OUESTION $5(25$MARKS$)$

a$)$ Give the soil classification systems and the basis of their classification. $5$marks

b$)$ The results below are from tests carried out on a soil sample. Classify the soil sample using ALL systems stated above and compare the results from the various systems. State with reason whether the soil can be used in its natural state as a subbase material. If not make the necessary recommendations for the soil to be used$\mathrm{.}10$marks

$\backslash$table$[[$Sieve no$.,$Percent passing$],[4,98],[10,93],[40,75,],[100,73,],[200,62,]]$

c$)$ Describe any quality control test used to ascertain any of the properties for each of the following materials,

i$.$ bitumen and

ii$.$ aggregates used on roads.