不同状态下冰冲击的力学特性

打开文本图片集

中图分类号：0383 国标学科代码：13035 文献标志码：A

Experimental study on mechanical properties of ice shock under different states

XIEBeijing， CHENMingjin， CHENSiyu，LIUZhiyao （School of Emergency Management and Safety Engineering， China University of Mining and Technology-Beijing，Beijing10oo83， China）

Abstract：To investigate the dynamic mechanical characterization of non-pure and non-intact ice materials under impact loads，a modified split Hopkinson presure bar （SHPB）was used. Rapid loading，rod end cooling and waveform shaping techniques were usedtoensure thestabilityof the ice material and achieve dynamic stressbalance during loading.Theimpact mechanical properties of complete ice （pure water， containing 2.5% 3.5% 4.5% salt， containing 2.0% 4.5% 8.5% coconut） and spliced ice （splicing interface inclination 30∘ 60∘ ）at freezing temperature of -10°C were studied. The strain rate ranges from 150-250s-1 . The failure process was recorded by using the high-speed camera triggered simultaneously with the pressure rod.Thecoelationbetwee thestressandstrainofthe sample，along withthe failure process，was determined byanalyzing thetime history curve of sample.The failure mode ofthe spliced icesample was analyzed by combining the Mohr-Coulomb strength criterion.Theresultsshowthatthepure watericeexhibitsthehighestcompressivestrength，followedbytheicewith coconut shreds，andbothof them showapositivestrainrateeffect.However，thecompresive strengthoftheice with salt additiondecreases significantlydue toits loosestructureandthe strainrate efect is notobvious.The dynamiccompresive strengthoficesamplesadded withcoconut fiberincreases firstlyandthendecreaseswiththeincreaseofcoconut fibercontent. Icesamples withhighcoconut fibercontentare prone to“doublepeak"phenomenonduetothebinding efectofcoconut fiber on broken ice withsmallparticle size.The splicing plane affects the crack growth， resulting inlower compresive strength than the intact icesample，and affects the failure mode aswell.The ice with smallinterface inclination is mainlydamaged by interfaceslip，whiletheicewithlargeinterfaceinclinationismainlydamagedbywholeice，whichissimilartotheintactice. The research results provide theoretical basisand method reference for the dynamic mechanical properties of non-pure and non-intact ice materialsunder impact loads.

Keywords： ice; impact damage; split Hopkinson pressure bar; dynamic mechanical characterization; high-speed camera

冰在自然界中十分常见，它与众多的人类活动有紧密联系，例如：冰雹对房屋、汽车[2]、飞行器]等造成的损伤，南北极等寒冷地区中应用的破冰[4]技术等。（剩余15876字）