| The purpose of this research experiment was to find a possible use for recycled tires, by examining the reinforcement effects of sand, mixed with variously sized pieces of shredded tires. The shredded tires were supplied by Davis Rubber Company, of Little Rock, Arkansas. Davis Rubber Company has vast experience in shredding tires, as it was founded in 1924, and grinds waste tires and rubber for various uses, such as playground material, rubber mulch, and other similar uses.; The Standard ASTM Compaction (Method B, D698) and Bearing Ratio Tests (ASTIM D1883-87, California Bearing Ratio) were performed on #20 sand, mixed with 1/2" and 1" rubber tire shreds. Four different shred percentages were used, including a zero percentage, so that there would be unreinforced samples, to test against. Additionally, three different loading scenarios were considered, as well as four different moisture contents scenarios. This yielded a total of 60 tests.; The testing program yielded that mix sample 16C attained the highest CBR value at 0.2 inches of penetration of all the samples tested. The CBR value attained is 34.9%, making it a suitable mix for use as a Base or Sub-Base in a flexible pavement design. This mix had the most positive effects on the CBR of the sample (23.4% unreinforced to 34.9% reinforced) for a 40 lb surcharge sample. |
