Recent article in IJCSER
Investigation of Culvert Settlement in Hyrcanian Forest Roads
Author(s)- Mehran Nasiri
ABSTRACT
Forest engineers and hydrologists regularly calculate design culvert dimensions for use in wildland road-stream crossings. This paper describes a study undertaken to assess the effects of geometric design of forest road and culverts on the rate of culvert settlement of Hyrcanian forest. For this purpose, were measured geometric specification of culvert and proceeded to design cross section using ROADENG software. Results showed increased the rate of settlement with increasing culvert length. So that, was found significant difference among culvert settlements in classes of 0.5 to 0.9 meter and more than 0.9 meter. A significant inverse relationship, with equation of Y = -21.2ln(x) + 19.01 (R² = 0.64) was found between culvert depth and the rate of culvert settlement. The rate of settlement in uphill is more than downhill and the cut and fill slopes has no effect on the rate of settlement. Also, high cross slope of road has an important effect on the rate of culvert settlement. Increased the rate of settlement with increasing culvert skew as compared to 90 degree. So that, there was significant difference between the rate of culvert settlement in classes of 0 to 5 degree and other classes. Thus, inspections should focus on the structural integrity of the road prism, drainage systems, road surface, and sediment control.
