Specifying the soil types and profiling the subsurface soil layers are the excellent examples of CPTu test potentials. In this research, the capability of CPTu test for specifying subsurface soil layers and classification of the sediments in Urmia Lake is investigated. According to previous studies, the sediments of Urmia Lake are commonly fine grained and soft deposits with organic materials. To evaluate the geotechnical parameters of these sediments in Urmia Lake Bridge site, CPTu test was performed and soils were classified applying the results of this test. The results showed that the sediments are mostly composed of clay and silt. To verify the results of CPTu tests for soil classification, the outcomes were compared with the logs of the boreholes and the results of laboratory tests. Comparisons and analysis of findings showed high consistency between the three groups of results; CPTu, boreholes logs, and laboratory tests. Thus, CPTu test can be used, with sufficient confidence and accuracy, to specify and classify the soft soil in lacustrine environments. Manuscript profile

The load entering from the ground surrounding on the tunnel’s lining is one of the effective parameters in the designation of a tunnel. The amount of this parameter, which is called Rock load in a rocky environment, depends on several factors such as the overburden thickness, geological and geomechanical conditions and the depth of tunnel. In the present study, the amount of rock load for the Lot 2 of Imamzadeh Hashem Tunnel (L2IHT) has been evaluated using various methods and the effect of geological characteristics of the rock units on the tunnel route has been investigated. For this purpose, different methods for estimating the rock load were introduced firstly, and then the amount of this parameter for the tunnel was estimated using these methods. To evaluate the thickness of the plastic zone around the tunnel, the numerical method, finite difference code of FLAC3D software, has been used. Comparison of the results obtained from different methods and their analysis indicates that the rock load applying from H-4 and H-10 rock units is more than the other units. This happens because of the specific geological characteristics of these rock units such as high degree of crushing due to the geological factors and being in the faulted zone. Therefore, it is required for the stronger lining of the tunnel in the range of these units. Manuscript profile