Binaloud mountain range is located in western to southern parts of Mashhad city. This mountain range is mainly composed of metamorphic rocks, ophiolotic complexes and acidic igneous rocks. This paper investigates 3 areas in west to southwest parts of Mashhad city with different rock types. Area number 1 in the west of the city with acidic igneous rocks, area number 2 in southwest of the city with ultrabasic rocks and area number 3 in the west to southwest parts of the city with metamorphic rocks. After rocks study and quality assessment, drillability of the study area was investigated and then rock support system for all three areas was recommended based on RMi classification system. The results show that areas with acidic igneous rocks such as area 1, due to the presence of minerals resistant to weathering, rocks show high quality (RQD) and the drilling type and support system have no significant difference. In contrast, in areas with ultrabasic rocks which have minerals with low weathering resistance such as area 2, rock quality decreases and drilling type as well as support system might be highly variable even in a small area. In rocks with high degrees of weathering such as those found in area 3, due to clay and iron oxide formation, rocks have lost their structure, rock quality is very poor and rock support systems are not usable.

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