Durability of concrete with Belite-Gehlenite clinker as fine aggregate

The Japanese cement industry uses large quantities of industrial waste and by-products as raw materials in the production of cement clinker. Although the amount of industrial waste generated annually has remained almost constant, domestic demand for cement has been falling. In order to maintain the amount of waste re-used by the cement industry, there is a need to explore new ways of utilizing clinker besides in cement production. The proportion of waste used in the production of Belite-Gehlenite clinker featured in this study is about twice as much as in normal clinker. Previous studies have shown that when clinker is used as aggregate in mortar and concrete, clinker hydration products fill cracks as they occur for added self-healing performance. In this study, in addition to the basic characteristics of concrete containing Belite-Gehlenite clinker as fine aggregate, the resistance to cracking of specimens made with the concrete is investigated. Compared with concrete using natural sand, it is confirmed that compressive strength is improved, drying shrinkage is reduced, carbonation is suppressed, and freeze-thaw resistance is maintained. It is also demonstrated that resistance to cracking is improved.