Effect of the road technical and drainage properties on roadside landslides in watershed 85 in Golestan province

Identifying the effectiveness of different technical specifications and road drainage conditions is a scientific method for imaging areas where there is a risk of landslides. Landslides Damage and problems such as increased road construction costs, increased maintenance costs, Disrupts transportation and increases damage to cars. Therefore, due to the destructive consequences those roadside landslides on the possibility of access to the area and road maintenance costs to the authorities, it is necessary to identify the main causes of landslides and adopt appropriate executive strategies to control them. Be. The purpose of this study was to investigate the effect of technical characteristics and drainage of roads on landslides, roadside in the forest area of 85 Golestan provinces.

In the present study, first, all forest roads in the area were surveyed and all landslides with different areas were recorded by the Global Positioning System (GPS). Then, the technical characteristics of the road including longitudinal slope, height and slope of the trench, traffic volume, width and depth of the side atmosphere, distance from transverse slopes and diameter of slopes up to 100 meters on both sides of each slip point were measured. The correlation between technical factors and road drainage with the frequency and extent of landslides was determined by statistical analysis.

A total of 121 landslides were recorded in the watershed of 85 Golestan provinces, of which 22 on high-standard roads, 30 on medium-standard roads and 69 on low-standard roads was observed. On average, each landslide point on high, medium and low standard roads was 13.95, 43.17 and 60.14 square meters, respectively, and the total area of ​​landslides at these standard levels was 307, respectively. , 1295 and 4150 square meters.

The results showed that the frequency and area of ​​landslides had a positive and significant correlation with trench diameter, slope and trench height. This means that with increasing slope and height of the trench, the number and extent of landslides increased. Also, in places where transverse ridges were larger in diameter due to water flow, the number and extent of landslides were higher. The maximum diameter of the transverse ridges was 120 cm, but due to the high flow rate and soil moisture, these ridges could not prevent landslides. Therefore, it is recommended to use bridges and protective walls in such areas.