The effects of using pulverized fuel ash as partial substitute for cement in concrete

Concrete blocks with different amounts of pulverized fuel ash (PFA) substituted for cement were manufactured and tested for their compressive strength, radium contents and radon exhalation rates. It was found that PFA increased the radium contents of the concrete blocks. However, the incorporation of PFA improved the compressive strength of the concrete blocks and decreased the radon exhalation rate. The recommended optimal percent of PFA to be substituted for cement is 15%, judging by the resulted compressive strength, radium content and radon exhalation rate.