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From page 13... ... Additionally, 11 responses noted the use of empirical methods based on an agency's past experience, and 4 agencies claimed to use no formal method. The Canadian sample was similar; 4 of 8 respondents reported using the ISSA A143 method (2010b) Read the entire page →
From page 14... ... Agency in-house design section 2 1 Agency in-house maintenance group 2 0 Agency in-house materials lab section 1 1 Microsurfacing contractor under the construction contract 21 6 Independent lab for the microsurfacing contractor under the construction contract 1 0 Do not know 1 0 TABLE 6 JOB MIX FORMULA DEVELOPMENT RESPONSIBILITY SUMMARY Agency Microsurfacing Warranty Length Warranty Criteria Louisiana 1 year Standard construction warranty for surface defects New Hampshire 1 year Surface defects New York 1 year Raveling, flushing, delamination, snowplow damage Oklahoma 1 year Standard construction warranty for surface defects Alberta 1 year Raveling British Columbia 1 year Standard construction warranty for surface defects Quebec 1 year Standard construction warranty for surface defects Saskatchewan 1 year Standard construction warranty for surface defects Nevada 2 years Standard construction warranty for surface defects Texas 2 years Raveling, flushing Manitoba 2 years Raveling, friction New Brunswick 2 years Standard construction warranty for surface defects Nova Scotia 2 years Standard construction warranty for surface defects Ontario 2 years Raveling, flushing Indiana 3 years Raveling, friction, rutting TABLE 7 MICROSURFACING WARRANTY SUMMARY Performance Rating Excellent Good Fair Poor Very Poor U.S. 1 20 4 0 0 Canada 1 7 0 0 0 Total 2 27 4 0 0 TABLE 8 MICROSURFACING PERFORMANCE RATINGS Read the entire page →
From page 15... ... ; MIII = Microsurfacing (Type III) ; S = Slurry Seal Surface Condition Maintenance issues Type Pavement Condition Rutting Traffic VolumesCracking E x p e c t e d s e r v i c e l i f e MII F G N G N N N N G G G F G F G G G G F G MIII - G G N G G P N N G G G F G F G G N N F F M G G G - G G N N N G G - - - - - - - - - S - G G - N N P N N - - - - - - - - - - - - S - G - - - - F P P - - - - - - - - - - - - M G G - G G G N N N G G G - - G - - - S F G - G G G N N N G P N - - F - - - M G G G G G G - - - - - - - - - - - - - - M - F - - G G P P P G G G - - - - - - - - - S - P - - P P P P P G N N - - - - - - - - - M G G G - F F P F F - - - - - - - - - - - - S G F F - - - P P P - - - - - - - - - - - - M G G G G G G F G G G G G - - G G G G G - G S G G N G F N N P F G G G - - G G N N N - N MII - G G G G G N N N G G G G G - - - - - G MIII - G G G G G N N N N G G G G - - - - - G M - - - - G G - - - G G G G - - G G G G G G S - - - - N N - - - G N N - - - N G N N - - M G - - - G G P P P G G G - - - F G G G - G S F - - - F N N N N F N N - - - G N - - - - M - G G G G G F F F G G F - - - G F M G - G F G G F F F G G G - G - G G G G - M G - G G G G F F F G G G G G - G G G G G G S G - F F - - P P P G G G N - - G - N N N P 3 TO 4 3 TO 4 3 TO 8 2 TO 6 7 TO 10 7 TO 10 7 TO 10 5 TO 7 5 TO 6 5 TO 7 M G F G G G G F P P - - - - - P - - - - - - AI = Asphalt Institute. Read the entire page →
From page 16... ... The process necessitates that those candidates be evaluated as a group and R ec om m en da tio n Fr ict io n Ra ve lin g Ox ida tio n Bl ee din g < 1 /2 " > 1/ 2" Al lig at or Lo ng itu din al Tr an sv er se AD T< 3K AD T = 3K to 5 K AD T >5 K Co ol Te m ps St op pin g Po int s Sn ow p low u se Ur ba n Ru ra l Ea rly O pe nin g to T ra ffic M ul tip le Lif ts Ne ed ed Ni gh t-t im e W or k M in im ize U se r D ela y C os ts Good Fair Sum1 Poor Not Sum2 Net 9 8 1 12 13 11 4 0 2 9 6 0 0 0 9 9 3 12 0 0 0 12 12 0 12 0 0 0 12 1 9 0 2 2 15 1 16 0 0 0 7 16 14 1 15 0 1 1 0 5 5 4 5 9 4 5 3 6 9 14 -4 -4 1 4 5 3 6 9 0 12 0 1 1 0 13 0 0 0 1 12 0 0 0 -4 11 13 12 6 0 0 0 6 6 0 0 0 0 6 4 2 2 1 0 1 3 8 7 1 0 0 0 8 8 7 1 0 0 0 8 6 6 0 0 1 1 5 6 6 0 0 1 1 5 6 4 2 0 0 0 6 6 5 1 0 0 0 6 Cracking TypeMaintenanceIssues Traffic VolumesPavement Condition Rutting Desired Benefits TABLE 10 QUANTIFIED OUTPUT FOR MICROSURFACING ONLY FROM TABLE 9 Read the entire page →
From page 17... ... Rut filling will generally consist of a rut filling course followed by a full lanewidth surface course. Therefore, it is one of the few pavement preservation and maintenance treatments that can restore the transverse geometry of a rutted road. Read the entire page →
From page 18... ... It shows that when friction loss is localized that mechanical retexturing using shotblasting or diamond grinding will be more cost-effective than microsurfacing. However, as the magnitude of the unsafe area increases, microsurfacing becomes the preferred option based on a lower production cost and reduced user-delay costs (Berg et al. Read the entire page →
From page 19... ... This research demonstrates the potential for microsurfacing to quickly and effectively enhance the surface friction of a structurally sound pavement that has become unsafe owing to polishing of its aggregate or the loss of macrotexture resulting from flushing or bleeding. The FHWA issued a technical advisory on pavement friction management (FHWA 2010b) Read the entire page →
From page 20... ... One side advocated the use of bituminous surface treatments as pavement preservation tools and opined that because the consumption of raw materials and energy by microsurfacing was decidedly less than that of a hot-mix asphalt overlay that the treatment inherently had less impact on the environment (Takamura et al. 2001; Uhlman 2010) Read the entire page →
From page 21... ... It is important that each of these ingredients be compatible with each other for the microsurfacing to work as designed. Therefore, the mix design process is necessarily based on laboratory results, which are in turn used to optimize the job mix formula. Read the entire page →
From page 22... ... However, there is a low effective limit to the amount of reflective cracking microsurfacing will resist. Finally, the polymers permit microsurfacing to be placed in thicker sections of two to three stones thick, which enables its use in rut filling. Read the entire page →
From page 23... ... The primary difference between the two gradations is top size, with Type III furnishing a coarser aggregate than Type II. The gradation determines the appropriate amount of residual asphalt in the mix design as well as the particular applications, such as rut filling, for which a given mix design is effective. Read the entire page →
From page 24... ... 16 11 6 Canada 2 7 1 Total 18 18 7 Content Analysis Total 7 6 8 Grand Total 25 24 15 TABLE 18 MICROSURFACING AGGREGATE GRADATIONS (ISSA 2010b) AND USAGE FOUND IN THE SURVEY Mineral fillers found in the study: • Portland cement • Hydrated lime • Limestone dust • Crushed rock screenings • Fly ash • Kiln dust • Baghouse fines Additives found in the study: • Aluminum sulfate crystals, • Ammonium sulfate • Inorganic salts • Liquid aluminum sulfate, • Amines • Anti-stripping agents Read the entire page →
From page 25... ... Table 20 contains the guidance found in an ISSA manual. However, it does have a maximum limit for Type III of 30 pounds per square yard (18.3 kg/m2) Read the entire page →
From page 26... ... Wheel Ruts As required (see below) Type III Scratch or Leveling Course As required Rut Depth Application Rate 0.5–0.75 in. Read the entire page →
From page 27... ... Effective Practices 1. Project selection is critical to microsurfacing success and those agencies that only apply microsurfacing to structurally sound pavements are generally satisfied with its performance. Read the entire page →

From page 13...

... Additionally, 11 responses noted the use of empirical methods based on an agency's past experience, and 4 agencies claimed to use no formal method. The Canadian sample was similar; 4 of 8 respondents reported using the ISSA A143 method (2010b)