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I I I I I I I I I I I I I I I I I I I Transport Tire, Inc. -13- Harch I; 1983 or technician. Areas which deflect or rut in excess of 2 inches or are unstable should be compacted in place if the loose soils are suitable and at the proper moisture content for compaction. Unsuitable soils should be removed and replaced with a select compacted granular fill as previously discussed. For silty sand subgrade soils, we recommend that the pavement design be based on a California Bearing Ratio (CBR) value of 10 or a Hveem stabilometer (R) value of 40. For light or moderate street traffic with light truck traffic, pavement sections consisting of 1-1/2 inches of asphaltic wearing course, Minnesota Deparbnent of Transportation (MNDOT) Class 2341; 1-1/2 inches of asphaltic binder course, MNDOT Class 2331 compacted to 95% of the maximum Marshall laboratory asphalt compaction test ASTH D-1559; and 6 inches of a well graded, relatively free draining crushed aggregate base course (such as MNDOT Class 5 or Class 6) should be adequate. The asphaltic surface course mixtures should have a minimum stability of 1,200, a void content of the compacted mixutre between 2% and 6% and a flow value of not more than 18. The crushed aggregate base course should be compacted to at least 95% of the maximum dry density obtained in accordance with the Modified Proctor Method. Silty and clayey sands are susceptible to frost action and loss of strength during freeze/thaw conditions. Even after compaction and fine grading, silty subgrades can lose strength when allowed to become saturated or subjected to freeze/thaw conditions. Infiltration of water into the subgrade should be minimized by providing adequate drainage of the pavement STS Consultants, Ltd.