The undisturbed soil at a given borrow pit is found to have the following properties: w = 15%; γ= 5 19.1 kN/m^3 ; Gs = 2.70. The soil from this borrow is to be used to construct a rolled fill having a finished volume of 38,500 m3 . The soil is excavated by means of a shovel and dumped onto trucks having a capacity of 4.80 m^3 each. When loaded to capacity, these trucks are found to contain, on the average, a net weight of soil and water equal to 72.7 kN. In the construction process, the trucks dump their load on the fill and the material is spread and broken up, after which a sprinkler adds water until the moisture content is equal to 18%. The soil and water are thoroughly mixed by a disc (or similar equipment) and then compacted until the dry unit weight is equal to 17.3 kN/m^3.
a. Assuming that each load is a full capacity load, how many truckloads are required to construct the fill?
b. What should be the volume of the pit that remains in the borrow area, after all the material required for the fill has been removed?
c. How many liters of water will have to be added per truck load, assuming that the moisture lost by evaporation during excavation, haulage, and handling is negligible?
d. If the fill should become saturated at some time subsequent to the construction and does not change volume appreciably, what will be its water content at saturation?