The mixing time of wall clay is decided based on experience and intuition of plasterers. There is no clear description about the mixing time of wall clay. In this study, the load electric power of bi-axial forced mixer is measured to grasp the optimal mixing time of wall clay. The influence of mixing time on the mechanical characteristics of wall clay is examined based on the unconfined compression tests for every mixing time. As a result, the optimal mixing time of wall clay with much clay fraction is estimated to be about 50 minutes in the range of this study.
