Concrete Basics
Many of the buildings in ancient Rome, Italy were constructed with concrete. The Pantheon is one of them, it was built in 447 BC and is more than 43 meters high. It is constructed of both marble and concrete. New York City would be spread out about a hundred miles in each direction if it weren’t for concrete. What is so amazing, is that it is a simple mixture of cement, sand, gravel, and water. Concrete is an awesome construction material!
Modern day foundations
Modern day home foundations (in the northern regions; basements) are made of concrete. Wooden forms are built to size along with steel reinforcement and then a wet concrete mix is poured in. It will set up in about 7 hours, depending on the temperature; during the hot summer days. Water is lightly sprayed to keep it cool and not cure too rapidly. It is fully cured in 30 days thereby achieving its maximum strength.
Unlike duct tape, concrete isn’t an absolute miracle material and before you can understand what can go wrong with a foundation, you need a quick lesson in the world of concrete. It can withstand the weight of your house because it has great compression strength, but it’s lacking in tensile strength, which is the ability to withstand longitudinal stress. Think of taking an unsharpened pencil, standing it upright, and trying to break it by pushing down on it (compression). That’s a lot tougher than trying to break it by snapping it in half with your hands (longitudinal stress). To make up for this lack
of tensile strength, rebar (or steel reinforcing bars) is added to concrete foundations.
The Romans also used concrete for constructing over 5,000 miles of roads with a primitive mix of mortar, gravel, coarse sand, hot lime, water, and even animal blood from time to time. Don’t think for a minute that just because it was a primitive mix that is was inferior to modern day concrete; The Pantheon cathedral ceiling was made of concrete and it is a marvel in that it is crack-free.
Category: New Construction, Uncategorized
