FREQUENTLY ASKED QUESTIONS ON PAVEMENT BREAKING


QUESTION: We have a road that is 6-inch thick concrete with 4 or 5-inches of asphalt topping. Do we have to mill the asphalt off, before you can break the concrete?

ANSWER: Quite often the Impactor 2000 will break both the asphalt and the concrete at the same time. It is dependent on how old the asphalt is and how small of debris you want to produce. If the asphalt is old and brittle, both layers may break very well. If the asphalt is not brittle, because it still contains allot oil, it may absorb the impacts and protect the underlying concrete. Only minor breaking of the concrete below may occur in this case. It is often possible to loosen the asphalt with the Impactor 2000, enough that it may be bladed to the side or scooped up with a loader. Once it is out of the way, the Impactor 2000 can effectively break the concrete. Another factor determining how well asphalt will break is the temperature of the asphalt. The warmer the asphalt is, the harder it will be to break.


QUESTION: We have 8-inches of asphalt placed on grade, no concrete under it. Will the Impactor 2000 break it?

ANSWER: Quite often the Impactor 2000 will do a good job in this case, but keep in mind, many of the factors in the previous question apply here also. Another factor that applies in this case is the firmness of the base and sub-base. If the firmness is not adequate, it will allow the asphalt to deflect into it. This may determine the smallest size of debris produced. With all factors in your favor, the asphalt may be reduced to an average size of 8 to 16-inches. With less than favorable conditions you may get around 24 to 36-inch pieces.


QUESTION: Our concrete is 10 inches thick and has #4 reinforcing @ 6-inches on center longitudinally. Will the Impactor 2000 break this so we can load it out? We’re disposing of both the concrete and rebar.

ANSWER: Usually concrete like this needs to be broken down to 12-inch or smaller, to debond enough of the reinforcing, so loaders can get it into trucks. Don’t spend more time than you need. Just relieve it enough the loaders can handle it. After all, your disposing of it. On an average, 2,350 sq. yds. of this can be broken in an hour.


QUESTION: What effects how well or easily the concrete is going to break?

ANSWER: The support given by the base and sub-base, pavement strength (mix), condition, aggregate, and ground water.


QUESTION: How small can we break concrete down with an Impactor 2000?

ANSWER: If concrete is 10-inches thick, breaking it down to an average of 10-inch size pieces it not difficult, especially if the factors in question 4 are in your favor. To break concrete into pieces smaller than its thickness (Rubblization), the condition of the base and sub-base become very important. The density of the base and sub-base will definitely set the limit. Imagine putting a walnut on hard dirt and hitting it with a hammer. Then put one on soft wet soil and hit it. I assure you the first walnut is going to be in smaller pieces.


QUESTION: Can the Impactor 2000 rubblize concrete full depth to a uniform size?

ANSWER: Nothing that we know of can. If you need material that uniform, it should be broken with the Impactor 2000, taken to a crusher for further reduction, and screened. All methods for rubblizing concrete attack the concrete from the top. Pieces toward the bottom will be somewhat larger.


QUESTION: Does reinforcing make the concrete harder to rubblize?

ANSWER: No. Pavement reinforced with bar type reinforcing (not mesh) is actually easier to rubblize. The reinforcing steel helps to hold the concrete in place so it can be broken. This helps when your base and sub-base are less than firm.


QUESTION: Can we debond the reinforcing in 10 inch thick concrete with an Impactor 2000, and recover it?

ANSWER: Yes. Recovery of reinforcing can be as high as 100% if the factors mentioned in Question 4 are in your favor. If they aren't you might be looking at a slightly lower percent of recovery.


QUESTION: Can the Impactor 2000 be used to remove concrete on a bridge deck?

ANSWER: We highly recommend against using the Impactor 2000 on bridges or any elevated platform. The impacts could cause structural damage resulting in a failure of the bridge or platform, and possible injury or death to the operator or others.


QUESTION: Can the Impactor 2000 be used to remove on-grade building floor slab?

ANSWER: Yes, and the same rules apply here that apply to roads. Actually the Impactor 2000 can be used on any flat work on-grade. It is best if there are no drop-offs at the pavement edge. This will allow the operator to smoothly drive on and off of the slab, making his turn-arounds off the slab if he desires.


QUESTION: How close to a wall or barricades can we break with the Impactor 2000?

ANSWER: The Impactor 2000’s drum can be operated as close as 24 to 30-inches from a wall or barricade. Some cracking will radiate as far as the wall or barricade, and sometimes further. However, the effect will not be as intense as that occurring under the drum and therefore will not produce the same results.


QUESTION: Can we use a rubber tired loader to pull the Impactor 2000?

ANSWER: We don’t recommend it, but it is possible. What we recommend are agricultural type tractors in the 175 to 200 hp range. To operate an Impactor 2000, it helps if you can make visual contact with it to assure drum positioning. With an ag-tractor this visibility is unobstructed, while with a loader the engine is in the way. The turn around radius with many ag-tractors is much shorter than with a loader. When trying to turn around on a road this is important. Ag-tractors have the necessary hydraulics for operation of the Impactor 2000’s systems, while loaders don’t. Ag-tractor are more economical to operate and better serve the operator's comfort.


QUESTION: If we use the Impactor 2000 for pavement breaking, what maintenance must we perform to keep it in good operating condition? What about wear on the drum?

ANSWER: The number one thing is to grease your machine on a regular basis before using. The operator's manual shows all the locations and recommends the frequency. There are only 2 roller bearings on the Impactor 2000 (not counting the wheel bearings). These 2 bearing, are the bearings the drum rotates on. They are in an enclosed area, well protected, and if you give them a squirt off grease every day before operating, they'll last for years. Actually, we know of none that have ever been replaced. All other bearings are self aligning type bearings and should last for years too, if you keep them greased. By the way, all the bearings used on the Impactor 2000 are common, and can be purchased in any major city throughout the world.

The drum rolls on concrete, so yes, there is wear. There are 3 breaking bars on each of the 4 sides of the drum. These bars are what deliver the impact to the pavement. Usually you can break about 8 to 10-miles of 2-lane highway down to 16-inch pieces, before you need to attend to the hard-facing on these bars. A good welder may spend about 4 hours rebuilding the hard-facing. Each of the 4 drum lifting lobes (the small rounded corners of the drum) have 3 wear plates. Your welder might spend about 2 hours of touch-up on these plates after he does the bars. That's it. About 6 hours total, but look at all the concrete you broke.

Do you have a question? Ask us...


HOME | IMPACTOR 2000 | IMPACTOR 3000 | SPECIFICATIONS | PAVEMENT BREAKING | SOIL COMPACTION | QUESTIONS & ANSWERS | CONTACT US
Impact Roller Tech Main Page Impactor 2000 Impactor 3000 Specifications for Impactors Pavement Breaking Soil compaction Frequently Asked Questions For More Information, Contact Us Please