The point-load index is presented as a convenient alternate method for determining relative strength of concrete or as a method of estimating concrete compressive strength. The test method presently is accepted in rock mechanics but is relatively new to the field of concrete. The test is quick, inexpensive, reproducible, and the test equipment is portable. The test involves application of a load via two conical platens across the diametral or axial axis of cores or cylinders. It was concluded that there is a strong relationship of point-load index with compressive strength. At this time, each job-mix relationship should be determined individually for compressive strength estimations. Two methods of size correction are presented. For most purposes, initial specimen diameter should be used for calculating the point-load index, and the specimens should be loaded diametrally for testing cast cylinders and cores drilled parallel to concrete "bedding" planes.
- Compressive Strength,
- Concretes,
- Loads (Forces),
- Mechanical Tests,
- Tensile Strength,
- Tests,
- Materials Research
Available at: http://works.bepress.com/david_richardson/79/