22-06-2012, 02:59 PM
Superpave Binder Purchase Specification
[attachment=25095]
Pavement Design Concepts
Perhaps the most widely used pavement design method used in the United States and throughout
the world is that presented in the AASHTO Guide for Design of Pavement Structures.
A long history of pavement studies has lead to the current (1993) edition. The ODOT method for the design of pavement structures is almost identical to the AASHTO method, but ODOT has simplified some parts of the AASHTO Guide since it needs to apply only to the conditions encountered in Ohio.
The AASHTO / ODOT pavement design equations have some variables that are common to both rigid and flexible pavement, including: serviceability, traffic loading, reliability, overall standard deviation, and roadbed soil resilient modulus. The remaining variables needed for the design of a pavement structure are presented in the respective rigid and flexible pavement sections on design procedures.
Pavement Design Concepts
201 Serviceability
ODOT’s Pavement Design Method (AASHTO) is developed around the concept of serviceability,
which serves as the pavement performance parameter by which a pavement’s condition is valued. Serviceability is defined as the ability of a pavement to serve traffic. The Present Serviceability Rating (PSR) was developed to measure serviceability. PSR is a rating of pavement ride based on a scale of 0, for impassible, to 5, for perfect. For the development of the original AASHTO Pavement Design Equation, individuals (the raters) would ride the pavements and assign a PSR value. To avoid riding and rating every pavement by all raters to determine serviceability, a relationship between PSR and measurable pavement attributes has been developed. This relationship is defined as the Present Serviceability Index (PSI).
[attachment=25095]
Pavement Design Concepts
Perhaps the most widely used pavement design method used in the United States and throughout
the world is that presented in the AASHTO Guide for Design of Pavement Structures.
A long history of pavement studies has lead to the current (1993) edition. The ODOT method for the design of pavement structures is almost identical to the AASHTO method, but ODOT has simplified some parts of the AASHTO Guide since it needs to apply only to the conditions encountered in Ohio.
The AASHTO / ODOT pavement design equations have some variables that are common to both rigid and flexible pavement, including: serviceability, traffic loading, reliability, overall standard deviation, and roadbed soil resilient modulus. The remaining variables needed for the design of a pavement structure are presented in the respective rigid and flexible pavement sections on design procedures.
Pavement Design Concepts
201 Serviceability
ODOT’s Pavement Design Method (AASHTO) is developed around the concept of serviceability,
which serves as the pavement performance parameter by which a pavement’s condition is valued. Serviceability is defined as the ability of a pavement to serve traffic. The Present Serviceability Rating (PSR) was developed to measure serviceability. PSR is a rating of pavement ride based on a scale of 0, for impassible, to 5, for perfect. For the development of the original AASHTO Pavement Design Equation, individuals (the raters) would ride the pavements and assign a PSR value. To avoid riding and rating every pavement by all raters to determine serviceability, a relationship between PSR and measurable pavement attributes has been developed. This relationship is defined as the Present Serviceability Index (PSI).