• Journal of Korea Water Resources Association
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• v.44 no.7
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• pp.591-599
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• 2011

The rainfall intensity is a very essential factor which must be considered for the estimation of the time of concentration. The rainfall intensity, however, is not fully considered for the estimation of the time of concentration due to the complexity of the equation of rainfall intensity. To increase accuracy of the time of concentration, the rainfall intensity and return period were included in the derivation of the time of concentration equations in this study. The equation of rainfall intensity is Sherman type and the regional coefficients were estimated from the rainfall intensity readings on the probability rainfall maps published by Ministry of Construction and Transportation. For simple calculation of rainfall intensities, the contour maps were drawn that expresses coefficients of the Sherman type equation. By substituting the Sherman type equation of rainfall intensity in the equation of the time of concentration, a relatively simple equation with no repeated calculation has been derived. From the study results, in order to include the influence of the rainfall intensity for the estimation of the time of concentration, it is highly recommended that the Sherman type equation of rainfall intensity be used. When one knows a location in Korea and a return period, he can estimate the coefficients of the rainfall intensity equation and calculate the time of concentration considering the rainfall intensity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.183-190
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• 1993

It is desirable to utilize the result after studying the rainfall characteristics including the latest observation data in the districts for the sake of establishment of the more accurate plans for drainage or plans for hydraulic stuctures because the rainfall phenomena are different in their characteristics by regional groups and if we make a meteorological observation for a long period of time, the rainfall characteristics also change a great deal as compared with the preceding years. Therefore, we selected only the annual maximum rainfall from the self-recording rain gauge of the main rainfall observation station (Cheju, Sogwipo, Songsanpo) in the Cheju districts in the last twenty years, extracted the rainfall by actual measurement by the rainfall duration, and induced the optimal probable rainfall-intensity formulas by regional groups in the Cheju districts, taking advantage of the rainfall formulas being in wide use in general, that is, Talbot type, Sherman type, Japanese type, and new Semi-log type. As the result, the return periods at Cheju station appeared to be three years to five years and the optimal probable rainfall-intensity formula at Cheju station, Japanese type and outside the city, Talbot type; Sogwipo, Sherman type; Songsanpo, Talbot type respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.846-851
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• 2006

본 논문은 최근 발생한 집중호우와 이상강우를 고려하여 인천지역에서 사용중인 확률강우강도식에 대한 새로운 확률강우강도식을 제안하였으며, 기상청 자료를 이용하여 지속시간 10분${\sim}$24시간까지의 임의시간 연최대강우량을 산정하였다. 강우지속기간별 확률강우량을 추정하기 위하여 11개의 확률분포형을 적용하였으며 Chi-square 검정방법, Kolmogorov -Smirnov 검정방법, Cramer Von Mises 검정방법으로 적합도 검정과 함께 최근 강우에 대한 경향을 분석하고 실제 발생한 강우 중에서 최대 발생 강우량을 고려하여 적정분포인 GEV 분포를 확률 분포형으로 선정하였다. 확률강우강도식은 최소자승법을 사용하여 Talbot형, Sherman형, Japanese형, 통합형 Ⅰ 및 Ⅱ 형태로 산정하였고, 지역내 하수도 및 하천의 지속시간을 감안하여 확률강우강도식을 결정하였다. 또한 정확성을 고려하여 통합형 Ⅰ을 선택하였고 지속시간에 따른 강우강도식의 확률강우와 관측치를 감안한 강도식을 인천지역의 강우강도식으로 제안하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.259-259
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• 2012

범용토양유실공식(USLE)의 강우침식인자의 적절한 산정을 위해서는 각 독립강우사상의 30분 최대강우강도의 산정이 필수적이다. 이를 위해서는 조밀한 시간 간격으로 측정된 강우자료가 필요하나 자료습득의 용이성 문제 및 자료의 비연속성 문제 등이 있었다. 이를 해결하기 위해 박정환 등(2000)은 1시간 단위 자료로부터 기존에 개발된 Talbot형, Sherman형, Japanese형 강우강도경험식을 이용하여 30분 최대강우강도를 추정했다. 이후 이준학 등(2010)은 강우의 스케일 성질을 이용하여 속초지점의 2007년의 강우사상을 대상으로 1시간 최대강우강도로부터 30분 최대강우강도를 추정하는 방법을 제안했으며, 이준학 등(2011)은 대구지점의 1960년~1999년간 강우사상을 대상으로 고정시간 1시간 최대강우강도로부터 30분 최대강우강도를 추정할 수 있는 변환계수를 제안했다. 선행연구는 경험식을 이용했거나 연구대상을 특정지점에 국한 또는 1시간과 30분 최대강우강도의 일대일 변환관계에만 집중한 한계를 가지고 있다. 따라서 본 연구에서는 2000년~2010년의 AWS 분 단위 강우자료를 이용했고 도시, 내륙, 산간, 해안, 섬을 대표할 수 있는 전국 5개 지점에 대해 임의시간 최대강우강도로부터 30분 최대강우강도를 추정하는 관계곡선을 산정했다.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.2 s.5
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• pp.85-93
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• 2002

This paper is to derive the Intensity-Duration-Frequency Curve at Kong-Ju area after estimating probable rainfall depths using Rainfall Frequency Atlas of Korea. It has been suggested that the probable rainfall intensity formulas should be classified by short and long term basis in this area. The coefficients of determination of the probable rainfall intensity formulas are calculated as high as 0.9924 through 0.9971. Four types of rainfall intensity formulas such as Talbot type, Sherman type, Japanese type, General type are considered to determine the best type for the Kong-Ju area. Sherman type applied in this study can be determined as the representative probable rainfall intensity formula in the area. Therefore the rainfall intensity formulas for the selected return period in this study provide valuable insight into the estimation of the rainfall intensity. The developed Intensity-Duration-Frequency Curve can be used to provide a better hydraulic design at Kong-Ju area.

• Journal of Korea Water Resources Association
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• v.39 no.6 s.167
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• pp.521-531
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• 2006

The formula was proposed through the examination of probability rainfall intensity formula used in Incheon based upon recent occurrences of heavy rain and extraordinary storms. Random-time maximum annual rainfalls were estimated for durations from ten minutes to twenty-four hours from the data by Korea Meteorological Administration. Eleven types of probability distribution are considered to estimate probable rainfall depths for different storm durations at Incheon city. Three goodness-of-fit tests including Chi-square, Kolmogorov-Smirmov and framer Von Misses were used to analyze the tendency of recent rainfall. Considering maximum rainfall occurred, General Extreme Value(GEV) distribution was chosen as the appropriate probability distribution. Five types of probability rainfall formulas including Talbot type, Sherman type, Japanese type, unified type I and unified type II are considered to determine the best type for rainfall intensity at Incheon. The formula was determined considering the time of concentration of sewer system and river at Incheon city. Unified type I was chosen for its accuracy and was proposed to represent rainfall intensity of Incheon district.