Abstract
We authors made a few types of artificial gravelly rock, which had relatively lower contrast in mechanical properties between gravel and matrix. similar to one of breccia-type andesite and tuff breccia from Neogene volcanic gravelly rocks in Hokuriku district. We used the unconfined compression test. and investigated the relationships between gravel content and mechanical properties of them. As the result of this investigation, for example. larger the gravel content, smaller the uni-axial strength, the failure strain and the limit strain. These are different from the result about the natural gravelly rocks mentioned above, which have no relationship between gravel content and mechanical properties of rocks for example uni-axial strength. It might suggest the necessity of investigation not only about gravel content but about another factors from the natural gravelly rocks.
