• Steel and Composite Structures
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• v.1 no.2
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• pp.245-268
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• 2001

The analysis of steel-concrete composite joints presents some particular aspects that increase their complexity when compared to bare steel joints. In particular, the influence of slab reinforcement and column concrete encasement clearly change the moment-rotation response of the joint. Starting from an energy approach developed in the context of steel joints, an extension to composite joints is presented in this paper that is able to provide closed-form analytical solutions. In addition, the possibility of tri-linear or non-linear component behaviour is also incorporated in the model, enabling adequate treatment of the influence of cracked concrete in tension and the softening response of the column web in compression. This methodology is validated through comparison with experimental tests carried out at the University of Coimbra.

• Structural Engineering and Mechanics
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• v.40 no.6
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• pp.867-883
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• 2011

Six reinforced concrete beam-column joint specimens were constructed and tested under reverse cyclic loading to failure. The six specimens were divided into three groups, each group representing a different joint design. The main objectives of this study are to investigate the response of joints with three different design, reinforcement detailing and beam strengths, and to evaluate and compare the responses of beam-column joints reinforced with traditional steel rebar and a recently proposed steel reinforcement called prefabricated cage system (PCS). Each of the three test specimen designs included equivalent amount of steel reinforcement and had virtually identical details. The results of the research show that the PCS reinforced joints had a slightly higher strength and significantly larger deformation capacity than the equivalent rebar reinforced joints.

• Structural Engineering and Mechanics
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• v.40 no.6
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• pp.801-811
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• 2011

A new experimental technique was developed on the plate-inserted welded tubular joints of spatial grid structures. In the experimental technique, a microcomputer controlling instrument of moire intervention (MCIMI) was adopted. A test was designed on the plate-inserted welded tubular joints of spatial grid structures to show the effectiveness of the MCIMI technique. Both traditional electrical measuring technique and MCIMI technique were employed in the test. The test results showed that the MCIMI technique was feasible in the case of the complicated tests on steel structures. The MCIMI technique not only implemented the limitation of traditional electrical measuring technique, but also improved the accuracy of the test. According to the test results, we further examined the plate-inserted welded tubular joints in the cable-stayed spatial grids of the Binhai International Convention & Exhibition in Tianjin, China. The analysis showed the joints are safely designed with adequate conservatism. The research provided a new application of MCIMI in the field of large-scale structure engineering.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.1-6
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• 1990

Joints are provided in cement concrete pavements to control transverse and longitudinal cracking that occur due to restrained deformations caused by moisture and temperature variations in the slab. But the construction of joints reduces the load-carrying capacity of the pavement at the joints, and pavements have beem deteriorated by cracks at the slab edges along the joints due to traffic loads. Therefore, it is important to analyze the behavior of joints accurately in the design of cement concrete pavements. In this study, the mechanical behavior of cement concrete pavement slabs is analyzed by the plate-finite element model, and Winkler foundation model is adopted to analyze the subgrades. The load transfer mechanism of joints are composed of dowel action, aggregate interlocking, and tied-key action, and the analytical program is developed using these joint models.

• Steel and Composite Structures
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• v.25 no.1
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• pp.45-55
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• 2017

Stainless steel exhibits high ductility and strain hardening capacity in comparison with carbon steel widely used in constructions. To analyze the particular behaviour of stainless steel cover-plate joints, an experimental study was conducted. It showed large ductility and complex failure modes of the joints. A non-linear finite element model was developed to predict the main parameters influencing the behaviour of these joints. The results of this deterministic model allow us to built a meta-model by using the quadratic response surface method, in order to allow for efficient reliability analysis. This analysis is then applied to the assessment of design formulae in the currently used codes of practice. The reliability analysis has shown that the stainless steel joint design according to Eurocodes leads to much lower failure probabilities than the Eurocodes target reliability for carbon steel, which incites revising the resisting model evaluation and consequently reducing stainless steel joint costs. This approach can be used as a basis to evaluate a wide range of steel joints involving complex failure modes, particularly bearing failure.

• Proceedings of the KWS Conference
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• 2001.10a
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• pp.281-284
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• 2001

Fatigue behaviour of eight different hollow section T-joints was investigated experimentally using scaled steel models. The joints had circular brace members and rectangular chords (CRHS). Hot spot stresses and the stress concentration factors (SCFs) were determined experimentally. Fatigue testing was carried out under constant amplitude loading in air. The experimental SCF values for CRHS joints were found to be between those of circular-to-circular (CCHS) and rectangular-to-rectangular (RRHS) hollow section joints. The fatigue strength referred to experimental hot spot stress was in reasonably good agreement with current fatigue design codes for tubular joints.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.4
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• pp.119-127
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• 2002

This paper presents a study of the behaviour of bolted circular flange joints in tubular structures. In the tests on nine circular flange joints, different tension forces was applied to the joints and bolt strains, displacements and strains in the joints have been measured. Bolt strain, contact force(prying force) between flanges and stress distribution in a joint have been studied. Different methods used for the design of circular flange joints are described.

• Journal of the Korean earth science society
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• v.37 no.6
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• pp.332-345
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• 2016

The columnar joints in Goheung are developed in three places of Yuju-san area, Palyeong-san and Yongbawi area. Vertical and fan-shaped columnar joints which have maximum width 100 m and maximum heigh 50 m are developed in the Yuju-san area Columnar joints are developed next to the road near the the Yuju-san and along the coast of Jijuk-do. Thick columnar joints of maximum width 1m are developed in the Paryeong-san area. Horizontal columnar joints of maximum width 50 cm at length of polygon side are developed on dyke in the Yongbawi area. The columnar joints show high rate of rectangles and pentagons in the number of polygons. The length of polygon side of columnar joints in study area ranges from 10 to 100 cm, and 20 cm among the range appears in high frequency. Columnar joints are developed vertically to the ground from the cooling surface in Yuju-san and Palyeong-san area. Columnar joints in Yongbawi area are developed vertically to the contact of country rocks. As a result, the columnar joints began cooling from the country rock contact. And columnar joints are developed vertically to contact surface. The rocks in columnar joints is rhyolitic welded tuff in Yuju-san and Palyeong-san area, dacite in Yongbawi area. In the acid volcanic rocks flow structure well developed. The white phenocryst mineral about 2 mm size by eye, is usually feldspar, and includes some quartz. The rate of $SiO_2$ is 70wt.% or more. It is the last stage of differentiation to calc-alkaline series. The columnar joints of the Yuju-san area are expected to be distributed along a band that extends to about 1km east of the stone pit.

• Steel and Composite Structures
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• v.3 no.2
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• pp.123-140
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• 2003

The importance of the research on moment-resistant properties of unstiffened tubular joints and the research background are introduced. The performed experimental research on the bending rigidity and capacity of the joints is reported. The emphasis is put on the discussion of the flexural behavior of the joints including sets of geometrical parameters of the joints and several loading combinations. Procedures and results of loading tests on four full size joints in planar KK and X configuration are described in details at first. Mechanical models are proposed to analyze the joint specimens. Three-dimensional nonlinear FE models are established and verified with the experimental results. By comparing the experimental data with the results of the analysis, it is reported reasonable to carry out the structural analysis under the assumption that the joint is fully rigidly connected, and their bending capacities can assure the strength of the members connected under certain limitation. Furthermore, a parametric formula for inplane bengding rigidity of T and Y type tubular joints is proposed on the basis of FE calculation and regression analysis. Compared with test results, it is shown that the parametric formula developed in this paper has good applicability.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.327-336
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• 1991

The purpose of this study was to evaluate the validity among the clinical, transcraial radiographic and MRI diagnosis in internal derangement of the temporomandibular joint. Fourty two temporomandibular joints were assessed in twenty one patients who visited the dental department of Chonnam National University Hospital with the complaint of temporomandibular disorder from Oct. 1990 to Oct. 1991. The results were as follows: 1. In the clinically symptomatic 29 TMJs, 26 (89.7%) joints reveal disc displacement and 3 (10.3%) joints reveal normal disc position on MRI. The sensitivity of clinical diagnosis was 0.77, and the specificity was 0.63. 2. In the normal 22 TMJs on the trans cranial radiographic finding, 16 (72.7%) joints reveal disc displacement, and 6 (27.3%) joints reveal normal disc position on MRI. In the abnormal 20 TMJs on the transcranial radiographic finding, 18 (90%) joints reveal disc displacement, and 2 (10%) joints reveal normal disc position on MRI. The sensitivity of trans cranial radio- graph was 0.53, and the specificity was 0.75.