Properly sealed cracks have been proven to improve sealant life by 7+ years and extend pavement service life by an additional 2-5 years. Research has shown that by reducing cracking distresses in a road leads to a reduction in potholes and cracking from 75% to 1% within three years. Also properly treated and sealed crack has been proven to maintain pavement smoothness over a five year period as well as a reduction in raveling.

In addition to the pavement performance crack sealing makes a difference in the community as it makes every highway dollar count preventing potholes and other pavement distresses. Crack routing and sealing is inexpensive and adds marginal costs to other types of preservation treatment and significantly extends the service life of the pavement. It has the lowest average cost over a four year period than any other form of pavement treatment.

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October/November 2016.Pavement.www.forconstructionpros.com/pavement  
Smith,K.L., and A.R. Romine. 1999a materials and procedures for sealing 
and filling cracks in asphalt-surfaced pavements.Morian, D.A. Gibson, 
S.D, and Epps, J.A. March 1998. Maintaining Flexible Pavements.