Ex 12.1: the maximum allowable soil salinity at root zone 9 mmhos/cm, find the leaching requirements (depth) and depth of irrigation water if; • Seasonal consumptive use 150 cm • Electrical conductivity of irrigation water 1.5 mmhos/cm • Leaching efficiency 60% (percentage of effective leaching water depth to total required leaching depth)

Ex 12.1: the maximum allowable soil salinity at root zone 9 mmhos/cm, find the leaching requirements (depth) and depth of irrigation water if; • Seasonal consumptive use 150 cm • Electrical conductivity of irrigation water 1.5 mmhos/cm • Leaching efficiency 60% (percentage of effective leaching water depth to total required leaching depth)

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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Determine the leaching requirement when the electrical conductivity of drainage water from soil was found as 20 m-mho/cm at 20% reduction in yield of the crop. Take Ei= 1.5 m mho/cm What will be the required depth of water to be applied if the consumptive use is 55.5 mm.
Measurement of a 25 ºC groundwater sample isolated from the atmosphere indicates that pH = 6.35 and total ALK of 1 meq/L. b) What will the new alkalinity be if 0.5 mM hydrated lime (formula Ca(OH)2) is added to the source water?
1. DLSU D is to install rapid sand filters downstream of the settling tank. The design loading rate is selected to be four times the surface per filter which is limited to 45 m?. The design capacity of the waterworks is 0.30 m³/s. Design the number and size of filters and calculate normal filtration. 2. A sieve analysis curve of a typical filter sand gives dgo= 0.99mm and UC = 1.38. What are its d10 and deo? 3. Troughs are 30ft long and width is 20% less than it length and one fourth of length is the measure to the center with horizontal flat bottom. The backwash rate is 24 in/min. Estimate (1) water depth of the troughs with free flow into the gullet, and (2) the distance between the top of the troughs and the 30-in sand bed. Assuming 40% expansion and 6in in free board in the troughs and 8 in of thickness. 4. Estimate particle size of ilmenite (sg 2x sand =5.4) and anthracite (s.g. 2/3 of sand = 1.8) which have settling velocity of silica sand 0.80 mm in diameter (s.g. 2.7).
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