The point load testing is widely used to determine rock strength indeces in geotechnical
practices as a result to simplicity. The present study presents correlation equations between
the unconfined compressive strength (qu) and point load strength index Is(50) adopted for
different types of rocks. In order to estimate a new correlation between the unconfined
compressive strength and point load strength test, more than 166 tests were performed. The
tests were conducted on four rock types including Sandstone, Siltstone, Limestone and Basalt.
The soil samples were collected from different sites along the new administrative capital of
egypt. The study shows a reliable correlation between the unconfined compressive strength
estimated from the two test approaches.