The relation among physical and mechanical properties of rock and rock type is one of the most important interests for civil engineers and applied geologists because it is strongly associated with many geological problems at construction sites of tunnel, dam and etc.

The authors examined the relation between physical and mechanical properties (unconfined compressive strength and water absorption) of various rock types which was measured at construction sites by the Hokkaido Regional Development Bureau. As a result, it was found that data distribution of unconfined compression strength and water absorption of rocks fundamentally varies with the overburden pressure when rock was formed. When value of unconfined compression strength is the same, the value of water absorption of rock formed under high, medium and low overburden pressure is small, medium, and large, respectively. Here, rock which is thought to be formed under high overburden pressure is plutonic rock, metamorphic rock and sedimentary rock in an accretionary zone. Rock which is thought to be formed under medium overburden pressure is Mesozoic to Paleogene sedimentary rock of Yubari, Otoineppu and Ashibetsu area, Neogene sedimentary rock of Atsuma area. Rock which is thought to be formed under low overburden pressure is volcanic rock, Mesozoic to Paleogene sedimentary rock of Akan and Shiranuka area, Neogene sedimentary rock of Yakumo area, and Neogene pyroclastic rock.

From the comparison between sandstone and slate in an accretionary zone in Erimo area of south-central Hokkaido, we inferred that the difference of original material affects data distribution of unconfined compressive strength and water absorption.

This content is only available via PDF.
You can access this article if you purchase or spend a download.