『Abstract
　The Alvand batholith is one of the largest plutonic bodies in the west of Iran. In this research, several physico-mechanical tests have been performed on granodiorite and porphiroid monzogranite consisting of five degrees of weathering in Hamedan area, west of Iran. Furthermore, weathering process of Alvand granitoid is studied by chemical analysis and petrographical studies. The results indicated that engineering properties of weathered granodiorite and monzogranite vary over the wide range depending on the degree of weathering. On the other hand, this research is focused on the assessment of relationship between weathering indices and uniaxial compressive strength. For this reason, some of the most important weathering indices are reviewed. It should be noted that, application of these chemical, engineering and petrographical indices are good quantitative indicators for describing the degree of weathering. Using these indices for the assessment of uniaxial compressive strength of granodiorite and monzogranite rocks, yields suitable and meaningful results.

Keywords: Weathering indices; Granodiorite; Monzogranite; Alvand granitoid』

Introduction
Geological setting
A review of the weathering indices
　Petrographical indices
　Engineering indices
　Chemical indices
Materials and methods
　Material identification
　Sampling and laboratory studies
Results and discussion
　Mineralogical characteristics
　Chemical analysis
　Physical and mechanical properties
　Weathering indices
　Correlation between UCS and weathering indices
Conclusions
Acknowledgments
References