12. (Horton's equation for infiltration rate, ). One can use Horton's equation to estimate the infiltration rate of water into soil if the rainfall rate exceeds the infiltration rate. The Horton's equation states that: f = fe+ (fo-fc) x e-kt where f is the infiltration rate (cm h:¹), fc is the equilibrium infiltration rate (cm h ¹), fo is the initial infiltration rate (cm h:¹), k is an empirical constant (h:¹), and t is time (h). Horton's equation can be integrated to yield an equation that represents the total volume of water that would infiltrate over a given period: (ſo − ƒc) × e-*¹] ×x dt = A₂ × [fet + fo=fe (1 − e-*¹)] V = A., [ ƒ x dt = A, U. + Ufo - [ 1₁ + As where As is the unit area (1 m²) and V is the volume (m³). Sothan loamy sand has the following characteristics: fc = 6.68 cm h:¹, fo = 8.81 cm h¹, k = 1.40 h ¹. Assuming the rate of precipitation exceeds the rate of infiltration throughout the storm event. 12.1. Find the infiltration rate at times of 12, 30, 60, and 120 min. 12.2. Compute the total volume of infiltration over 120 min in an area of 1 m²

12. (Horton's equation for infiltration rate, ). One can use Horton's equation to estimate the infiltration rate of water into soil if the rainfall rate exceeds the infiltration rate. The Horton's equation states that: f = fe+ (fo-fc) x e-kt where f is the infiltration rate (cm h:¹), fc is the equilibrium infiltration rate (cm h ¹), fo is the initial infiltration rate (cm h:¹), k is an empirical constant (h:¹), and t is time (h). Horton's equation can be integrated to yield an equation that represents the total volume of water that would infiltrate over a given period: (ſo − ƒc) × e-¹] ×x dt = A₂ × [fet + fo=fe (1 − e-¹)] V = A., [ ƒ x dt = A, U. + Ufo - [ 1₁ + As where As is the unit area (1 m²) and V is the volume (m³). Sothan loamy sand has the following characteristics: fc = 6.68 cm h:¹, fo = 8.81 cm h¹, k = 1.40 h ¹. Assuming the rate of precipitation exceeds the rate of infiltration throughout the storm event. 12.1. Find the infiltration rate at times of 12, 30, 60, and 120 min. 12.2. Compute the total volume of infiltration over 120 min in an area of 1 m²

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter6: Hydraulic Conductivity

Section: Chapter Questions

Problem 6.8P

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