• 한국도로학회:학술대회논문집
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• 2006.03a
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• pp.119-126
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• 2006

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.134.2-134.2
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• 2009

• 한국도로학회:학술대회논문집
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• 2008.10a
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• pp.175-182
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• 2008

• International Journal of Railway
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• v.2 no.1
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• pp.30-36
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• 2009

Crack and its damage of structure concrete in both FBS and TBS ballastless track are presented. The cause of concrete crack is analyzed. According to corresponding quantitative equation, effective technical measures to depression crack of concrete are put forward, at the same time the rationality of elastic ratio for HGT has been proved. At last, by the analysis of the characteristic of high-speed train, which are serving in the open air, bearing fatigue load, the short time for maintenance window and high speed of service, technical requirement for concrete repair material, repair technology and repair tools of ballastless track structure are presented.

• Steel and Composite Structures
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• v.18 no.4
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• pp.1045-1062
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• 2015

Concrete-filled circular t steel tubular joints (CFSTJs) in practice are frequently subjected to fluctuated loadings caused by wind, earthquake and so on. As fatigue crack is sensitive to such cyclic loadings, assessment on performance of CFSTJs with crack-like defect attracts more concerns because both high stress concentration at the brace/chord intersection and welding residual stresses along weld toe cause the materials in the region around the intersection to be more brittle. Once crack initiates and propagates along the weld toe, tri-axial stresses in high gradient around the crack front exist, which may bring brittle fracture failure. Additionally, the stiffness and the load carrying capacity of the CFSTJs with crack may decrease due to the weakened connection at the intersection. To study the behaviour of CFSTJs with initial crack, experimental tests have been carried out on three full-scale CFCST T-joints with same configuration. The three specimens include one uncracked joint and two corresponding cracked joints. Load-displacement and load-deformation curves, failure mode and crack propagation are obtained from the experiment measurement. According to the experimental results, it can be found that he load carrying capacity of the cracked joints is decreased by more than 10% compared with the uncracked joint. The effect of crack depth on the load carrying capacity of CFCST T-joints seems to be slight. The failure mode of the cracked CFCST T-joints represents as plastic yielding rather than brittle fracture through experimental observation.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.706-711
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• 1998

Structural tests of the PSC Beam bridge using high strength concrete, concrete compressive strength 700kg/$\textrm{cm}^2$, are conducted for the application including durability and serviceability of the bridge. Current design safety factors with respect to the jacking force and the service design load DB-24 are applied to the design of the bridge. Concrete compressive strength 700kg/$\textrm{cm}^2$, girder depth 2.3m, girder space 3.2m, span length 20m, and slab thickness 27cm are selected for the bridge test. The Bulb-Tee section of the girders is applied instead of I section because it is well known more stable to the longer span(40m). Static load test(4 beams) with composite and non-composite section, and fatigue load test(1 beams) with composite section are conducted. Crack moment, ultimate load, deflections with load steps, and strains of the beam section for those bridges are investigated. The structural test results of the bridges showed a good performance for a safety and a serviceability.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.1-8
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• 1991

Recently the use of steel fibers has been increased in flexural members and columns of concrete structures subjected to cyclic loadings; such as bridge decks, highway roads, runway of airport, buildings, etc.. However only a few experimental tests have been carried out under fatigue loading. In the present study, the reinforced concrete beams with 1% and 2% steel fiber volume fraction are investigated with and without stirrups. It has been found that in fatigue tests, the failure of the beam is usually due to breaking of fibers rather than fiber pull-out. A comparison of experiments and numerical analysis using the nonlinear F.E.M. program (ADINA) is also presented herein.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.6
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• pp.138-144
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• 2013

This study is for quality standard establishment of urethane waterproofing membrane method which is mostly applied to waterproofing method for underground parking lot and rooftop. The experiments were carried out on color differences, membrane thickness, tensile property by curing period of liquid urethane before placing protective concrete, and resistance of crack movement according to different substrate surface and reinforcement of non-woven fabric. As a result of experiments, it was found that color differences is increase, membrane thickness is thick, tensile property is low as concrete placing period is shorter. In the fatigue property, membrane thickness of 3 mm was not broken, but 1~2 mm was broken and in the case of the membrane reinforced with non-woven fabric was more stable comparatively non-reinforcement one.

• 한국도로학회:학술대회논문집
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• 2011.03a
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• pp.277-284
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• 2011

• The Journal of Internal Korean Medicine
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• v.29 no.1
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• pp.219-230
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• 2008

Objectives : Consumption is a chronic wasting disease, in oriental medicine concept. Fatigue is a common symptom experienced by many people who have consumption. However, there has been little study about the relationship between consumption and fatigue in the Oriental medicine. For this reason, we attempted to investigate the present status of fatigue of outpatients, and its relation with consumption index, public health practice index, Chalder fatigue scale and Subjective Symptoms of Fatigue Test. Methods : The subjects were 149 outpatients who complain fatigue between Nov. 1, 2006 and Oct. 31, 2007. We measured degree of consumption by consumption index. We measured degree of fatigue by Chalder fatigue scale and Subjective Symptoms of Fatigue Test. Public health practice were investigated by "Breslow's 7 health practice". Results : Studies have shown that a group who disregard public health practices have higher numerical value, in part of $q\grave{i}-x\bar{u}$, $xu\grave{e}-x\bar{u}$, and Physical symptoms than a group more concerned with public health practice. A group who has fatigue for a period over 6 months are more likely to be $q\grave{i}-x\bar{u}$, $y\bar{i}n-x\bar{u}$, Chalder fatigue scale, neuro-sensory symptoms than a group fatigued for less than 6 months. Among the subjects, 81 (55.5%) were considered as 'fatigue patients' by the Chalder scale. Chalder fatigue scale, according to the Subjective Symptoms of Fatigue Test, consumption also, The more increase of Subjective symptoms of fatigue test, the more of consumption scale. Conclusions : This study has shown that there is a link between consumption and fatigue. Moreover, oriental medicine's consumption is more concrete than fatigue scale, so consumption index will have wide application to the study of fatigue.