Cement-Treated Base

Similar to the unstabilized base, cement-treated base is typically placed using an asphalt or concrete spreader on the grade and compacted with rollers. The following summarizes best practices regarding construction of cement-treated bases:

• Due to the nature of the cement, the available time to placing, compacting, and trimming of the cement-treated base is limited to approximately 4 hours after the cement is mixed with water. Other factors,such as wind and heat, may further limit the available working time.
• The surface of the trimmed base should be within ± ½ inch of the design profile grade.
• After finishing, the base requires curing application with a light fog spray of water or a bituminous curing agent at a rate of 0.15 to 0.25 gal/yd2.
• If trimming of cement-treated base is unavoidable just before paving of the PCC,the surface should be treated to prevent bonding of the base to the PCC. The applicable bond breakers include (1)reapplication of the bituminous curing agent with a thin layer of sand or (2) application of two coats of wax-based curing compound.