TACK, AND ASPHALT SURFACE TREATMENTS
403.01 Mineral Aggregate. The various classes of Mineral
Aggregate shall conform to the grading requirements of Subsection 403.02. Composition shall be as follows : 239 Class 1, Class 2, and Class 4 shall be crushed stone, crushed gravel, or crushed steel slag in which at l east 90% by weight of the coarse particles have been produce d from larger particles by crushing operations and shall c ontain no more than 5% novaculite. Class 3 shall be crushed or uncrushed gravel, crushed stee l slag, or crushed stone. Class 5 shall be composed of material meeting the requirements of either Class 1, Class 2, or Class 3 at the option of the Contractor. Crushed stone shall consist of tough durable fragme nts of rock of uniform quality, and shall not contain more than 5% soft particles (AHTD Test Method 302). When subjected to 5 cycles of the Sodium Sulfate Soundness Test (AASHTO T 104), it sh all have a loss not to exceed 12% and shall have a percent of wear by the Los Angeles Test (AASHTO T 96) not greater than 35. Gravel shall consist of hard, durable aggregate and shall not contain more than 5% soft particles (AHTD Test Meth od 302) and shall have a percent of wear by the Los Angeles Tes t (AASHTO T 96) not greater than 35. Steel slag shall consist of hard, durable aggregate and shall not contain more than 5% soft particles (AHTD Test Meth od 302). When subjected to 5 cycles of the Sodium Sulfate So undness Test (AASHTO T 104), it shall have a loss not to exceed 12% and shall have a percent of wear by the Los Angeles Test (AAS HTO T 96) not greater than 35. Fine aggregate is that portion passing the #10 (2.0 0 mm) sieve, and shall consist of clean, sound, hard, and durabl e particles of natural sands, stone sand, and other inert substanc es of similar characteristics. Coarse aggregate is that portion retained on the #10 (2.00 mm) sieve. All mineral aggregates shall be uniformly well grad ed from coarse to fine and free from lumps or foreign mater ial. They shall also be free from adherent films of clay that will prevent thorough coating with asphalt material.
403.02 Aggregate Gradation. Requirements in the following
table are given in percent passing by weight. 240 Class Sieve, (mm) 3/4" 1/2" 3/8" #4 #10 #16 (19.0) (12.5) (9.5) (4.75) (2.00) (1.18) 1 100 90-100 -- 0-15 0-3 -- 2 -- 100 80-100 -- 0-15 0-3 3 -- 100 80-100 -- 0-15 0-3 4 -- -- 100 50-90 0-15 0-8 5 May be either Class 1, 2, or 3. Sieve analysis will be determined by AASHTO T 27. The decantation loss as determined by AASHTO T 11 s hall not exceed 1.5% for any class of mineral aggregate.
403.03 Asphalt Materials. Asphalt materials shall include cut-
back asphalt, emulsified asphalt, and asphalt binde r. Samples of asphalt material will be tested according to applic able AASHTO or ASTM methods.
a.Rapid Curing Cut-back Asphalt. Rapid Curing Cut-back Asphalt shall conform to the requirements of AASHTO M 81.
b.Medium Curing Cut-back Asphalts. Medium Curing Cut- back Asphalt of the grade designated shall conform to the requirements of AASHTO M 82.
c.Anionic Emulsified Asphalt. Anionic Emulsified Asphalt shall conform to the requirements of AASHTO M 140.
d.Cationic Emulsified Asphalt. Cationic Emulsified Asphalt shall conform to the requirements of AASHTO M 208. In addition, CRS-2 shall have: 1) A minimum Saybolt Furol Viscos ity at 122° F (50° C) at the point of manufacture and/or origin o f 200 seconds, and a maximum Saybolt Furol Viscosity of 500 second s. The Saybolt Furol Viscosity at 122° F (50° C) on destin ation field samples shall be within the limits of 100-500 secon ds. If the asphalt fails to comply at 122° F (50° C) test temperature, the test shall be repeated at 160° F (70° C) and shall be within the limits of 90-200 seconds; and 2) the minimum residue from distillati on by weight shall be 68%.
e.Polymer/Latex Modified Cationic Emulsified Asph alt. Polymer Modified (CRS-2P) and Latex Modified (CRS-2 L) Cationic Emulsified Asphalt shall conform to the re quirements of AASHTO M 316, except for the minimum Ductility at 2 5 ° C (77 ° 241 F). In addition, CRS-2P and CRS-2L shall have : 1) A minimum Saybolt Furol Viscosity at 122° F (50° C) at the po int of manufacture and/or origin of 200 seconds, and a max imum Saybolt Furol Viscosity of 500 seconds. The Saybolt Furol Viscosity at 122° F (50° C) on destination field samples shall b e within the limits of 100-500 seconds. If the asphalt fails to comply at 122° F (50° C) test temperature, the test shall be repeated at 160 ° F (70° C) and shall be within the limits of 90-200 seconds; 2) th e minimum residue from evaporation by weight shall be 68%, and 3) the penetration on residue from evaporation test shall be a maximum of 250.
f.Asphalt Binder. Asphalt binder furnished shall conform to the requirements of AASHTO M 320 Table 1, except th e Direct Tension requirement is deleted.
403.04 Application Temperatures. Asphalt material shall be
applied at a temperature that provides proper and u niform distribution and within practical limits avoiding h igher temperatures than necessary. Satisfactory application usually s hould be obtained within the recommended ranges shown below. No mate rial shall be heated above the maximum allowable temperatures sho wn: Recommended Range Maximum Allowable Type and Grade °F °C °F °C RC-70 80-150 27-66 175 80 RC-250 100-175 38-80 200 93 RC-800 160-225 71-107 250 121 RC-3000 200-275 93-135 290 143 MC-30, MC-70 80-150 27-66 175 80 MC-250 100-200 38-93 230 110 MC-800 185-260 85-127 275 135 MC-3000 225-275 107-135 290 143 RS-1, RS-2 125-185 52-85 185 85 242 Recommended Range Maximum Allowable Type and Grade °F °C °F °C MS-2 70-160 21-71 160 71 SS-1, SS-1h 70-160 21-71 160 71 CRS-1, CRS-2, CRS-2P, CRS-2L 125-185 52-85 185 85 CMS-2h, CMS-2 70-160 21-71 160 71 CSS-1, CSS-1h 70-160 21-71 160 71 All Asphalt Binders 275-325 135-163 350 177 Note: Heating of asphalt materials (except emulsio ns) constitutes a fire hazard to various degrees. Proper precautio ns should be used in all cases and especially with rapid curing cut-b acks, as the maximum allowable temperature may exceed the flash point.
403.05 Heating Equipment. Equipment for heating asphalt
material in tank cars or storage tanks shall have a dequate capacity to heat the material by steam coils, electricity, or o ther means such that no flame shall come in contact with the heating tan k. The heating equipment shall be provided with an acc urate thermometer to indicate the temperature of the asph alt material in the unit to which heat is being applied. Heating e quipment that agitates the material will be prohibited if, in the opinion of the Engineer, it injures or in any way changes the char acteristics of the material. The introduction of free steam directly into asphalt material will not be permitted.
403.06 Pressure Distributors. Each pressure distributor used
for applying asphalt material shall be equipped wit h the following listed appliances or devices:
1.Tachometer devices registering traveling speed i n feet per minute (meters per minute) or feet per second (mete rs per second).
2.A gauge, indicating pump pressure or output in g allons per minute (liters per minute) or gallons per second (l iters per second) passing through the nozzles. 243 3) Thermometer well and accurate thermometer to ind icate the temperature in degrees Fahrenheit (Celsius) of the asphalt material in the distributor.
4.Spray bars shall be of adjustable length and hei ght and the distributor shall produce a 50% lap of the sprays f rom adjacent nozzles.
5.A power unit and pump system that will supply a uniform pressure through the entire length of the spray bar to provide equal output from all nozzles.
6.Calibrated metal measuring stick, marked in incr ements of not more than 10 gallons (50 L).
7.Easily removable dome cover.
8.Wind guard on ends of spray bars. Calibration of the distributor will be checked by t he Engineer before being used on the work. Distributors previo usly calibrated as described above by the Department or by another sta te Department of Transportation or the manufacturer, and certifie d in writing, will be accepted. Distributors will be kept free from s ludge or other residue and at any time there is evidence of inaccu racy they will be subject to re-calibration. The Contractor shall pr ovide, at no cost to the Department, all necessary equipment, materials, and assistance for any required calibration.
403.07 Aggregate Spreaders. The mechanical spreader for
mineral aggregate shall be self-propelled and capab le of accurately and uniformly spreading the material. Calibration of the spreader will be checked by the Engineer prior to the actual work, and as often as necessary, to a ssure that the openings are properly set to feed the aggregate at the designated application rate.
403.08 Rollers. (a) General. Rollers shall be equipped with
approved devices to prevent adhesion of the surfaci ng material to the wheels. Rollers shall be maintained in good me chanical condition and operated to produce a surface course with satisfactory aggregate orientation and interlock. Rollers shall be equipped with a self-contained power unit adequate to maintain depe ndable forward and reverse working speeds. Rollers shall have a s ystem for cleaning the tires for the full width of each tire. 244 (b) Pneumatic Rollers. Pneumatic rollers shall be mounted on 7 or more wheels, a minimum of 3 leading wheels and 4 drive wheels. The wheels shall be mounted at right angles to the axles, shall maintain this position through the full revolution, and shall afford a continuous and complete rolling width of not less t han 60 inches (1.5 m). The tires shall have a smooth tread. All tires on an individual roller unit shall be of equal size and d iameter and shall be so arranged that the gap between the tires of one a xle is covered by the tires of the other axle. Tires shall be unifor mly inflated so that the air pressure of the several tires shall not var y more than 5 psi (35 kPa). Pneumatic rollers shall be capable of exerting a mi nimum ground contact pressure of 45 psi (310 kPa). The Contract or shall furnish to the Engineer charts or tabulations showing the cont act area and contact pressure for the full range of tire inflati on pressures and for the full range of tire loadings for each type and s ize compactor tire furnished. The tires shall be inflated and the rol ler loaded with ballast, as required, to obtain the average ground contact pressure necessary to obtain proper compaction.
c.Steel Wheel Rollers. Steel wheel or combination steel wheel/pneumatic rollers may be either three wheel o r tandem type, shall weigh not less than 200 pounds per inch (35 k g/10 mm) width of roller, and shall have a complete rolling width of not less than 36" (1 m).
Source: , Edition.