Study On Liquefaction Characteristics Of Graphite Tailings In Jixi Cit

Tailings dam is a high potential energy hazard,which is prone to liquefaction damage under the action of earthquake,and the damage is particularly serious.As the province with the highest graphite reserves in Asia,Heilongjiang Province should pay special attention to the liquefaction characteristics of graphite tailings dams.Currently,scholars still need to deepen their research on the liquefaction characteristics of graphite tailings dams.This article uses GDS dynamic triaxial test to conduct liquefaction tests on graphite tailings in Jixi City,Heilongjiang Province.The effects of consolidation ratio,cyclic stress ratio,freeze-thaw cycle,fine particle content,confining pressure,and saturation on liquefaction characteristics are studied.Based on the model formula proposed by Ishibashi,a pore pressure increment model sui Table for graphite tailings is fitted.The main tasks are as follows:Determine the natural moisture content,grading,optimal moisture content,and maximum dry density of graphite tailings through moisture content tests,screening tests,and compaction tests.Study the influence of consolidation ratio on the liquefaction characteristics of graphite tailings under three different cyclic stress ratios.Provide a time history curve,stress-strain hysteresis curve,residual strain relationship curve,and pore pressure relationship curve.Establish a common formula for liquefaction frequency to consolidation ratio and liquefaction frequency to cyclic stress ratio.The results show that an increase in consolidation ratio inhibits liquefaction,while an increase in cyclic stress ratio promotes liquefaction.Study the effect of freeze-thaw cycles on liquefaction characteristics,provide a time history curve,residual strain relationship curve,and pore pressure growth curve,establish a fitting formula between liquefaction vibration frequency and freeze-thaw cycles,and the results show that as the number of freeze-thaw cycles increases,the anti liquefaction ability first increases and then decreases,and the anti liquefaction ability is strongest in one freeze-thaw cycle.Study the influence of fine particle content,confining pressure,and saturation on liquefaction characteristics,and provide the relationship curve between strain,pore pressure,and liquefaction vibration frequency.The results show that the increase of fine particle content and confining pressure inhibits liquefaction,while the increase of saturation promotes liquefaction.The Ishibashi pore pressure increment model was applied to fit the pore pressure development of graphite tailings under different influencing factors such as consolidation ratio,freeze-thaw cycle,fine particle content,confining pressure,and saturation.The actual pore pressure development curve was compared with the predicted pore pressure development curve.The results showed that the Ishibashi pore pressure increment model can effectively simulate the pore pressure development during the liquefaction process of graphite tailings.