Concrete Tensile Strength Specimen Size Effects

Three concrete mixtures with different nominal maximum size aggregates (NMSA) were developed and 3-foot cubical blocks were cast from which cores of various diameter were extracted for testing. Specimens were cut from the cores and tested in compression, splitting tension, static direct tension, and cyclic dynamic direct tension. Due to the complexity and cost associated with obtaining and testing the specimens, only a very limited number of tests were conducted. The research project was not intended to present a statistically representative sample size, but to see if any trends could be observed for each combination of NMSA and core diameter. The Principle Investigator for the project left Reclamation prior to completing a draft report. Subsequently, staff from the Concrete, Geotechnical and Structural Laboratory assembled the figures and data to present in this report. By documenting this program and the test results, future studies can be performed that will add to the available data and perhaps lead to more robust findings.