The natural material in a borrow pit has a mass unit weight of 110.0 pcf and a water content of 6%, and the specific gravity of the soil solids is 2.63. The specifications require that the soil be compacted to a dry unit weight of 122 lb. per cf and the water content be held to 5.5%. A. How many cubic yards of borrow are required to construct an embankment having a net section volume of 245,000 cy?
B. How many gallons of water must be added per cubic yard of borrow material assuming no loss by evaporation?

A. 288,030.91 cy

B. The amount of water that must be removed from the natural material is 483541.04254 gallons of water

Explanation:

The natural material in the barrow properties are;

The mass unit weight, γ = 110.0 pcf

The water content, w = 6%

The specific gravity of the soil solids, = 2.63

The desired dry unit weight, = 122 pcf

The water content, w₁ = 5.5 %

The net section volume, = 245,000 cy = 6,615,000 ft³

A.   = /

∴ = × = 6,615,000 ft³ × 122 lb/ft³ = 807030000 lbs

w = (/) ×  100

∴ = (w/100) × = (6/100) × 807030000 lbs = 48421800 lbs

The weight of solids

W = + = 807030000 lbs + 48421800 lbs = 855451800 lbs

V = W/γ = 855451800 lbs/(110.0 lb/ft.³) = 7776834.54545 ft.³ = 288,030.91 cy

V = 288,030.91 cy

The amount of cubic yards of borrow required = 288,030.91 cy

B. The volume of water in the required soil is found as follows;

= (w₁/100) × = (5.5/100) × 807030000 lbs = 44386650 lbs

The amount of water that must be added =   - = 44386650 lbs - 48421800 lbs = -4,035,150 lbs

Therefore, 4,035,150 lbs of water must be removed

The density of water, ρ = 8.345 lbs/gal

Therefore, V = 4,035,150 lbs/(8.345 lbs/gal) = 483541.04254 gal  of water must be removed from the natural material

b. check your rearview mirror

explanation: