Effect of liquids on strength of cement

How Do Different Liquids Other Than Water Affect the Strength of Cement?

Objectives / Goals of the project

The project's goal was to see how different liquids other than water affect the strength of cement. The object of this project was to find out how to make stronger cement which might help buildings better survive earthquakes.

Methods and Materials used

The liquids used were water (the control), carbonated water, orange juice, ammonia, and bleach. Uniform cement blocks were made out of equal parts of dry cement and each liquid. Each block was tested for flexural strength and impact energy. Flexural strength is the ability of the block to withstand a heavy load. The block were tested with increasing loads until their failure. Impact energy measures the toughness of something; this was measured in foot-pounds. For each type of cement three measurements were taken by dropping a one-pound weight on a fragment starting at one-foot heights and then increased the height until the fragment fractured.

Results

By doing this experiment it was found that orange juice made cement weaker, while ammonia and bleach made cement stronger. To explain these surprising results the chemistry of cement was researched and pHs of all the liquids used, were tested. It found that the hydration of cement is an alkaline reaction and that the acidic liquid (orange juice) made the weakest cement while the basic liquids (ammonia and bleach) made the strongest cement. By adding basic liquids it must have made the chemical reaction of hydration stronger and faster thus making stronger cement.

Conclusions / Discussion

This experiment proves that basic liquids make cement stronger and acidic liquids make it weaker. In construction, concrete is used, which is cement mixed with gravel and metal which makes it stronger.

May be if basic liquids were used in cement, concrete would be even stronger which would make buildings and bridges more earthquake resistant. Perhaps construction sites should check the pH of their water before using it in their cement to make sure that it is not acidic which might affect its strength. Testing the strength of cement with liquids other than water shows that basic liquids make cement stronger while acidic liquids make it weaker.