• Computers and Concrete
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• v.32 no.4
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• pp.411-423
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• 2023

The rapid development of road transport has increased the number of bridges that require widening. A critical issue in the construction of bridge widening is the influence of vibrations of the old bridge on the casting of wet joint concrete between the old and new bridges owing to the running traffic. Typically, the bridge is closed to traffic during the pouring of wet joint concrete, which negatively affects the existing transportation network. In this study, a newly developed microscopic traffic load modeling approach and the vehicle-bridge interaction theory are incorporated to develop a refined numerical framework for the analysis of random traffic-bridge coupled dynamics. This framework was used to investigate traffic-induced vibrations at the wet joint of a widened bridge. Based on an experimental study on the vibration resistance of wet joint concrete, traffic control strategies were proposed to ensure the construction performance of cast-in-site wet joint concrete under random traffic without interruption. The results show that the vibration displacement and frequency of the old bridge, estimated by the proposed framework, were comparable with those obtained from field measurements. Based on the target peak particle velocity and vibration amplitude of the wet joint concrete, it was found that traffic control measures, such as limiting vehicle gross weight and limiting traffic volume by closing an additional traffic lane, could ensure the construction performance of the wet joint concrete.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.255-266
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• 2014

This paper investigates the seismic performance of T-shaped PC walls with a new vertical connections and wet cast joint. The load-displacement relationship, strength, ductility, failure mechanism, and deformation capacity of the T-shaped PC walls subjected to cyclic loading are verified. Test parameter is diagonal reinforcement of both flange and web wall panels to transfer shear strength. The longitudinal reinforcing steel bars placed edges of walls yield first and the ultimate deformation is terminated due to premature failure of connections. And diagonal reinforcements for shear transfer in walls are effective to restrain the wall crack. The strength and displacement obtained by the cross section analysis were very similar to the experimental data.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.234-238
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• 1999

This study suggests the design of the functionally gradient composite, [0/90/0/core]$_s$ cross-ply laminate, to prevent stress concentration induced from the difference of rigidity between the bone and the artificial hip joint and to reinforce the wear property of the surface and the expectation of their mechanical properties. First, the four-point bending test is done about wet bones and dry bones to know the mechanical properties of the cortical bones. In result, the wet bone shows the viscoelastic behavior and the dry bone shows the elastic behavior. Moreover, we expect the properties of the proposed gradient composites as a function of carbon fiber volume fraction in each layer to apply Halpin-Tsai equation, CLPT(classical laminate plate theory), and Bernoulli beam theory etc. and decide the thickness ratio of each lamina in order to match Young's modulus of the anisotropic cortical bone with the proposed gradient composites.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.725-730
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• 1998

In the nuclear power plant, steel or polymer liner plates are adopted to prohibit inner concrete surface contacting with gas or liquid materials. If there is an accident, the plate will be damaged, and concrete shall have final responsibility to safety requirements. In this paper, an experimental research was carried out to investigate the effects of construction joint and wet and loading condition on the permeability of concrete. The test results showed that leakage rate is decreased much more at the following cases than the others : (a)wet condition, (b)without a construction joint case, and (c)case subjected to external loads. It was noted that more reinforcement is required at the latter case.

• Corrosion Science and Technology
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• v.4 no.3
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• pp.95-99
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• 2005

Wheel test and potentiodynamic polarization methods were used to evaluate the relative effectiveness of some hydrogen sulfide corrosion inhibitors for the wet gas pipeline API 5L grade X 65 steel. Five commercially corrosion inhibitors have been studied in the deoxygenated produced water solutions containing 10 ppm and 100 ppm of hydrogen sulfide. Based on the experiment results the steel corrosion inhibition mechanism in discussed and two most effective corrosion inhibitors are selected.

• Journal of Ship and Ocean Technology
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• v.1 no.1
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• pp.26-34
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• 1997

Under water wet welding is an economically alternative for the repair of offshore structures. In this paper investigations on the fatigue strength of a wet welded pipe structural member have been reported. For the connection a special sleeve patch design has been developed. The joint was fatigue tested. The evaluation of the test was carried out by means of the hot-spot approach with regard to several extrapolation rules of the hot-spot stress. Obtained results have been compared to actual classfication rules and recommendations.

• Composites Research
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• v.22 no.5
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• pp.30-36
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• 2009

The failure strengths and modes in carbon fiber reinforced polymeric composites, with two serial bolt-fastened composite joints, were investigated to evaluate the typical joint configurations of composite components. The parametric studies were performed experimentally at room temperature dry and elevated temperature wet, $82.2^{\circ}C$ on several different laminate configurations. Based on the experimental data presented, two basic load-displacements curves are observed. Each failure mode has the characteristic curve. It is showed that the bearing failure mode occurs in elevated temperature wet condition. It is analysed that the strength of bearing failure mode is not highly depending on the effective modulus of specimen. The failure strength at elevated temperature wet is decreased by the cause of interfacial deterioration between fiber and matrix with moisture absorption.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.11
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• pp.1115-1122
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• 2010

The main objective of this study is to experimentally investigate the effect of adhesive thickness and environmental conditions on the failure and strength of sandwich-to-laminate bonded joints. Three different adhesive thicknesses (t=0.2, 2 and 4 mm) and two different environmental conditions were considered. Environmental conditions include the RTD(room temperature and dry condition) and ETW(elevated temperature and wet condition). Test results show as the adhesive thickness increases from 0.2 mm to 2 and 4 mm, the joint strength decreases 16 and 30%, respectively. Regarding the effect of environmental conditions, except for one case, the joint strength in the ETW conditions turned out to be 12% higher than those in the RTD conditions. In the joints with adhesive thickness of 0.2 mm, remarkable difference from RTD condition was not found.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.33 no.3
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• pp.125-137
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• 2020

Objectives : Charcot neuroarthropathy(CN) is condition characterized by a progressive joint deformation with sensorial and autonomic neuropathy. This study is to report a case of CN improved by Korean medical treatment. Methods : The patient's left foot with CN was treated by Shudihuangkushen-tang, Haifu-san wet dressing, acupuncture and herbal acupuncture. We evaluated the progress by laboratory investigation, radiograph and photograph comparison, visual analogue scale(VAS) of edema and pain sensation. Results : After treatment, VAS score of edema dropped from 6 to 1, of pain sensation slightly improved from 0 to 1. Average blood sugar level decreased and rebounded, but Hemoglobin A1c level improved from 9.5% to 7.7%. Improvement of the left foot was recognized from the radiograph and photograph comparison. Conclusions : This study suggests Korean medicine is effective in treating CN, especially using Shudihuangkushen-tang, Haifu-san wet dressing.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.370-373
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• 2006

Lastly, the problem of filling occurs in the process of concealed joint of adjacent components and was seen in joints between the structure and an electrical or mechanical device. Therefore, the dry processing which replaces wet joint was seen in joints between the structure and a door, ones between the structure and a finishing materials, ones between a gypsum board and electrical device, and ones between a water pipe and a tile finishing. And a process of separating the area of jointed parts in order to eliminate the problem of overlap was seen in joints between a door and a finishing material and ones between a gypsum board on the ceiling and a light. Lastly, an analysis of a process of exposing concealed parts indicated that the problem of filling could be applied to joints between the structure and an electrical or mechanical device and ones between a finishing material and a mechanical device. This study sought out methods to apply Environment Friendly Multi Housing Remodeling that allow easy remodeling as part of environment- preserving policies. It also contains basic data useful to implement long-life houses in the future by presenting a comprehensive design standard for them