3 Dimensional Random Seepage Field Theory and Researching for Levee Construction

Since the complicacy of practical seepage problem effected by various random factors, the three dimensional simulation and analysis for stochastic seepage field has an important meaning in engineering applications. The three-dimensional anisotropic heterogeneous steady random seepage model and designed program are developed on the basis of Finite Element Method. A statistical analysis of stratum soil characteristics and geological columns sampled from the main embankment of Yangtze Rive in southern Jingzhou zone of China is carried based on practieal engineering projects. The statistical hypothesis of Gaussian probability distribution for random permeability tensors of soils to be submitted into the stochastic seepage field simulation was verified that this assumption would be accepted by the statistical testing based on Kolomogorov-Smirnov theory. Various statistical characteristics and random natures in random seepage fields of the main embankment of Yangtze Rive in southern Jingzhou zone of China were investigated by numerical analysis for stochastic seepage fields simulations using three dimensional Finite Element Method as well as the rationality of simulated stochastic results and the developed model were also examined through statistical testing. Especially, the random variation of upstream and downstream water level as a stochastic boundary condition was taken into account of three-dimensional finite element model in practical analysis for the random seepage field simulations in order to describe disturbed effects of the boundary randomness due to variability of downstream and upstream water level over variabilities of simulated results presented by vector series of the random seepage field. Furthermore, the function of some safeguards to set up against the seepage problem, such as sheet-pile breakwater and eatch-water,as the turbulence of complex boundary condition together with the effects of variability of soil permeability have been analyzed for description of influence of them on the hydraulic potential distributed in the random seepage field and compared with the result obtained by determinate analysis for the corresponding steady seepage field problem.That presents the necessity,feasibility and practicability of employing stochastic studies in seepage field problems.The developed method provides a more detail and full stochastic algorithm to characterize and analysis for three dimensional random seepage field problems.The conclusion of simulated analysis is reliable in comparison with pertained stochastic checking and measured data from practical engineering.