What does it take to demolish a building?

The first step to successfully demolish a building is to remove any debris within the structure. Next, destruction crews begin to knock down any non-load bearing walls. This allows for a cleaner break at each floor: if these walls were left in tact, it would stiffen the building, negatively effecting the collapse. They may also weaken supporting columns with sledgehammers or steel-cutters. Sounds fun so far. Next, blasters (explosives experts) start loading the buildings columns with explosives. Different explosives are used for different materials, and more or less of an explosive is used depending on the thickness of the material. The two materials typically dealt with are steel and concrete. Concrete is loaded with traditional dynamite or similar explosives. The dynamite does its job by completely disentigrating the concrete. Steel is a bit more complicated, because of its high density. It is loaded with cyclotrimethylenetrinitramine, RDX for short. Instead of disentegrating the column, it actually slices right through the steel, cutting it completely in half.To ignite both RDX and dynamite, you must apply a severe shock. In building demolition, blasters accomplish this with a blasting cap, a small amount of explosive material (called the primer charge) connected to some sort of fuse. To control the sequence, blasters typically configure the blast caps with some sort of delay mechanism. Blasters determine how much explosive material to use based largely on their own experience and the information provided by the architects and engineers who originally built the building. But most of the time, they won't rely on this data alone. To make sure they don't overload or under-load the support structure, the blasters perform a test blast on a few of the columns, which they wrap in a shield for safety. After they conclude what the proper explosive amount is, they wrap the columns in a shield to avoid flying debris from damaging near-by structures. Its almost that time.