http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
오정호,피지현,최상현 한국복합신소재구조학회 2013 복합신소재구조학회 학술발표회 Vol.2013 No.04
In this paper, the effectiveness of the geogrid for reinforcing the trackbed is evaluated via numerical analysis. The finite element analysis is performed for the numerical analysis tool. In the study, the effect of the geogrid on the bearing strength of trackbed is investigated. Two different track systems including the conventional ballasted track and the asphalt underlayment track are adopted in the comparison study. The results show that the conventional ballasted track exhibited better effectiveness than the asphalt underlayment track. Also, better effectiveness of geogrid can be achieved by installing at one third depth of ballast layer from the bottom.
Establishment of Statewide Axle Load Spectra Data using Cluster Analysis
오정호,Lubinda F. Walubita,Joe Leidy 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.7
The role of traffic data in the Mechanistic-Empirical (M-E) pavement design is significantly crucial in assessment of pavement performance throughout the pavement design life. Providing a well-qualified traffic data for the M-E pavement design requires a huge effort with respect to collecting and analyzing the data. The Texas Department of Transportation (TxDOT) manages 30 Weighin- Motion (WIM) stations and provided classification and weight data used for this study. Evaluating the classification data first, vehicle classification distribution along with the percentage of trucks, average annual daily truck traffic, and monthly adjustment factor were established. Processing axle load data provided the number of axles per truck and axle load spectra for each of the traditional 13 vehicle classes. To develop statewide axle load spectra data, the cluster analysis was conducted using vehicle classification distribution and the Class 9 tandem axle load spectra data to provide traffic input data for the Texas M-E flexible pavement design program where the load spectra data are not available due to the absence of WIM station. As a result, six clusters for both variables were identified and a guideline was successfully established to use those clusters to generate axle load spectra inputs for a given set of truck traffic classification data.
Mechanistic-Empirical Guideline for Routine Overweight Truck Traffic Routes
오정호 한국재난정보학회 2013 한국재난정보학회 논문집 Vol.9 No.1
The main objective of this research is to develop the Mechanistic-Empirical (M-E) guidelines for evaluating the capacity of existing highways to sustain route overweight truck traffic over a specified performance period due to a growing concern on the impact of increasing overweight truck loads on highways. In this study, a two-stage framework was developed for this purpose. Level I procedure involves the use of pavement evaluation charts to identify the best possible route from among the alternatives considered and to determine what additional tests and analyses are needed as a screening tool. Level II involves the application of the Overweight Truck Route Analysis (OTRA) program to evaluate the structural adequacy of an existing route to carry routine overweight truck traffic over the specified performance period along with estimating asphalt concrete overlay thickness, if necessary.
Investigation of Geogrid-Reinforced Flexible Pavement Performance over Expansive Clay
오정호 한국방재학회 2011 한국방재학회논문집 Vol.11 No.6
Geogrid-reinforcement is often used in conjunction with unbound base layers (i.e., within the layer or as a subgrade/base interface layer) as a means for enhancing the performance of flexible pavements. In this study, a forensic investigation was conducted on a flexible pavement section in Texas to evaluate the influence of geogrid-reinforcement on pavement performance via field and laboratory experimental programs along with numerical analyses. It was evident that load bearing capacity of geogrid-reinforced segment tended to improve by exhibiting higher resilient moduli of unbound layers through dynamic cone penetrometer (DCP)test. Despite of obtaining high swelling and shrinkage potential of expansive subgrade soils due to moisture change from the laboratory test, field survey indicates that geogrid-reinforcement segment performs superior to the control segment along with less longitudinal cracks and lower international roughness index. In addition, numerical analyses validated the effectiveness of geogridreinforcement by yielding longer service lives with respect to rutting. This forensic investigation limitedly affirms that geogridreinforcement can effectively enhance pavement performance by mitigating movement of expansive clay.
오정호,박찬우,김성원,이강대 대한이비인후과학회 2012 대한이비인후과학회지 두경부외과학 Vol.55 No.12
Injection laryngoplasty is a simple and noninvasive method for treating unilateral vocal cord paralysis. Lately hyaluronic acid is widely used as injection material, because it is spontaneously resolved after few months and can be injected superficially compared to other materials. However, if hyaluronic acid is injected in the superficial layer of lamina propria (Reinke’s space), it can cause inflammation or granuloma, interrupt the vibration of the vocal cord and worsen the quality of voice. We here present a case of granuloma that occurred as a complication of injection laryngoplasty, where simple surgical method was employed to improve voice quality. Korean J Otorhinolaryngol-Head Neck Surg 2012;55:782-6