The objective of this study was to determine the tensile strength, cyclical behavior, and stress-strain relationships for concrete under loading conditions ( 1 to 10 Hz) such as could be produced by an earthquake.

Dynamic direct tension tests and stress-reversal tests were conducted on core specimens from two concrete mixtures representative of mass concrete. Test procedures were developed for cyclical loading and loading to failure in 0.25 to 0.025 s, which represent one fourth of a cycle having a frequency of 1 to 10 Hz. Stress-strain measurements were made on selected specimens. The procedures used could be modified to become ASTM test methods for direct-tension and stress-reversal tests of rock.

The tests indicated that there was no significant difference in tensile strength determined statically or dynamically on dry specimens. A 30 percent increase in strength was indicated for wet specimens tested dynamically. Very little hysteresis was evident in the tensile stress-strain curves. The results should be useful in studies conducted to determine the earthquake resistance of mass-concrete structures.