Based on the meteorological and geographic information data, with statistical method and the FloodArea model, the extreme daily rainfall of the 100-year return period in Hunhe River basin was established, through the ...Based on the meteorological and geographic information data, with statistical method and the FloodArea model, the extreme daily rainfall of the 100-year return period in Hunhe River basin was established, through the simulation of rainstorm and flood disaster, characteristics of flood depth in warning spot Cangshi village in the upstream of the river were analysed, and possible effect on community economy was also evaluated. Results showed that, the precipitation of 100-year return period occurred, the flood depth has been below 1.0 meter in the most areas of Hunhe River basin, the depth was between 1.0 meter and 2.5 meters in the part areas of Hunhe River basin, and the flood depth has been exceed 2.5 meters in a small part of Hunhe River basin. After the beginning of precipitation, the flood was concentrated in the upper reaches of the river. With the accumulation of precipitation and the passage of time, the flood pools into midstream and downstream. Precipitation lasted for 24 hours, the warning spot was flooded in the beginning of precipitation. With the accumulation of precipitation, water level of the river increases gradually. The depth of warning spot has passed 1.0 meter at the 07 time of the whole process, and the maximum value of flood depth at warning spot was 1.083 meters that occurred at the 19 time. The flood depth of warning spot decreased gradually after the precipitation stopping, and the depth has been below 0.2 meters, the flood of upstream ended. Up to the end of the upstream flood process, in the whole river, about one million five hundred and sixty thousand people were affected by flooding, and thirty-eight billion and two hundred million RMB of gross domestic product were lost, in addition, dry land and paddy field were affected greatly, but woodland and grassland were less affected.展开更多
Surat city, the commercial capital of Gujarat state, India is situated at latitude 21°06’ to 21°15’ N and longitude 72°45' to 72°54'E on the bank of river Tapi and is affected by flood on...Surat city, the commercial capital of Gujarat state, India is situated at latitude 21°06’ to 21°15’ N and longitude 72°45' to 72°54'E on the bank of river Tapi and is affected by flood once in every five years since last hundred years. Present study describes the application of HEC-RAS model with integration of GIS for delineation of flood plain. Digital Elevation Model (DEM) of Surat city is used as main input for flood inundation mapping. River section near Nehru Bridge is used as sample case to simulate flood flow. Discharges equal to food return period for 25 and 32 (worst flood year) have been used for investigation of flood scenario. Outcome of the research clearly indicates that most of the area of the Surat city is submerged for a depth of 2.5 to 4.0 m when the discharge released from Ukai dam equals to return period of 32 years (25768.09 Cumecs).展开更多
以北海铁山港入海明渠为例,基于北海站1967年—2008年实测连续42 a 24 h降雨量资料和与其相应石头埠潮位站潮位资料,采用G-H Copula函数构建以皮尔逊Ⅲ型分布为最优边缘分布的雨量、潮位联合分布模型,同时在传统的OR和AND重现期基础上,...以北海铁山港入海明渠为例,基于北海站1967年—2008年实测连续42 a 24 h降雨量资料和与其相应石头埠潮位站潮位资料,采用G-H Copula函数构建以皮尔逊Ⅲ型分布为最优边缘分布的雨量、潮位联合分布模型,同时在传统的OR和AND重现期基础上,引用防洪重现期概念,发现防洪重现期与OR和AND重现期相比更能避免最可能设计组合值设计标准出现偏高或偏低的情况。此外,基于蒙特卡罗法对雨、潮组合进行不确定性分析。结果表明:雨、潮最可能组合联合设计值95%置信区间随着重现期水平的递减和样本容量的增加而逐渐减小。以防洪重现期为设计标准推求得到的明渠设计水深的95%置信区间宽度和标准差均小于OR重现期,说明防洪重现期可以有效减少明渠设计水深的不确定性。展开更多
文摘Based on the meteorological and geographic information data, with statistical method and the FloodArea model, the extreme daily rainfall of the 100-year return period in Hunhe River basin was established, through the simulation of rainstorm and flood disaster, characteristics of flood depth in warning spot Cangshi village in the upstream of the river were analysed, and possible effect on community economy was also evaluated. Results showed that, the precipitation of 100-year return period occurred, the flood depth has been below 1.0 meter in the most areas of Hunhe River basin, the depth was between 1.0 meter and 2.5 meters in the part areas of Hunhe River basin, and the flood depth has been exceed 2.5 meters in a small part of Hunhe River basin. After the beginning of precipitation, the flood was concentrated in the upper reaches of the river. With the accumulation of precipitation and the passage of time, the flood pools into midstream and downstream. Precipitation lasted for 24 hours, the warning spot was flooded in the beginning of precipitation. With the accumulation of precipitation, water level of the river increases gradually. The depth of warning spot has passed 1.0 meter at the 07 time of the whole process, and the maximum value of flood depth at warning spot was 1.083 meters that occurred at the 19 time. The flood depth of warning spot decreased gradually after the precipitation stopping, and the depth has been below 0.2 meters, the flood of upstream ended. Up to the end of the upstream flood process, in the whole river, about one million five hundred and sixty thousand people were affected by flooding, and thirty-eight billion and two hundred million RMB of gross domestic product were lost, in addition, dry land and paddy field were affected greatly, but woodland and grassland were less affected.
文摘Surat city, the commercial capital of Gujarat state, India is situated at latitude 21°06’ to 21°15’ N and longitude 72°45' to 72°54'E on the bank of river Tapi and is affected by flood once in every five years since last hundred years. Present study describes the application of HEC-RAS model with integration of GIS for delineation of flood plain. Digital Elevation Model (DEM) of Surat city is used as main input for flood inundation mapping. River section near Nehru Bridge is used as sample case to simulate flood flow. Discharges equal to food return period for 25 and 32 (worst flood year) have been used for investigation of flood scenario. Outcome of the research clearly indicates that most of the area of the Surat city is submerged for a depth of 2.5 to 4.0 m when the discharge released from Ukai dam equals to return period of 32 years (25768.09 Cumecs).
文摘以北海铁山港入海明渠为例,基于北海站1967年—2008年实测连续42 a 24 h降雨量资料和与其相应石头埠潮位站潮位资料,采用G-H Copula函数构建以皮尔逊Ⅲ型分布为最优边缘分布的雨量、潮位联合分布模型,同时在传统的OR和AND重现期基础上,引用防洪重现期概念,发现防洪重现期与OR和AND重现期相比更能避免最可能设计组合值设计标准出现偏高或偏低的情况。此外,基于蒙特卡罗法对雨、潮组合进行不确定性分析。结果表明:雨、潮最可能组合联合设计值95%置信区间随着重现期水平的递减和样本容量的增加而逐渐减小。以防洪重现期为设计标准推求得到的明渠设计水深的95%置信区间宽度和标准差均小于OR重现期,说明防洪重现期可以有效减少明渠设计水深的不确定性。
