| To address the ever increasing quantity of scrap tires produced in the U.S. a study is conducted on the use of crumb rubber in concrete for enhancement of structures against blast effects. Crumb Rubber Concrete (CRC) is produced by replacing a volume percentage of the traditional coarse and/or fine aggregate with crumb rubber particles. Crumb rubber is produced in various gradations from used vehicle tires. Part 1 of the research program characterizes the mechanical properties of CRC and provides an assessment of the capability of CRC in providing flexural resistance against blast effects. Part 2 of the research study examines the use of CRC for the specialized application of blast and ballistic protection. The program characterizes resistance of CRC to contact and near contact high explosive detonations, and examines depth of penetration, and perforation using V50 methods.;The results of part 1 of the experimental and analytical investigation found that (1) crumb rubber replacement of coarse and fine aggregate is done at a cost premium of approximately ¾ times the replacement percentage, (2) the addition of crumb rubber results in a decrease in unit weight, compression strength, splitting tensile strength, and elastic modulus, linearly related to the addition of rubber, (3) the modulus of rupture was not sensitive to up to 40% rubber aggregate replacement, and (4) flexural failure modes occur at lower demand levels for due to the use of rubber replacement. The reductions are in line with the material property conclusions previously discussed. |
