عنوان مقاله [English]
The protection of agricultural lands from sea water intrusion in countries with low coasts is of great importance. The present study investigated a soil failure mechanism to measure seepage force by numerical simulation of a laboratory coastal dike in FLAC software using the finite difference method. The results indicate that the FLAC model properly simulated soil behavior. The model predicted boiling with high accuracy and it was possible to predict the heaving mechanism after use of blanket and sheet piles seepage control measures using the stress analysis before implementing the final design. The results show that it is possible to decrease the hydraulic gradient and, thus, risk of boiling by lengthening the flow path. The safety factor was determined using FLAC without the need for manual calculation. Terzaghi equations indicate that the safety factor against boiling depends on several geotechnical parameters. The safety factor was determined in FLAC by considering the geotechnical parameters of friction angle, angle of dilation, type of material, and angle of friction between the soil and sheet pile.
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