Question

Several students were interested in using tempered glass as an additive for a portion of the fine aggregate in a Concrete Mix Design. They stated tempered glass has a high compressive strength and is an available resource. Their Control mix was to be 5 pounds of Coarse Aggregate, 5 pounds of Fine Aggregate, 2.5 pounds of cement, and 1.2 pounds of water. Their research idea was to use 5 pounds of Coarse Aggregate, 2.5 pounds of Fine Aggregate, 2.5 pounds of Textured Glass, 2.5 pounds of cement, and 1.2 pounds of water. After the curing process and the compression tests the control mix was 84,000 pounds or 6700 psi; the proposed new mix was 69,500 pounds or 5500 psi. Does the new idea show promise (Yes or No)? Where does one go from here? Explain your answer?

Answer 1

Answer)

The following are the observations that can be made from the results obtained from the research tests.

(1) Their control mix had a 5 pounds of coarse aggregate, 5 pounds of fine aggregate, 2.5 pounds of cement and 1.2 pounds of water and new mix had 2.5 pounds of textured glass instead of 2.5 pounds of fine aggregate of the total of 5 pounds of fine aggregate. Textured glass was available in that area.

(2) But the results have proved that the compressive strength of new mix was 5500 psi which is lesser than the compressive strenth of control mix which had a compressive strength of 6700 psi.Hence with respect to compressive strength the new mix was not a big success.

(3) Reduction in compressive strength of new mix is only 15 to 20 percent when compared to the control mix.But the textured glass is readily available in that place making it cheaper and economical than the regular fine aggregate so this new mix could be used in economical construction where the compressive strength required is comparably lesser than the control mix and is in the range of the compressive strength of new mix.

(4) So with respect to economical construction where the strength requirement is comparably lesser this new mix was a success.

(5) This experiment can be continued and the proportions of fine aggregate and textured glass can be varied to obtain an equilibrium in economy and strength aspects.

(6) But if the strength requirements are in the range of control mix this new design will not meet the requirements and hence it can be stopped.