Method of protecting pavement from corrosive salts and an impermeable pavement membrane and pavement overlay for use in said method (US Patent 3,870,426, 1975)

John Howard Kietzman and Mario Peter Tocci received US Patent No. 3,870,426 on March 11, 1975, filed September 10, 1973. It was assigned to Johns Manville.

The patent's abstract:

Salts used on highways and bridges to melt snow and ice combine with the melted snow or ice to form corrosive solutions which attack the pavement and the steel reinforcement therein causing severe deterioration. A method has been discovered for sealing the top surface of pavements to prevent the penetration of such corrosive salts thus eliminating the problem of deterioration. The method utilizes an impermeable membrane comprising asbestos fibers, asphalt and relatively fine aggregate. This membrane may be in the form of preformed sheets or it may be laid down on the site as a hot mix using conventional paving machines. An asphalt concrete wearing course is applied over the membrane and the heat from said wearing course and the rolling compaction of the wearing course cooperate in rendering the membrane impermeable. The method requires a minimum effort in preparing the pavement for the sealing membrane, requires a minimum of time to complete and thus a minimum in traffic delay and offers a further advantage in that the membrane itself can be driven on temporarily to relieve traffic congestion prior to the application of the wearing course. This method has proven especially advantageous in protecting portland cement concrete pavements in bridge decks from deterioration.

Where it was listed

• Asbestos, July 1975, in its patents department (the year's issues)