TY - GEN

T1 - Flood simulation considering probability of heavy rains and uncertainty of soil properties of earth-fill dams

AU - Nagao, Haruna

AU - Nishimura, Shin Ichi

AU - Fujisawa, Kazunori

AU - Shuku, Takayuki

PY - 2013/1/1

Y1 - 2013/1/1

N2 - Decrepit earth-fill dams ought to be improved in order to mitigate natural disasters. Since there is a recent demand for low-cost improvements, the development of a design method for optimum improvement work at a low cost is the final objective of this research. As a basic step, the risk to earth fills during heavy rains is evaluated here. The rainfall intensity and the variability of the numerous soil parameters of the earth-fills related to soil erosion are dealt with as probabilistic parameters. When the maximum overflow head on a spillway bed becomes greater than the design overflow head, overflow occurs. The peak overflow head, hp, is determined within 72 hours of the rainfall, and the various rainfall patterns are tested by the Monte Carlo method. Furthermore, the statistical values of the parameters for the soil erosion are assumed in this research, and the variability of the discharge hydrographs are derived from the values. The discharge hydrographs are applied for the flood simulation as input waves. The submerged area and the head of the flood discharge in the downstream area can be predicted. Finally, from the estimated probability of overflow, and the statistical values of the submerged area and the head of the flood discharge, the risk to the downstream area of the earth-fill dams can be evaluated.

AB - Decrepit earth-fill dams ought to be improved in order to mitigate natural disasters. Since there is a recent demand for low-cost improvements, the development of a design method for optimum improvement work at a low cost is the final objective of this research. As a basic step, the risk to earth fills during heavy rains is evaluated here. The rainfall intensity and the variability of the numerous soil parameters of the earth-fills related to soil erosion are dealt with as probabilistic parameters. When the maximum overflow head on a spillway bed becomes greater than the design overflow head, overflow occurs. The peak overflow head, hp, is determined within 72 hours of the rainfall, and the various rainfall patterns are tested by the Monte Carlo method. Furthermore, the statistical values of the parameters for the soil erosion are assumed in this research, and the variability of the discharge hydrographs are derived from the values. The discharge hydrographs are applied for the flood simulation as input waves. The submerged area and the head of the flood discharge in the downstream area can be predicted. Finally, from the estimated probability of overflow, and the statistical values of the submerged area and the head of the flood discharge, the risk to the downstream area of the earth-fill dams can be evaluated.

KW - Earth-fill dam

KW - Flood simulation

KW - Overflow

KW - Rainfall model

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M3 - Conference contribution

AN - SCOPUS:84907071513

SN - 9787114105821

T3 - 5th China-Japan Geotechnical Symposium

SP - 298

EP - 303

BT - 5th China-Japan Geotechnical Symposium

PB - People's Communications Press

T2 - 5th China-Japan Geotechnical Symposium: New Advances in Geotechnical Engineering

Y2 - 18 May 2013 through 19 May 2013

ER -