Facilities built in areas affected by earthquake activity, such as tunnels, which have always been an integral part of human life, must withstAND both dynamic AND static loading. It has led to the need for practical studies on the effects of earthquakes on underground structures AND the factors affecting their destruction. For this purpose, in this research, at first different patterns of tunnel’s excavation were investigated AND by using Plaxis 2D software AND based on Tabas earthquake in Iran, sensitivity analysis on geotechnical parameters of the SOIL surrounding tunnel such as cohesion, friction angle, unit weight AND modulus of elasticity was carried out, AND the parameters whose changes have the greatest AND least effects on the bending moment changes on the tunnel lining are introduced. The results show that tunnel excavation patterns significantly affect the bending moment, axial forces, displacements, AND surface settlement of the tunnel. Often, by dividing tunnel excavation area to small parts, the values of bending moment, axial forces, displacements, AND surface settlement of the tunnel decreases in static analysis. Also, outputs of sensitivity analysis on geotechnical parameters of the SOIL surrounding tunnel showed that modulus of elasticity of the SOIL surrounding tunnel has the most effect AND cohesion changes have the least effect on bending moment induced on tunnel lining..

By development of ship dimensions AND the necessity of berthing of high tonnage ships, there was a need for an appropriate structure with optimum energy absorption behavior. Since the conventional berthing facilities (such as quays, sheet piles, etc.) could not experience large displacements, absorbing a large amount of energy by them is satisfied by applying high forces. Besides, due to the high drought of big ships, providing the proper depth for berthing of these ships will cost a lot. All above discussions have led the designers to use an appropriate structure in deep water that in addition to absorbing energy through experiencing large displacement, the repairing cost of that be independent to the other facilities. The most appropriate structure fulfilling this purpose is the monopile. Because of high forces exerted on monopile, the large displacement will occur in the surrounding SOIL which makes the SOIL behavior nonlinear. In addition, presence of water around the structure AND also dynamic behavior of ship impact phenomenon makes the analysis complicated. In this paper in order to satisfy the above mentioned parameters, AND to consider the water-structure-SOIL interaction, Ansys7.0 is used AND based on the obtained results, the design curves have been extracted in such a way that the dimension of monopile could be obtained via them by having SOIL characteristics, water depth, ship tonnage AND its velocity as input.

Because of the development of wind turbine farms in seismic areas, such as East Asia, southern Europe, AND the United States, as well as the importance of the foundation of the wind turbines in the design AND implementation, it is necessary to study the seismic behavior of wind turbine foundations. In this study, the seismic behavior of monopile foundation of a simplified offshore wind turbine model under a specific earthquake record was evaluated by using finite element method in OpenSees software. At first, the proposed numerical model was validated by the results of a dynamic centrifuge modeling of a steel pile located in sANDy SOIL. Then, the effects of various parameters such as dimensions of monopile (diameter AND length), SOIL relative density, end bearing pile effect AND wind load effect were evaluated. The results of this study showed that the changes of these parameters have significant effects on the seismic behavior of the monopile of offshore wind turbines. Increasing dimensions of monopile (diameter AND length) AND SOIL relative density improves the seismic performance of the structure AND foundation system AND reduces lateral displacement at the top of tower AND reduces settlement AND rotation of the monopile. Chang of behavior of the monopile from frictional pile to end bearing pile, improves the behavior of the wind turbine structure AND foundation under seismic loading. Also, wind loading causes more displacement AND rotation to the structure, AND static wind load creates more critical conditions than the dynamic wind load.

In order to predict the behavior of SOIL-related phenomena, it is necessary to have knowledge about unsaturated flow AND using models that provide optimal estimates of the retention curve AND hydraulic conductivity of SOILs. Despite the widespread use of the classic van Genuchten-Mualem model (VGM), this model usually performs poorly in predicting hydraulic conductivity AND modification of some of its parameters seems necessary. In this research, 283 SOILs from different textures of the UNSODA bank were selected AND divided into two sections of calibration AND validation AND their SOIL parameters were exported AND categorized. Then, by defining the modified unsaturated hydraulic conductivity (Ksc) instead of the saturated hydraulic conductivity (Ks) AND determining the limits for l AND n parameters, the hydraulic conductivity-moisture function of VGM were solved using 24600 pairs of points li AND nj for each SOIL of the three main SOIL texture classes. In the following, the optimal l value (l̂) of each texture class was selected based on the minimum value of the hydraulic conductivity estimation error using the root mean square error (RMSE) index AND the n values that had created the minimum errors, were selected as the optimal pore size distribution coefficients of the hydraulic conductivity-moisture function (n̂opt). In order to create pedotransfer functions for estimating n̂opt, we ran stepwise regression in MATLAB software considering the condition of statistical significance (P-value=0.05) for independent variables AND functions for each SOIL texture class. After creating pedotransfer functions, the results of the proposed method of this research (MVGM) were compared with the VGM results using RMSE AND Nash-Sutcliffe (NSE) indices. The results showed that in both sections of creation AND validation functions, the MVGM performed better in estimating hydraulic conductivity AND had a higher efficiency index in all textural classes of SOIL.

Phytoremediation of lead using plants in lead-contaminated SOILs is a new AND safe environmental technology. By adding chelators AND increasing plant extraction, the efficiency of this technology can be increased. In this regard, we evaluated the effect of adding EDTA chelates to lead-contaminated SOILs to investigate the amount of lead accumulation in a medicinal plant, Calendula officinalis. We designed a factorial experiment in the form of a completely rANDomized, with three replicates in pots AND two factors including EDTA at two levels (0, 50 mg kg-1) AND lead at four levels (0, 30, 90, AND 270 mg kg-1). In this plant, the accumulation of lead was accompanied by an increase in the amount of lead in the SOIL due to the addition of EDTA to the SOIL. The results showed that EDTA significantly increased the lead translocation of lead from roots to the aerial part of the plant.Total Chl. AND shoot dry weight decrease significantly in EDTA treatment than control specific at a high level of Pb in the SOIL. Also, the results showed that EDTA increased lead removal from SOIL to SOIL solution AND increased lead translocation from roots to the aerial part of the plant of Calendula officinalis. In general, the results of this research showed that with the careful management AND EDTA use in lead extraction, it has provided a cost-effective AND safe environmentally strategy.