Question

16. (6 pts) Porosity = pore volume/total volume of hydrated cement specimen. The capillary pore volume can be estimated based on the following equation: Ve=w/e-0.360 cm /g of original cement powder where Ve= capillary pore volume; and a = degree of hydration. The specific gravity of cement is 3.15. For a cement paste with w/c=0.5, a =0.75, and assuming the total (external) volume of cement paste does not change after mixing, calculate the following: 1) (3 pts) The capillary porosity (only consider capillary pore volume) *Assume 1 g of original cement powder 2) (3 pts) The total porosity (consider capillary pores + original entrained air) with original entrained air content of 4%. *Assume 1 g of original cement powder

Answer 1

Answer!- The Given information is Ve = W/ -0.364 cm3/g Specific gnavity of cementa 3-15 Wh=0.5 a=0.75 u v Ve=0.5-0.36 (0.75) = 0.23 cm3 Volume is Same after mixing total Volume of 1cm3 of cement Assuming تل ponosity (no) Pore volume Total volume 0.23 0.23 2) air content = 4y = 0.04 V -0.04 V Ve Va + V porosity = =) -0.040, + 04 Vy louco-23) n = 0.2392