Comparison of Geometric Characteristics of South Zagros Forest Road with Standard Construction Values (Case Study: Tang Sulak, Bahmiy)

The purpose of this study is to compare road geometry with standard road construction values. The studied area is Tang-e-Sulak, located in the city of Bahmiy (Kohgiluyeh and Boyerahmad Prov.), a protected area with its tourist, recreational and natural attractions in the southern Zagros forests. In this research, the existing road position was first taken using GPS and then placed on a topographic map. In the next step, the slopes were graded (from 0 to 10, 10 to 20, 20 to 30, 30 to 40, 40 to 50, 50 to 60 and more than 60 percent), then 11 samples were randomly selected on each slope. In the next step, the size of the taken samples was compared with the standard values (Booklet No. 131 and 161). The width of the running surface and right of way were analyzed on the basis of analytical statistics and other road geometric characteristics based on descriptive statistics. Soil samples were taken from each of the slopes of the slopes, and a soil sample was selected randomly for soil texture detection. Data analysis was done by T-test, Pearson correlation and SPSS software. The results showed that the width of the rudder and the constructional area of the road on the slopes (10-20, 40-50, 60-50, and 60) were less than the standard values and in the 1