For this project, which tests the strength of sand vs. gravel, mix three batches of concrete according to the package instructions. Mix one batch with sand and another batch with gravel and use only concrete in the third batch. Pour them into three separate molds and allow them to dry for a few days. You can test the strength with a pressure gauge and a hydraulic press or take them to a twining lab, where engineers can test them accurately with gauges.
Does more or less water affect the strength of concrete? For this project, mix several batches of concrete with different portions of water. Pour each batch in a separate mold and mark them according to the proportion of water used. Allow them to dry for several days. Test the strength of the batches yourself or take them to a twining lab for engineers to test. Use a hydraulic press and a pressure gauge to test the strength of the batches yourself.
Which formula melts ice more efficiently on concrete? Mix four batches of concrete according to the package directions. Pour into separate forms and allow to dry for a few days. Cover each block of concrete with water and freeze to 30 degrees Fahrenheit. Treat one frozen block of concrete with sodium chloride (rock salt), one with calcium chloride, one with potassium chloride and one with magnesium chloride. Make notes on which works the best. Continue to wet, refreeze and treat the concrete blocks at progressively lower temperatures. Determine which deicers work most effectively at what temperatures.
Does liquid affect the strength of a concrete mix? For this project, mix one batch of concrete according to the package directions. Mix several other batches of concrete using different liquids. Use the liquids in the same proportion that is recommended for mixing with water. Try milk, orange juice and bleach. Do not mix more than one liquid in each batch. Pour each batch into a separate mold and mark it with the liquid used in that batch. Allow to dry for several days and test them for strength.
What type of concrete is the most reflective? Mix one batch of white concrete and another of regular cement. Cement is normally a light gray color. Pour them into molds and allow them to dry for a few days. Use lights to test the reflectivity of the two colors of cement. Take them into a dark room and test the reflectivity again. How can reflective cement be used to make parking lots, curbs, driveways and sidewalks safer in cities? How can reflective concrete be used to conserve energy?