Computation Of Earth Pressure In Complicated Condition Basing On Critical Slip Field Theory

The critical slip field theory of slope had been widely applied to solve slopestability, earth pressure and bearing capacity, which would be further promoted in thispaper to solve the earth pressure calculation problem on both sides of the retainingwall under seepage condition caused by water levels amplitude. Based on the projectbackground by analysis retaining and calculation of earth pressure on the retainingwall, considered the real boundary condition of seepage field, a new method incalculating earth pressure under complex conditions will be introduced in this paperfocusing on calculating the earth pressure in seepage caused by water level differenceon both sides of retaining wall. The calculation principle and numerical simulationprocesses were elaborated, and the calculation program of the critical slip field whichbased on triangular slice was also scheduled.Due to the equal effect of split and combination calculation of water and earth,calculated the earth pressure in seepage by water earth combination calculation in thispaper. First, a model established to calculate water pressure in complex seepage withthe Seep/W software by analysis seepage finite element. Then apply the triangularslices method based critical slip field, put the water pressure value into force analysisof slices as load items to calculate the earth pressure under different water level onboth sides of retaining wall. The validity of the method proved by comparing with thecalculation examples, and analysis of seepage impact on the size of earth pressure isintroduced in this paper. Through the comparison, seepage obviously effect on earthpressure, the earth pressure increases on the higher water level side in the active field,while decreases on the lower water level side in passive field.Then, the earth pressure in the retaining wall when draining devices are arrangedto reduce different water level on both sides is analyzed in this paper. It is concludedthat the different water level difference on both sides of retaining wall is related to theeffect of seepage to earth pressure, by comparing the active and passive earth pressurevalue under different water level differences. If the water level difference decreases,the effect of seepage to earth pressure diminishes quickly, while the water leveldifference is less than1.5meter, the effect of seepage can be neglected; to the passivefield, when the water level difference decreases, the pressure to passive earth diminished obviously while the seepage effect slightly smaller.Finally, calculate earth pressure under the condition of seismic load with criticalslip field, and get the corresponding sliding surface, compared with the results whichcalculated by M-O method widely used in the engineering calculation。It shows that:the active earth pressure is increased by seismic force, while making the passive earthpressure decreased, this conclusion is just the same as M-O method, which fullyverified the practicability and reliability of the method in this paper.