Effect of uncertainty of hydraulic conductivity and number of samples in Monte-Carlo method on time-dependent variation of soil consolidation

Document Type : Research Paper


1 Academic staff, Dept. Water Engineering, University of Guilan

2 B.Sc. Student of University of Guilan

3 B.Sc. student, University of Guilan


The uncertainty of hydraulic conductivity plays an important role in probabilistic analysis of consolidation of soils. In current research, a computer program was developed in MATLAB and solving the governing partial differential equation using numerical finite difference method, it was applied as the basis solution to Monte-Carlo simulation. Meanwhile, the effect of number of random samples was investigated applying 100 and 1000 samples from log-normal distribution of hydraulic conductivity (related to a land located in Saravan-Guilan) into the probabilistic consolidation model. The results showed that the probabilistic distribution curve of pore-water pressure becomes flatter with time and the uncertainty increases. Increasing the number of hydraulic conductivity samples from 100 to 1000 caused negligible effect on the probabilistic distribution of pore-water pressure. Moreover, the greatest goodness of fit of normal distribution to pore-water pressure obtained close to the soil surface and 23 percent greater than the center of soil layer.


Main Subjects

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