Construction aggregates share of total U.S. raw material consumption, 1900–1998. 

Demolition by implosion of the Aladdin Hotel, Las Vegas, Nevada, April 27, 1998. Photo by

Ethan Miller, courtesy of The Las Vegas Sun newspaper.

80

70

60

50

40

30

20

10

0

190019061912191819241930193619421948195419601966

197219781984

19901996

PERCENT

YEAR

Recycled Aggregates—Profitable Resource Conservation

 

Aggregates are Required for Construction Projects

Aggregates are composed of rock fragments that may be used in 

their natural state or after mechanical processing such as crushing, 

washing, and sizing. Natural aggregates consist of both sand and 

gravel, and crushed stone. Recycled aggregates consist mainly of 

crushed concrete and crushed asphalt pavement.

Construction aggregates make up more than 80 percent of the total 

aggregates market, and are used mainly for road base, riprap, cement 

concrete, and asphalt. Aggregates provide bulk, strength, and wear 

resistance in these applications.

As American society evolved from rural-agrarian to urbanindustrial, the demand for supporting infrastructure grew. Construction 

aggregates increased from 36 percent of all raw materials used in the 

United States in 1900 to 70 percent in 1958, a compound annual 

growth rate of 1.15 percent. From 1958 to 1998, Americans have 

maintained their use of construction aggregates at 70–73 percent of 

their total raw material demand.

Recycled Aggregates Originate from Construction 

and Demolition Debris

Much of the infrastructure that has been constructed since the 

1950’s, particularly roads, has become, or is becoming obsolete and in 

need of replacement or repair. As Americans go about tearing up roads 

and tearing down buildings, they generate large quantities of 

demolition wastes, yielding over 200 million t (metric tons) of recycled 

aggregates annually.

Demolished infrastructure can be either disposed in landfills or 

recycled. The decision is usually made by the demolition contractor, 

taking into consideration regional economics, contract terms, and legal 

mandates. 

Asphalt Recycling

 Asphalt paving materials are recovered from demolished roads. 

These are valuable, both for the asphalt binder and for the aggregates. 

More than 100 million t of worn-out asphalt pavement are recovered 

annually. About 80 percent of the recovered material is currently 

recycled, and the remaining 20 percent reports to landfills. Two-thirds of 

the recycled material is used as aggregates for road base. The remaining 

one-third of recycled material is reused as aggregates for new asphalt hot 

mixes (Kelly, 1998).

Concrete Recycling

 Aging U.S. infrastructure, decreasing availability of landfill space, and 

environmental concerns work together to increase concrete recycling.

There are two approaches to recycling concrete. One alternative is to 

haul the concrete debris to a permanent recycling facility, usually close by 

to minimize transportation costs, for crushing and screening. The other 

approach is to do the crushing and screening at the demolition site where 

the aggregate is reused as soon as it is processed.

Recycling at the demolition site (see photo on back) reduces heavy 

materials hauling, thereby reducing transportation costs, energy use, and 

wear and tear on roads and equipment.

Recycling—Small Market Share, but Large Tonnage

An estimate prepared by William Turley, Construction Materials 

Recycling Association, Lisle, Illinois, states that about 100 million t of 

concrete is recycled annually into usable aggregates. Aggregates produced 

from recycled concrete supply roughly 5 percent of the total aggregates 

market (more than 2 billion t per year), the rest being supplied by 

aggregates from natural sources such as crushed stone, sand, and gravel. 

Preliminary data indicate that in 1998, 3,400 U.S. quarries produced about 

1.5 billion t of crushed stone, of which about 1.2 billion t was used in 

construction applications. About 5,300 sand and gravel operations 

produced more than 1.0 billion t of construction aggregates in 1998.

Concrete Recycling Product

The bulk of the aggregates recycled from concrete—an estimated 68 

percent—is used as road base. The remainder is used for new concrete 

mixes (6 percent), asphalt hot mixes (9 percent), high-value riprap (3 

percent), low-value products like general fill (7 percent), and other (7 

percent) (Deal, 1997, p. 11).

The low usage rate of recycled aggregates from concrete (15 percent) in 

high-value new concrete and asphalt hot mixes, compared to the higher 

U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet FS–181–99

February 2000 Printed on recycled paper
Portable, closed-circuit crushing and screening operation, designed specifically for on-site 

processing of concrete, courtesy of Cedarapids, Inc., Cedar Rapids, Iowa.

usage rates in lower valued products, is related to quality issues, both 

real and perceived. State agencies have been slow to accept recycled 

aggregates from concrete for high-quality uses such as road surfacing. 

Specifications, based on considerable research and favorable in-service 

experience, have allowed its use mostly as road base material.

Some States are experimenting with the conversion of existing 

worn-out concrete roads to rubble-in-place. The old concrete surface is 

broken up and compacted, and asphalt pavement is placed over the 

enhanced base, composed of the original base and the new layer of 

compacted rubble.

Economics of Recycling

Concrete recycling has proven to be profitable, but its use has 

limitations. Transportation costs need to be kept low, which forces the 

market to be urban-oriented. The market for recycled aggregates may 

be restricted by user specifications and prejudices. Finally, the 

availability of feedstock into recycling plants is fixed by the amount of 

demolition taking place, which generally places the activity within 

older, larger cities.

Depending on the size of the recycling facility, entry into the 

aggregates recycling business requires a capital investment between 

$4.40 and $8.80 per metric ton of annual capacity (Wilburn and 

Goonan, 1998).

Processing costs for the aggregates recycler range from $2.76 to 

$6.61 per metric ton, again depending on the size of the operation. 

The larger operations distribute costs over more units of output. The 

average production capacity for a fixed site recycling operation is 

about 150,000 t per year.

Prices (1999) for the various aggregate products made from 

recycled concrete range between $1 and $18 per metric ton and vary 

from region to region. The highest prices are in aggregate-poor areas 

of the southern United States.

Recyclers often have the opportunity to charge a fee for accepting 

concrete debris, especially along the Atlantic corridor where landfill 

space is running short and charges for depositing materials into 

landfills are high. In such cases, the added revenue can compensate for 

a lower market price for the recycled aggregate product. As natural 

aggregate producers dominate the market, they tend to set the terms that 

recyclers can obtain.

The Future for Concrete Recycling

The future for recycled aggregates will be driven by reduced 

landfill availability, greater product acceptance, continuing government 

recycling mandates, and the continuing decay of a large stock 

of existing infrastructure, as well as by the demands of a healthy 

economy.

Summary

The recycling of aggregates from recovered asphalt pavement and 

demolished concrete debris conserves resources and landfill space, while 

also generating healthy profits for recyclers. Recycling can take place 

either at a permanent facility or at the demolition site, using mobile 

equipment.

A sustainable recycling industry requires numerous factors, including 

sufficient concrete and asphalt decay and demolition to supply the 

recycler with raw materials, demand for new infrastructure, favorable 

transportation distances, product acceptance, and limited landfill space.

Information Sources

Bolen, W.P., 1999, Sand and gravel (construction): U.S. Geological 

Survey Mineral Commodity Summaries 1999, p. 146–147.

Deal, T.A., 1997, What it costs to recycle concrete: C&D Debris 

Recycling, September/October, p. 10–13.

Kelly, T.D., 1998, The substitution of crushed cement concrete for 

construction aggregates: U.S. Geological Survey Circular 1177, 15 p. 

Available only online at URL 

http://greenwood.cr.usgs.gov/pub/circulars/c1177/

Tepordei, V.V., 1999, Stone (crushed): U.S. Geological Survey Mineral 

Commodity Summaries 1999, p. 162–163.

Wilburn, D.R., and Goonan, T.G., 1998, Aggregates from natural and 

recycled sources: U.S. Geological Survey Circular 1176, 36 p. 

Available only online at URL

 http://greenwood.cr.usgs.gov/pub/circulars/c1176/

For Additional Information Consult:

http://minerals.usgs.gov/minerals

Or contact:

Minerals Information Team

(703) 648-4911

Thomas G. Goonan

U.S. Geological Survey

Box 25046, M.S. 750

Denver Federal Center

Denver, CO 80225

(303) 236-8747 × 228

goonan@usgs.gov