Science Buddies: "Ask an Expert"

So i decided to do a project on testing cement with different additives. What im doing is im taking two different mixs from different companies and im adding one additive per sample for a total of 10 small blocks then im testing for durability, strength and weaknesses. What i have to do is write a research paper on it but im not sure on where to start. Any help is appreciated. Thanks!

From my other post of my project, im putting a peice of wood in the top to see how much force is necessary to break it away from the cement. Wondering if that is a good idea? Also what can i use that is readily available to test the force. Thanks!

Hi-I'm not sure what your experiment is-maybe the moderator can combine them into one post?

Also, do you mean cement or concrete? Cement is only one component of concrete. Maybe with a little more info I can be of help.

Hi th3xf4ctor,
I combined your topics into one topic in the Physical Science forum. Please keep future posts in this topic using the "post reply" button. Thanks!
Have you read this project guide?
https://www.sciencebuddies.org/science- ... p010.shtml
You could use that procedure as a starting point, and then add some complexity to bring the project up to your grade level. Hopefully the other experts will have additional suggestions.
Good luck!
Chris

im putting a peice of wood in the top to see how much force is necessary to break it away from the cement. Wondering if that is a good idea?

Wood and cement/concrete have poor adhesion. For this reason, wood is often chosen as the form material in which to pour concrete. I personally don't know of any material that will adhere to wet cement or concrete. Construction adhesives work well, but only after the cement has dried and partially cured.

Also what can i use that is readily available to test the force.

There are different kinds of "strength" (tensile, tension, compression, torsion). The methods for testing these different strength properties requires different techniques. Weights are good for some measurements (say hang a large bucket from the object and add water or sand to the bucket until the object breaks then weigh the bucket. Spring scales can be used to measure forces; however, finding one with the correct range maybe difficult. Torque wrenches can be used to measure torsion. Cement and concrete have very high compression strength so measuring it will be difficult with without some hydrolyic cyliders and pressure gauges and bearing plates and ....

One of the standard tests for concrete is the unconfined compression test (look it up). If you are testing mortar (sand-cement), you can get by with small samples. Half-inch diameter by half inch high would not be too small, because the grain size of the sand is much smaller. Using the principle of the lever (2 X4?) and using weights (even a container to which water is added) one could build a simple compression testing apparatus.