Stabilization of Poor Quality Aggregate. Th 30 Near Mapleton

摘要

This report concerns the design, construction and evaluation of a 7 1/2 mile project featuring portland cement, lime and asphalt emulsion stabilization of a poor quality aggregate. Base thicknesses of 6, 8, and 10 in-stabilized by 2, 4 or 9 percent cement, 1.5, 2.5 or 5.5 percent asphalt emulsion, or 3 percent lime were studied. The effects of delayed compaction on the performance of several lime treated and cement modified (2 or 4 percent cement) aggregate bases were also studied. Performance of the bases was evaluated by plate bearing and Benkelman beam tests, roughometer tests, crack surveys, and maintenance required. The authors concluded that: (1) cement-treated poor quality aggregate produces an adequate base course; (2) cement modified bases containing more than 4 percent cement, but not enough cement to pass the freeze-thaw test, performed as well as soil-cement bases and were less expensive; (3) soil-cement mixtures should be compacted immediately after mixing; (4) asphalt emulsion produced no appreciable benefits; and (5) lime, at the rate of 3 percent, produced significant benefits when used in a ten inch base. (BPR Abstract)