When planning a demolition project, it is important to understand the unique needs of the project, including whether or not asset recovery, concrete crushing and recycling, scrap metal demolition, and more will be necessary.
When working with a commercial demolition contractor, they may note these conditions and recommend a course of action based on them. This article is meant to offer general information about concrete demolition and recycling, as actual processes can vary based on local ordinances.
When Do You Need to Demolish and Recycle Concrete?
Concrete structures need regular maintenance just like any other building material. Patching and resurfacing can help extend the life of a concrete structure, but there may come a time in which the concrete will need to be replaced.
Here are some common signs that indicate concrete should be demolished and recycled:
- Sunken slabs: Concrete slabs can sink when the subgrade, the native or compacted soil beneath the slab, wasn’t prepared correctly. Loose dirt allows for water to seep in and undermine the concrete slab. Alternatively, the subgrade may have been properly compacted, but the slab is bearing too much weight, causing it to sink.
- Deep cracks: When a concrete structure has long, deep or widespread cracks in places where settlement has occurred, you know it’s time to replace the concrete. This can be due to erosion, heavy loads, or improper subgrade.
- Frost heave damage: Frost heave occurs when the soil, or other surface the concrete structure may be on, expands due to frozen groundwater. This is a common occurrence in cold climates.
- Damaged concrete surfaces: When the surface of the concrete structure displays spalling or pitting, it becomes more economical to replace the concrete rather than trying to repair the surface.
- Additions to construction: A structure that has been modified or retrofitted will often need to have older concrete elements removed if they interfere with the improvements.
- New construction: Sometimes a complete demolition is called for when a new building with a different purpose or design is being built in its stead. Old curbing is often removed to make way for new street improvements.
- Faulty concrete: If a batch of concrete has an issue that affects its quality, it must be removed fully and repoured in order to ensure structural integrity.
4 Methods Used to Demolish Concrete Structures
There are a variety of demolition methods, but when it comes to concrete crushing and recycling, the four listed below are the most common.
1) Pressure Bursting
When a situation calls for a dust-free, controlled, and quiet concrete removal, pressure bursting is the best option. There are two kinds: mechanical and chemical. Holes are drilled into the concrete and then a lateral force is applied. Mechanical pressure bursting uses a hydraulic pressure machine, while chemical pressure nursing uses an expansive slurry. Then, the concrete is removed by hand or crane.
2) Pneumatic or Hydraulic Breakers
Used primarily on demolitions of foundations, pavements or bridge decks, breakers are mounted on machines and essentially pound away at concrete, breaking it down with a steel reinforced hammer. These machines can be controlled remotely, performing hundreds of blows per minute.
3) Ball and Crane
This is one of the oldest and most common methods of concrete demolition, which allows workers to break down the structure into smaller pieces that can then be sorted and recycled or discarded. While concrete can be easily broken down with this method, disassembling concrete with steel reinforcement can be difficult. It also produces lots of dust, noise and vibration.
When portions of a building are being removed, dismantling the slab with tools like saws, thermal lances, or high-speed water jets can allow the concrete slab to be precisely removed. A crane typically will then remove the slab. This method allows for the complete demolition of a structure with minimal noise and dust or impact on surroundings.
The Best Demolition Company in Oregon
At Elder Demolition, we use concrete recycling to help offset the costs of demolition, both financial and environmental. Our expert crews are trained in the careful dismantling and recovery of structures of all shapes and sizes before preparing the materials for recycling.
We offer a wide range of commercial and industrial demolition services and scrap metal recovery in Oregon, Washington, Idaho, and Montana. Through asset recovery, our expert demolition contractors help divert waste from landfills and turn it into a valuable opportunity that maximizes your bottom line. Contact us today to learn how we can help you.