifications, an actual shear behavior of RC beams subjected to concentrated load could be expected from the results of the proposed analysis model.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1521-1528
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• 2011

We studied the material properties for reliability improvement in finite element analysis results for a nitrile butadiene rubber hub-bearing seal and for a carbon-filled rubber mount used in a vehicle. It was difficult to measure the material properties of hundreds of types of rubber for the mount design. Thus, we suggested that the engineering stressstrain relations from pure shear test data could be synthesized by using simple tension data and Poisson's ratio. We defined Poisson's ratio by using a function of principal stretches to synthesize the stress-strain relations for a pure shear test. A transformation of the pure shear data was applied to the experimental values to obtain the predicted results when the strain approaches 100%. In the finite element analysis for the contact force of a hub-bearing seal, the strain results that used the transformation of the pure shear data and simple tension data almost corresponded to the experimental values. Ogden constants were used to analyze.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.2
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• pp.213-220
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• 2016

The needs for the utilization of space in the urban ara due to the increasing population and traffic volume. A Double-deck tunnel can be an appropriate solution. Geosynthetics are inevitably installed between ground and tunnel lining, therefore, geosynthetic-soil interface is also comprises. Dynamic shear behavior of geosynthetic-soil interface affects the dynamic behavior of tunnel, and experimental study is required since the behavior is very complicated. In this study, chemical factors such as acid and basic element in the groundwater and temperature are considered in the laboratory test. Multi-purpose Interface Apparatus(M-PIA) is utilized and submerging periods are 60 and 960 days. Consequently, dynamic shear degradation of geosynthetic-soil interface considering chemical and thermal factors are verified.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.413-423
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• 1991

Multiaxial loading by combinations of tension-torsion-internal pressure have been applied to the thins-walled tubular specimens prepared from cold drawn tubes of SAE 1020 steel. Prior to the multiaxial loading, each specimen has been twisted to different shear strains. Uniaxial tensile yield stresses measured at different angles to the tube axis clearly show that the initial orthotropic symmetry is maintained during twisting. The orthotropy axes are observed to rotate with shear strains. The plane stress yield locus measured for each twisted specimens show that yield surface shape does not remain similar during twisting and thus anisotropic work hardening is not a function of only plastic work.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.567-571
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• 1997

Recently, automobile industry has led to increasing use of aluminum alloy for weight reduction. Automobile made of aluminum alloy can be given lighter, stronger and a harder surface by anodizing than one made of steel-alloy. In this paper, we investigate the influence of lap length, adherend thickness and adhesive thickness on adhesive strength of single-lap adhesive joints by conducting tensile-shear tests. Single-lap adhesive joints of aluminum was calculated using joint factor by using adhesive length, adherend thickness of specimen.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1A
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• pp.55-64
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• 2012

Experimental investigation on the structural behavior of steel fiber-reinforced ultra high performance concrete (UHPC) beams subjected to shear are presented. Six tests carried out on simply supported I-beams under concentrated loads are presented. The parameters varied were the volume fraction of the fibers (1.0, 1.5 and 2.0%) and shear span-effective depth ratio (2.5, 3.4). The test results indicated that ultimate shear strength increased with increasing fiber volume, and that ultimate shear strength decreased with increasing shear span-effective depth ratio. In addition, applicability of predictive equations for evaluating the ultimate shear strength of steel fiber-reinforced UHPC beams are estimated based on the test results. The comparison between computed values and the experimentally observed values are shown to validate the proposed theoretical equations. It is found that predictions by using AFGC and JSCE recommendations provide the most accurate estimates of shear strength of steel fiber-reinforced UHPC beams.

• Journal of the Korea Concrete Institute
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• v.29 no.1
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• pp.93-100
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• 2017

This study examined the one-way shear in concrete beam region and shear friction in joint region of a hybrid H-steel-reinforced concrete (HSRC) beam system with a simple ductile connection. One-way shear tests were conducted under overhanging beam system with a shear span-to-depth ratio of 1.6. Simple beams for shear friction were tested under two-point symmetrical top loads producing a clear shear span-to-depth ratio of 0.1. Test results showed that the dowel bars arranged in joint region insignificantly influence the propagation of shear cracks but enhances the shear strength of the HSRC beams by approximately 25%. The one-way shear strength and shear friction strength of HSRC beams can be conservatively evaluated using the design equations specified in ACI 318-14 and EC2 shear provisions.

• Magazine of the Korea Concrete Institute
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• v.23 no.1
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• pp.69-72
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• 2011

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.487-490
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• 2004

In this paper, we investigated the characteristics of initiation and propagation behavior for fatigue crack observed by changing various shapes of initial crack and magnitudes of loading in modified compact tension shear(CTS) specimen subjected to shear loading. In the low-loading condition, the secondary fatigue crack was created in the notch root due to friction on the pre-crack face grew to a main crack. In the high-loading condition, fatigue crack under shear loading propagated branching from the pre-crack tip. Influenced by the shear loading condition, fatigue crack propagation retardation appeared in the initial propagation region due to the reduction of crack driving force and friction on crack face. In both cases, however, fatigue cracks grew in tensile mode type. The propagation path of fatigue crack under the Mode II loading was 70 degree angle from the initial crack regardless of its shape and load magnitude.