Just as there are several ways to skin a cat, there are several ways to demolish a building.
There are multiple factors to think about before starting demolition, including disposal methods, location and building material. Continue reading to learn the most common demolition procedures and the situations which are best to use them.
Crane and Ball
In this type of demolition, a wrecking ball that can weigh more than 13,000 pounds is swung repeatedly or dropped onto the building. It’s crucial that the crane operator knows what he is doing because failure to swing the ball smoothly can overload the crane.
The Crane and Ball method is usually used for masonry and concrete structures. However, this technique is not suitable if the building is very large or contains rebar. It’s also ineffective if there are noise, vibrations or dust limitations.
To implode a building, construction crews put in enough explosives to rid the structure of its vertical structural supports. The timing and placement of the explosives are crucial, so that each floor in the building falls into itself, which leaves crews with just a pile of rubble to clean up.
Implosions are typically used in urban areas on large structures. Ideally, crews can direct an implosion to tip buildings in specific directions where there are no pre-existing structures. Unfortunately, this is not always the case.
When implosions are performed in a compact urban area, construction companies have to make sure that the building being demolished collapses straight down – a task so tricky few companies even attempt it.
High Reach Arm
A high reach (over twenty meters) demolition requires a base machine such as a tank, excavator, counterweights or engine.
The demolition itself is performed by a telescopic arm equipped with a primary tool such as crushers, hammers or shears, or by a three-section demolition arm. Factors such as the shape and height of the structure and the site conditions need different considerations when operating the demolition arm.
This procedure can be used for masonry, mixed-material structures and reinforced concrete. Click here to see what a Caterpillar 385C high reach demolition of a multiple-story building looks like.
Selective demolition covers the removal of ceilings, walls, exterior building components and floors from a building. Jacks are typically used in multiple-story building demolition to hold up the remnants of the building until it can be dismantled entirely.
A CNN video shows a selective demolition of a 40-story hotel in Tokyo in an effective, quiet and clean manner.
Selective demolitions are primarily used to salvage and recycle the building materials. Clients and builders alike typically use this method, even though it is usually slower than others.
To read more about construction-related topics or building demolition, check out the H Brown Machine Shop blog.