How to Crush Concrete in Industrial Demolition

One of the greatest assets on a demolition site is also one that may seem simple to ignore—concrete. After concrete serves its purpose, it has the potential to offset the costs of a project when reused or sold for recycling. Rather than send concrete from old buildings to landfills, forward-thinking Oregon demolition contractors crush it in to useful gravel or into an aggregate that you can use to make new concrete. As construction materials are increasingly evaluated by their ecological characteristics, recycled concrete continues to gain importance in the industry.

Uses for Crushed Concrete

• Foundations
• Landscaping
• Leveling
• Structural fill
• Road bases
• Make new concrete
• Erosion control
• Backfill materials

Advantages of Crushed Concrete

• Eco-friendliness: Using crushed concrete to produce new aggregate preserves virgin supplies and uses less energy than mining virgin aggregate. Its use also reduces a project’s carbon footprint, whether you use it in gravel form or to make new aggregate.
• LEED points: Using recycled concrete will qualify a project for LEED-related recycled material credits. When you reuse the material onsite or obtain it from a local source, the project may earn LEED-related local credits.
• Construction benefits when made into new concrete: Crushed concrete aggregate has a faster initial set time than virgin material, is lighter in weight, and simpler to place and strike off. When it has the right proportions, it has the same shrinkage properties as other concrete. Because recycle concrete is “creamier” or “fattier,” it is simpler to finish.
• Return on investment: With virgin aggregate sources becoming more depleted, the demand for crushed concrete continues to grow as building trends continue on an upward curve.

Concrete Crushing Steps in Oregon Demolition

1. Remove the concrete from the respective building: Oregon demolition companies that recycle concrete use specialized equipment to tear down a building, including high-reach excavators with hammer, breaker and shear attachments.
2. Remove extraneous materials: Concrete must be free of materials, such as glass, wood, plastic and metal. The best contractors use strong electromagnets to remove rebar and other types of scrap metal that a client can sell.
3. Crush the concrete: The contractor brings in concrete crushers to process and recycle the materials on-site. Workers use an excavator to load the concrete into the crusher. The machinery’s interlocking teeth break the concrete into smaller pieces. If an Oregon demolition company does not own concrete crushers, it might ship the materials to a recycling plant.
4. Separate the concrete: Workers separate the crushed concrete by size. They then place the larger pieces into the crusher again to make them smaller.
5. Scrap metal removal: Smaller pieces of scrap metal often go through the concrete crusher. After processing the concrete, workers use electromagnets to remove the metal objects.

Types of Concrete Crushers

Jaw Crushers

Jaw crushers are similar to nutcrackers as they break down concrete between two vertically oriented jaws that a weighted flywheel powers. In general, one of the jaws remains in a fixed position and the other—the swing jaw—moves back and forth. As the equipment crushes the concrete using compressive force, the smaller pieces pass through a crushing chamber while the larger pieces remain in the jaws. Blake crushers have a swing jaw in the upper position, and can have single- or double-toggle jaw crushers. Conversely, dodge crushers have swing jaws fixed at the lower positions, forming a tapered chute. Universal crushers situate the swing jaw at an intermediate position.

Jaw crushers are versatile and economical. They are good for processing hard and abrasive materials. They also tend to have lower maintenance costs.

Impact Crushers

Rather than use compressive force to crush concrete, impact crushers use impacts to crush materials. Hammer mill crushers, or horizontal shaft impactor crushers, break concrete by hitting it with a strong hammer that’s fixed on a spinning rotor’s outer edge. This type of crusher is better for softer, nonabrasive materials.

Vertical shaft impactor crushers have high-speed rotors with tips and a crushing chamber that slings pieces of concrete against a hard surface—usually an anvil—to break it into smaller pieces. This type of equipment relies on velocity to crush the concrete, rather than surface force. As a result, the breaking force is applied evenly across the concrete’s surface and throughout its mass. This force causes the concrete to break along the fissures within it. The velocity at which the machinery throws the concrete against the anvil and the distance between the anvil and the end of the rotor dictate the size of the crushed concrete. Vertical shaft impactor crushers are more capable of handling more abrasive materials than its horizontal shaft counterpart.

Impact crushers have high reduction ratios and capacities. They are good at separating rebar and wire mesh from concrete. The parts are also simple to replace.

Cone Crushers

Many demolition contractors do not use cone crushers as often as impact or jaw crushers. As the name implies, a cone crusher has a canonical shape. It breaks concrete by squeezing it through an eccentrically gyrating spindle and a concave hopper. When the concrete enters the crusher, it is squeezed between the spindle’s mantle and the hopper’s liner. When the larger pieces become smaller, they fall into a lower position, where the crusher processes them into even smaller pieces. When the pieces are small enough, they fall through an opening at the bottom of the crusher.

Cone crushers have a sturdy construction, lower operating costs, and are simple to adjust. They also offer high productivity rates as they can process wet material.

Elder Demolition specializes in an asset recovery. As one of the largest concrete processors on the West Coast, we maintain a fleet of crushers that are ready to serve your recycling needs. Get in touch with one of our Oregon demolition specialists today to learn more about how recycling concrete will offset your project’s costs and reduce its environmental impact.