Research scientist, Virginia Highway and Transportation Research Council, Charlottesville, VA
This study investigated the feasibility of using neoprene pads confined by steel end caps instead of sulfur-mortar caps in compressive strength tests on 150- by 300-mm (6- by 12-in.) concrete cylinders. The 13-mm (½-in.) thick neoprene pads had a 50 durometer hardness and were cut to fit in the end caps, which had an inside diameter of 159 mm (6¼ in.) with a tolerance of +0 and −2 mm (−1/16 in.). Compressive strength data were obtained from 438 pairs of cylinders prepared in the field from commercial batches of concrete. One cylinder of each pair was tested with neoprene pads and the other with sulfur-mortar caps. Although the results indicate statistically significant differences in the values obtained by the two capping methods, the differences are considered negligible from a practical standpoint. A linear regression analysis indicated a good correlation between the two methods.
Paper ID: CCA10040J