## Chapter 620 Design of Pavement Structure

Consider the inclusion of crushed surfacing top course material for keystone when estimating ... and if the grading contains more than 45% sand, the factor would decrease, approaching 3,400 lb/cy (1.70 tons/cy) for material that is essentially all sand. ... Chapter 620 Design of Pavement Structure WSDOT Design Manual M 22-01.12 Page 620-3