On Oct 16 Monday’s lab, we tested three cylinders of the 14-day concrete for compressive strength, modulus of elasticity, and Poission’s ratio. then

On Oct 23 Monday’s lab, we tested another three concrete cylinders for 21-day compressive strength. Please take look of the fractured specimens pics attached and identify what kind of fracture, and also compare the 14-day strength with the 21 days to see what happen. We made 8 specimens and did the test on 3 for after 14 days and 3 after 21 days. we left saved the remaining two specimens at the lab.

For the testing results of this group report please: (1) demonstrate the specimen variation of three specimens by calculating coefficient of variation (both 14-day and 21-day); (2) demonstrate and discuss the effect of curing days on the compressive strength; (3) calculate the modulus of elasticity and Poisson’s ratio using the data and lab handout I post under Resources; and (4) discuss the fracture of concrete cylinders according to ASTM C39.