高温大理岩的动态能量耗散机理及破坏特征

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Study on dynamic energy dissipation mechanism and damage characteristics of high-temperature marble

Abstract：To investigate theefectofhightemperature ontheenergycharacteristicsofmarble，ANSYS/LS-DYNA was used tocaryout dynamiccompresionsimulation testsonmarble withsix temperature gradientsat five impact velocities toanalyze the mechanical propertiesof marbleunder high-temperature dynamic loading and the temperature efecton energyevolution， andto explore the energy criterion for strength failureof high-temperature marble from the perspective ofenergy dissipation. Theresults show thatthe Holmquist-Johnson-Cook （HJC）constitutivemodelcanreasonablyandefectively simulate the dynamic damage processof marbleunder diferent temperatures.With the increase in temperature，thedynamic peak strength anddynamicelasticmodulusof marbleexhibit aquadratic negativecorrelation with temperature，the dynamic peak strain exhibits a quadratic positivecorrelation with temperature，and the damage morphology is changed from X-type toconjugate shear damage.The increase in temperature reduces the energy storage capacity of the marble specimen to a certain extent， while heeffectofhigh temperature on theenergy dissipation capacityof marble is transformed fromafaciliting eect toan inhibiting effect with 600∘C as the cut-off point. When the temperature reaches 600∘C ，thepeak strength issignificantly reduced，the ductilityofthemarbleincreases，crushing damageispresented，andthedissipatedstrainenergyreachesthe maximum value. 600∘C can be used as the threshold temperature for the britte-delayed transformation of the marble.Based on thecharacteristicsofteenergy evolution process，thepointofasteep increaseindisipated strainenergyisregarded asa precursor information point of the precursor of overall instability and damage of marble.The inflection point at which the growth rateof theelastic energyconsumptionratio first appears isdefinedaccording tothecurveof thestress-elastic energy consumption ratio-strain relationship as the energy criterion of the strength failure of marble.

Keywords：high temperature marble; SHPB; energy dissipation; failure criterion

在向多元化“新能源时代”转型的大趋势下，为实现绿色低碳可持续发展，涌现出大量高温工程，如矿产资源开发[1]、地热开发[2-3]、核废料处置、高地温隧道施工[4]等，促使高温岩石力学和岩石损伤破坏等课题得到更多关注。（剩余17344字）