- 309-A New Model for Evaluating the Geological Risk Based on Geomechanical Properties — Case Study : The Second Part of Emamzade Hashem Tunnel

Risk assessment of tunneling projects has been considered as one of the most notable topics in the geotechnical engineering. In this process, there is a significant collection of variables and uncertain data in identification and prediction of the project’s hazards. Hence, this study aims to develop a new model for evaluating the geological risk using meta-heuristic algorithm like imperialist competitive algorithm (ICA) based on stochastic optimization techniques and then compare the results obtained from modeling and other studies conducted. For this purpose, first, field and laboratory tests are conducted to measure four important geomechanical and physical parameters such as Rock Mass Rating (RMR), Barton Index (Q), Uniaxial Compressive Strength (UCS), Density and Average Groundwater Table which were utilized as the input parameters during 7 sections of the excavation route. These seven sections have been classified into two separate clusters and then a comparison was made between the results of optimization and other results. The present research was studied on the second part of Emamzade Hashem tunnel in the northeast of Tehran (Iran). The results obtained demonstrate that imperialist competitive algorithm can be applied as a powerful mathematical tool and a reliable system modeling technique to evaluate geological risk of tunneling projects.