Question

In a Marshall method of mix design,the coarse aggregate, fine aggregate,filler and bitumen having specific gravities of 2.62, 2.72, 2.70 and 1.02 respectively, are mixed in the ratio of 55, 34.6, 4.8 and 5.6 percent respectively. The theoretical specific gravity of the mix would be

• A. 4.88
• B. 1.63
• C. 3.26
• D. 2.44

Answer 1

The correct option is D 2.44

Theoretical specific gravity,

$G_s=\frac{W_1+W_2+W_3+W_4}{(\frac{W_1}{G_1}+\frac{W_2}{G_2}+\frac{W_3}{G_3}+\frac{W_4}{G_4}+)}$

$=\frac{55+34.6+4.8+5.6}{(\frac{55}{2.62}+\frac{34.6}{2.72}+\frac{4.8}{2.70}+\frac{5.6}{1.02})}=2.44$