Seismic Liquefaction Analysis Of Slag-filled Concrete Dam Based On FLAC3

Earth and rock dams are very adaptable to the geology of the terrain and are the recommended type of dam in many complex situations.Where earth and rock dams are required,there is a shortage of natural clay and rockfill materials,but there is an abundance of weathered and slag materials,making slag panel dams the recommended type of dam.However,due to the complex geological conditions and the high seismic design intensity,the dam may be damaged by liquefaction during earthquakes,causing cracks,collapse or even dam failure,which may seriously affect the safety of the dam.Therefore,it is of great engineering importance and practical value to conduct an in-depth study on the liquefaction of slag panel dams,to analyse and determine their liquefaction potential under seismic conditions and to take anti-liquefaction measures to enhance the safety of dams.Using FLAC3 D software that uses the finite difference principle to calculate the possibility of liquefaction of a slagfill panel dam during an earthquake in operation,to study the effects of different key parameters on the degree and extent of liquefaction of the dam,and to investigate the preventive and control measures for liquefaction of slagfill panel dams:(1)A model of a slagfill panel dam was established,and the stress-deformation and seepage calculations were analysed in turn,and the results obtained were in accordance with the general rule.Next,the original seismic waves were filtered and baseline corrected using Seismo Soft,and the adjusted seismic waves were applied to the bottom of the model.A command flow was written in the fish language of FLAC3 D to visualise the liquefaction of the dam body.The superporous pressure ratio was defined and 15 typical monitoring points were set up to monitor the effective stress,super-static pore water pressure and superporous pressure ratio of the unit body for a more convenient and direct monitoring of the liquefaction of the dam body.The results show that under the seismic action,the pore water pressure of the slag pile increases,the effective stress decreases continuously,the superporous pressure ratio increases,and there is a possibility of liquefaction in the local area of the soil body.(2)Study the effect of porosity on liquefaction of slag heap panel dams.When the porosity decreases within a certain range,the drainage rate of the slag pile decreases,the pore water pressure dissipation becomes more difficult,the effective stress decreases,the superporous pressure ratio increases,the number of liquefied units in the dam body increases,the possibility of liquefaction becomes larger and more extensive,which is more unfavourable to the safety of the dam body.(3)Study the effect of permeability coefficient on liquefaction in slagfill panel dams.When the permeability coefficient decreases within a certain range,the infiltration line in the dam body is higher,more units are in a saturated state,the superporous pressure ratio of the units in the dam body is higher,and there is a greater possibility of liquefaction over a wide area,which seriously affects the safety of the dam.(4)In order to control seepage,reduce the infiltration line of the dam body and enhance the liquefaction resistance of the slag panel dam,an inclined L-shaped drainage body was arranged in the dam and the effect of the inclined L-shaped drainage body on reducing the liquefaction potential of the dam body was investigated.The results show that after the placement of the drainage body,the reservoir water can be quickly discharged from the dam,most of the cells in the dam are in a non-saturated state,the number of cells with higher superporous pressure is significantly reduced,and the liquefaction range is significantly reduced.The inclined L-shaped drainage body can effectively reduce the possibility of liquefaction of the dam.(5)Under the premise of good control of the seepage coefficient of the slag pile and good drainage,the safety performance of the slag pile panel dam against liquefaction can be ensured.In the selection of slag material as dam construction material,attention should be paid to the liquefaction problem of the dam body.On the basis of ensuring the stress deformation and infiltration safety of the dam body,the drainage performance of the dam material should be improved as much as possible to make the pore water pressure dissipate quickly.At the same time,it is recommended that drainage measures such as inclined Lshaped drainage bodies be used in conjunction with actual projects to improve the dam’s resistance to liquefaction damage.