Where can I get information about making exposed aggregate surfaces by flame blasting?
This process was reported in Cement, (published in Amsterdam) No. 6, 1975, pages 259-261. The author, W. J. E. Louwerens, reports applying a temperature of 5,430 degrees F to the outer skin with a torch. As the surface is seared the hydrated cement and sand are pulverized and brushed off to expose the coarse aggregate. The author reports that the brief exposure to high temperature does not influence the critical properties of the main body of the concrete and that an attractive surface can be produced economically.