Study On Seepage Characteristics Of Earth-rock Dam Based On Cloud Theory

China is a big dam-building country in the world,ranking first in both number and scale.Among the 98,000 dams built,more than 90% are earth-rock dams.According to statistics,the proportion of earth-rock dams in dam accidents is as high as 70.5%,most of which are caused by seepage failure.Therefore,it is not only of great practical value for the safe operation of the existing reservoirs,but also of great guiding significance for improving the dam construction level of earth-rock dams to identify the seepage damage of earth-rock dams in time,find the possible abnormal situations,and take measures to prevent accidents.However,there are still some problems in the theoretical calculation and analysis of earth-rock dams,such as the uncertainty of materials,loads,geometric dimensions and boundary conditions,etc.Therefore,it is urgent to study the distribution of seepage characteristics of earth-rock dams for seepage damage research.Therefore,cloud theory based on qualitative and quantitative transformation models has unique advantages in dealing with these fuzziness and randomness problems.The specific research contents and conclusions are as follows:(1)The sampling quantity and sampling method are analyzed,and the random sampling grid sampling method is adopted in combination with the actual topography of the borrow area.Carry out indoor particle size test and permeability test on the soil sample to obtain the particle size range of the soil;Coefficient of curvature is mostly distributed in the range of 1 ~ 3,indicating that the soil gradation in the borrow area is good,which can basically eliminate the influence of soil gradation and non-uniformity on permeability test.(2)After the infiltration test,the distribution test was carried out on the infiltration data.P-p diagram,histogram and non-parameter k-s test were used to prove that the permeability coefficient obeys logarithmic normal distribution instead of normal distribution.Combined with the knowledge of cloud theory,the characteristic values of clouds are obtained by using the uncertain reverse cloud algorithm,and the cloud diagram is drawn.It is proved that the permeability coefficient obeying the pan-normal cloud distribution.(3)According to the actual pipe-test data of luhun reservoir from 1979 to 1999,the expected Ex was obtained by reverse cloud computing.Entropy En and superentropy He compare the cloud digital characteristic values of the piezometer tubes in each section,and then analyze the operation state of the reservoir dam.Obey the normal distribution of cloud,the coefficient of permeability of known by finite element to calculate the corresponding pore water pressure,through the cloud reasoning model and the mapping relationship,the coefficient of permeability of piezometric level and the anti-seepage body of cloud reasoning simulation non-linear relation between the coefficient of permeability,based on the permeability coefficient of cloud reasoning uncertainty analysis method.This topic by the national natural fund "inversion of earth dam seepage and damage identification research on uncertainty theory and method of major national research and development program(51509091),much starker choices-and graver consequences-in the expansive soil bank slope and landslide dam seepage slide catastrophe mechanism yfc1501201(2017),much starker choices-and graver consequences-in national major research and development program of the cement particle material dam physical and numerical model and the characteristic evolution law"(2018 yfc0406803)funded project、Supported by the henan university science and technology innovation team support program(19IRTSTHN030)and other projects.