AASHTO specification

During the 1920s the following three national specifications for asphalt cements were pubHshed (/) Federal specifications, adopted in 1925 (2) the American Association of State Highway Transportation Officials (AASHTO) specifications, adopted in 1924, revised in 1926 and (2) ASTM specifications, adopted in 1922 to 1926, withdrawn in 1939, and re-issued in 1947. 

The Federal specifications stipulated that only those asphalts that had been demonstrated by service tests as satisfactory for the intended use would be accepted. The specifications also indicated the type and location of constmction and the relative amount of traffic for each of the grades. The AASHTO specifications indicated that the use of each grade depended on the type of road, climate, and traffic. The ASTM suggested the type of constmction for which each grade would be used. 

The vessel collision design recommendations provided in this chapter are consistent with the AASHTO specifications (AASHTO 2009, 2012), and they apply to all bridge components in navigable waterways with water depths over 2.0 ft (0.6 m). The vessels considered include merchant ships larger than 1000 DWT and typical inland barges. 

At the front face of stem, using 5 12 in. in both longitudinal and horizontal direction, it meets the crack control requirements of the AASHTO specifications. 

ASTM D7409 provides the standard test method for the CEG content of PET yams. The test is conducted by dissolving PET yams in o-cresol at 80°C. The solution is diluted with dichloromethane, and titrated against KOH dissolved in methanol by either a potentiometric or colorimetric method. The amount of potassium hydroxide required to complete the titration with the PET solution is measured and used to calculate the concentration of CEGs. The test method determines the concentration in mmol/ Kg of CEG found in the yams and is expressed in equivalents per million grams. Per AASHTO specifications, sometimes a maximum value of 30 is required for PET used in geotextiles. 

Standard Specification for Sodium Chloride AASHTO M143-94 American Association of State Highway Transportation Officials... 

Portland cements are manufactured to comply with specifications estabUshed in each country (70). In the United States, several different specifications are used, including those of the American Society for Testing and Materials and American Association of State Highway and Transportation Officials (AASHTO). The ASTM aimuaHy pubhshes test methods and standards (24), which are estabhshed on a consensus basis by its members which include consumers and producers. 

Source From AASHTO, AASHTO Designation M240 Blended hydraulic cements, in Standard. Specification for Materials, American Association of State Highway and Transportation Officials, 1986. 

AASHTO M85 Standard Specification for Portland Cement, www.cement.org... 

With constant updates in the American Association of State Highway and Transportation Officials (AASHTO) and American Society for Testing and Materials (ASTM) specifications for epoxy-coated rebar, this corrosion protection system will continue to improve. The specifications involve all aspects of fabrication of epoxy-coated rebar. All these will result in improved performance of epoxy-coated rebar and more durable new concrete stmctures. 

AASHTO-AGC-ARTBA (1993). Guide Specification for Cathodic Protection of Concrete Bridge Decks, Task Force 29, Federal Highway Administration,... 

Publishes AASHTO/ARTBA/AGC Guide Specifications for reinforced concrete construction and repair of highway structures... 

The representative size of the particles for the above groups and subgroups differs slightly from one specification to another. The representative size of the particles for the above fractions and subfractions in accordance with CEN EN ISO 14688-1 (2013), AASHTO M 146 (2012) and ASTM D 2487 (2011) standards are shown in Table 1.1. 

However, details regarding laboratory investigation of density and specific gravity of soils can be found in CENISO/TS 17892-3 (2005), ASTM D 854 (2010) or AASHTO T100 (2010). 

The CBR laboratory test can be carried out by ASTM D 1883 (2007), AASHTO T 193 (2013) or CEN EN 13286-47 (2012) other equivalent national specifications may have been developed. 

The extensive Strategic Highways Research Program, completed in the United States in 1993, concluded in performance graded (PG) specifications for bitumens (asphalt binders) known as Superpave (superior performing pavements) specification. These specifications were first introduced by Asphalt Institute (Asphalt Institute SP-1) and soon became an AASHTO standard (AASHTO M 320) and ASTM standard (ASTM D 6373 2007). 

During the ductility test, the bitumen specimen is pulled apart at a specified speed and temperature condition (50 mm/min, 25°C) until it ruptures or reaches the length limitations of the machine. The elongation length at rupture, measured in centimetres, is defined as the bitumen s ductility value. The test is performed on three briquette specimens and the average of the three values is determined. In the event of discrepancy of results, they should be within the acceptable range set by the specification (AASHTO T 51 2009 ASTM D 113 2007). 

The flash and fire temperatures calculated under ambient barometric pressure are corrected for normal atmospheric pressure, 101.3 kPa, using a correction equation provided by the specification. A detailed description of the test can be found in CEN EN ISO 2592 (2001), ASTM D 92 (2012) or AASHTO T 48 (2010). 

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