چكيده لاتين
The Tehran-North Freeway project is under construction and operation to provide a safer and shorter route between Tehran and the north of the country. According to the plans, this route is being built in four sections, of which three sections have currently been completed and opened to traffic, leaving only Section 3. Section 3 of the Tehran-North Freeway (as the last remaining section out of the (4) is considered a bottleneck in the country’s road engineering projects due to the geological complexities of the route. In this research, using spatial analysis and multi-criteria decision-making methods in a Geographic Information System (GIS), four proposed options for the route alignment were evaluated and compared. The criteria used included rock mass quality (covering rock type, rock strength, layer thickness, rock block size, joint spacing, RQD, weathering, and permeability), distance from fault zones, distance from rivers, distance from landslide zones, and the topographic conditions of the area, each playing a significant role in the stability and safety of the route. In the first stage, each criterion was individually weighted and scored within the GIS environment, and the corresponding maps were generated. Then, by integrating the information layers and applying the final weights, the final scoring map was extracted, and the overall score of the engineering geological characteristics for each variant was calculated. The results of the analyses showed that Variant No. 3 received the highest final score compared to the other variants, and it has the highest score in terms of engineering geological conditions such as rock mass quality, slope aspect, and route length compared to the other options. For this reason, from an engineering geological perspective, it is considered the most suitable option for the freeway alignment in the study area. The results of this research can be used as an effective tool in mitigating geological hazards and optimizing route selection in similar civil projects.
