Chip Seal Best Practices (2005) / Chapter Skim
Currently Skimming:
Appendix C - Chip Seal Design Details
Appendix C - Chip Seal Design Details
Pages 100-108
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 100... ...
The Asphalt Emulsion Manufacturers Association and the Asphalt Institute have gone on to adapt this method in the form of recommendations for binder types and grades for various aggregate gradations, and correction factors to the binder application rate based on existing surface condition (Seal Coat .
|
From page 101... ...
All of their tests were conducted under the same conditions, with only the test parameter being variable. Those FIGURE C1 Nomograph to determine asphalt cement application rate in seal coats and onecourse surface treatments (Kearby 1953)
|
From page 102... ...
Since the publication of that design procedure, the Texas Department of Transportation's Brownwood District has expanded on the asphalt application correction factors to include adjustments for truck traffic and existing surface condition. Table C2 shows the design output that was used in a research study documenting chip seal performance on highvolume roads in Tulsa, Oklahoma, in 1989 (Shuler 1991)
|
From page 103... ...
Aggregate angularity, traffic volume, road geometry, ALD of aggregate, aggregate absorption, pavement absorption, and texture depth are the input variables for this TABLE C2 COMPARATIVE DESIGN OUTPUT FOR THE MODIFIED KEARBY AND McLEOD CHIP SEAL DESIGN METHODS Existing Surface Condition Slight Bleeding Normal Slight Raveling Design Method Nominal Aggregate Size Modified Kearby McLeod Modified Kearby McLeod Modified Kearby McLeod Emulsion Rate (gal/yd2) Emulsion Rate (gal/yd2)
|
From page 104... ...
Refers to paragraph in design manual that governs the specific aspect of chip seal design in that row of the table. Source: Design Guide for Road Surface Dressings 1996.
|
From page 105... ...
It should be noted that some of the allowances may be negative, and thus the design binder application rate may be lower than the base binder application rate. For multiple course chip seals, the Austroads design methodology distinguishes between whether the additional courses are applied immediately or later.
|
From page 106... ...
Another important assumption of this design method is including correction factors to adjust binder application rates when using modified binders. Polymer-modified binder application rates are adjusted, because the South Africans have found that aggregate orientation is different in comparison with conventional seals.
|
From page 107... ...
28 500 Ch. 62 800 to / na : TRH 3 1998 Northbound and Southbound Slow lane Approved by/date: Checked by/date: Prepared by/date: dolorite, precoated @ 14 l/m3 with sacrasote 70 or similar approved 19,0mm 6,7mm 12,2mm 4,5mm FIGURE C4 South African TRH3 chip seal design method sample.
|
From page 108... ...
Control check (Alternative design Methods) Spray rates FIGURE C4 (Continued)
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.