Pavement Preservation Journal - Summer 2013 - (Page 34)

CENTERS In Texas, Fog Seals Should Last 18 Months By Yetkin Yildirim, P.E. T he mission of the Texas Pavement Preservation Center (TPPC) is to promote the use of pavement preservation strategies. To this effect, TPPC expands upon the use of fog seals in its current newsletter by detailing their advantages and disadvantages in maintaining roadways. Fog seals consist mainly of a diluted asphalt binder that is applied directly to the pavement surface. The main types of binders used in fog seals are cutbacks, emulsions, and polymer-modified emulsions. Fog seal materials used in Texas generally have a wide range of properties, but most are water-based emulsion materials. A fog seal is applied directly to a pavement surface in spray form. When used properly on porous surfaces, fog seals can seal the pavement, lengthen the pavement surface life, provide some pavement edge-shoulder delineation, and prevent raveling. They also can be used during seal coat applications as a flush coat, which holds aggregate in place and protects windshields from flying rocks. The preventive maintenance of existing roadways, as opposed to the construction of new ones, has gained momentum in the United States. Fog seals have been a cost-effective means of preventive maintenance in Texas and other states for many years. WHEN TO USE A FOG SEAL Fog seals function properly only when they achieve penetration. Because of this, fog seals should be used on aged and raveled hot-mix surfaces and chip-sealed surfaces. Fog seals have three main functions: to prevent raveling, to preserve and protect road conditions, and to seal and treat cracking and surface defects. Therefore, fog seals should be used only on structurally sound pavements with minor defects. Fog seals decrease AN INTERNATIONAL DISTRIBUTOR OF FIBER PRODUCTS FREE Volumetric Fiber Dispenser For Slurry Seal & Micro Surfacing Call or Email for details. 1-941-342-9997 34 View past issues of the Pavement Preservation Journal online at 637036_VM.indd 1 23/04/13 11:00 PM

Table of Contents for the Digital Edition of Pavement Preservation Journal - Summer 2013

President’s Message
‘Thinning Up’ Concrete Overlays for Pavement Preservation
IGGA: After Five Years, Colorado CPR Project Holds Strong
Joint Meeting Brings ARRA, ISSA, AEMA to California Desert
At NCAT Preservation Study, Performance Clues Emerge
Integrated System Keeps Fort Collins ‘Asset Smart’
New Alaska Database Aids Treatment Selection
GPR, FWD Analyze Airfi eld Pavements in South Carolina
TPPC: In Texas, Fog Seals Should Last 18 Months
Caution Due in Using MC-30 as Prime Coat
In Nevada, Cold Recycling Preserves I-80
Index of Advertisers

Pavement Preservation Journal - Summer 2013