Where can you find drainage coefficients and moisture exposure percentages for pavement structures?

• A. AAHSTO 1993 PDG
• B. AASHTO 1993 PDG
• C. Transportation Research Board Handbook
• D. National Cooperative Highway Research Program

Answer: (B)

The correct choice is B because AASHTO, which stands for the American Association of State Highway and Transportation Officials, published the 1993 Pavement Design Guide (PDG). This guide specifically includes information on the design of flexible and rigid pavements and provides essential criteria such as drainage coefficients and moisture exposure percentages, which are pivotal for ensuring proper pavement performance and longevity.

The AASHTO 1993 PDG lays out standardized methodologies and tables, which practitioners rely on when assessing how moisture conditions might affect pavement structures. Understanding these coefficients is crucial for engineers to consider the influence of drainage on pavement stability and performance.

Other sources like the Transportation Research Board Handbook or the National Cooperative Highway Research Program may contain relevant information but do not specifically focus on the drainage coefficients or moisture exposure percentages for pavement design in the same comprehensive way as the AASHTO guide does. The AAHSTO reference seems to be a typographical error or confusion, as the standard reference is AASHTO. Therefore, selecting AASHTO 1993 PDG is appropriate when looking for detailed pavement design guidance.