Simulation And Analysis Of Seepage Stability Of Dike In Cold Area Under Variable Water Level

Embankment engineering is an important protective barrier for the flood control.Especially in cold regions,the phenomenon of thermal expansion and contraction will occur,which will cause surface cracks of levee and internal seepage channels.When the upstream water level changes,seepage and piping will easily occur.Therefore,in order to study the embankment in the cold environment,the water levels of the representative such as the spring flood and the summer flood in the selected area are fully validated for the safety of the embankment.The characteristic of the water level includes the water level of the normal in spring,the flood level of the designed,the water level of the highest in summer,the once-in-a-century flood level and the highest flood level in spring.The seep module in Geostudio is used to simulate seepage and analyze slope stability.The results are as follows:(1)the pressure line,the seepage path,the seepage rate,the seepage gradient and the minimum safety factor have changed correspondingly under the influence of ice flood.(2)Under the same water level,compared with non-ice flood season,the maximum velocity of dikes in season of the ice flood varies greatly,which is 5 times,23 times,9 times,9 times and 8 times of non-ice flood season.The maximum velocity basically occurs at the foot of the downstream dike.(3)Under the same water level,the seepage gradient in the season of ice flood is larger than that in non-ice flood season.The maximum water level gradient is 1.84,and the approaching gradient is 2,which is very close to the critical gradient.(4)With the increase of water level and water pressure,the minimum safety factor of embankment decreases continuously,which is 5.222,5.033,4.968,4.901 and 4.718,respectively.It is much larger than the engineering allowable critical safety factor.