Abstract
Inrecentyears,theproblemofhighgroundtemperaturehasattractedmoreand
morescholarsattention.Someundergroundcavesandtunnelswithhighrock
temperaturewillcauseasuddendropinhightemperatureoftheliningconcreteduring
initialwaterflow,andthenformatemperaturegradientstate.Thetemperaturestress
causedbythishugetemperaturegradienthasagreatimpactonthemechanical
propertiesoftheconcreteliningstructure,whichhasacertaineffectonthestabilityof
theproject.Itisofgreatpracticalsignificancetostudythemechanicalbehaviorof
concretebodiesundertemperaturegradients.Acousticemissionisoneofthe
non-destructivetestingmethods.Theuseofittomonitorconcretedamageandstress
hasbeenrecognizedbymanyscholars.Acousticemissionparameterscanprovide
certaintheoreticalcriteriaforconcreteinstability.Basedonthisengineeringbackground,
inthispaper,themodeloftemperaturedropinconcreteunderdifferenthigh
temperatureconditionsisestablished.Thepapermainlystudiedtheheatconductionlaw,
mechanicalpropertychangesandfailuremodesofconcreteunderdifferenttemperature
gradientsaremainlystudied.Thenthebasicparametersofacousticemissionandthe
sizeofacousticemissiondamageareusedtoreflectthedegreeofconcretedamage.The
frequencyspectrumoftheconcreteunderthetemperaturegradientisanalyzed,which
providesatheoreticalbasisforthestabilityoftheconcreteunderthetemperature
gradientoftheactualproject.Themainresearchcontentsofthisarticleareasfollows: