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dc.contributor.advisorTeder, Marko
dc.contributor.authorHani, Mirko
dc.date.accessioned2014-06-05T05:46:20Z
dc.date.available2014-06-05T05:46:20Z
dc.date.issued2014
dc.identifier.urihttp://hdl.handle.net/10492/1714
dc.description.abstractKäesolevas magistritöös on võetud vaatluse alla puidu tugevusnäitajate uurimine mittepurustavate meetoditega ehk võrreldakse ultraheli ja heli mõõtmistulemusi puidu mehaaniliste näitajatega. Töö eesmärgiks oli leida, kui täpselt oleks võimalik määrata kasutusel mitte olnud kuuse- (Picea abies) ja männipuidu (Pinus sylvestris) tugevusparameetreid akustiliste mitte-purustavate meetoditega. Puidu füüsikalis-mehaanilised omadused määrati vastavalt standardile laboratoorselt. Ultraheli levimiskiiruse mõõtmised teostati katseseadmetega Ultrasonic Instrument TICO koos silindriliste 54 kHz otsikutega ja Proceq Pundit Lab koos kooniliste 54 kHz otsikutega. Heli levimise mõõtmised teostati Fakopp Microsecond Timer seadmega. Seadmetega teostati puitelementidel mõõtmised otstest pikikiudu, nooremate aastarõngaste poolt pikikiudu (otsikud ligikaudu 45º all) ning nooremate ja vanemate aastarõngaste poolt pikikiudu (otsikud ligikaudu 45º all). Erinevate mõõtmisviiside vahel esines nii kuuse- kui männipuidul enamasti keskmine või tugev korrelatsioon. Hindamaks puidu mehaanilisi omadusi, andis kuuse puhul paindeelastsusmooduliga tugevaid seoseid Fakopp Microsecond Timer´iga mõõdetud väärtused (r=0,78-0,86) ja Pundit Lab seadmega otstest pikikiudu mõõtmine (r=0,75). Männi puhul olid samuti Fakopp seadmega saadud väärtused tugevas seoses paindeelastsusmooduliga (r=0,75-0,8) ning lisaks sellele saavutas tugeva korrelatsiooni ka Ultrasonic Instrument Tico seadmega otstest pikikiudu mõõtmine (r=0,81). Individuaalsete argumentide regressioonanalüüside põhjal andsid Fakopp seadmega tehtud mõõtmised mõlema puuliigi puhul enamasti tugevaid seoseid elastsusmooduliga. Töös selgus, et puitkonstruktsioonide füüsikalis-mehaaniliste omaduste hindamiseks on võimalik kasutada ultraheliga ja heliga mõõtmisi. Saavutamaks veelgi stabiilsemaid ja paremaid mõõtmistulemusi, tuleks kindlasti jätkata täpsustavate lisauuringutega selles valdkonnas.est
dc.description.abstractThis master thesis takes under observation the investigation of wood strength properties with non-destructive methods like comparing ultrasound and sonic results relations with mechanical properties of wood. The purpose of this work is to find out how accurately can we determine never been used spruce (Picea abies) and pine (Pinus sylvestris) strength parameters using acoustic non-destructive methods. The physical-mechanical properties of wood were determined in laboratory conditions according to standard. Ultrasound velocity measurements were carried out using devices like Ultrasonic Instrument TICO with cylindrical 54 kHz transducers and Proceq Pundit Lab with conical 54 kHz transducers. Sonic measurements were carried out using the device called Fakopp Microsecond Timer. There were performed measurements from the elements ends longitudinal, from the younger annual rings side longitudinal (transducers approximately 45º) and from the younger and older annual rings side longitudinal (transducers approximately 45º). There occured mostly medium or strong correlation within different measurements in spruce and pine wood. To evaluate wood mechanical properties, the strongest correlations with modulus of elasticity in spruce were achieved using Fakopp Microsecond Timer (r=0,78-0,86) and Pundit Lab (r=0,75) device measurement from the elements ends longitudinal. In pine, the measured values from the Fakopp device were also in strong correlation with modulus of elasticity (r=0,75-0,8) and also the Tico device measurement from the elements ends longitudinal achieved strong correlation (r=0,81). Individual arguments used in regression analysis gave also strong correlations between the measurement results received from the Fakopp device in both species and modulus of elasticity. Work reveals, that it is possible to predict the physical-mechanical properties of wood structures using ultrasonic and sonic measurements. In order to achieve more stable and better measurement results, there should be done additional researches in this field.eng
dc.subjectmagistritöödest
dc.titleKuuse- (Picea abies) ja männipuidu (Pinus sylvestris) tugevusparameetrite uurimine akustiliste mitte-purustavate ja purustavate meetoditegaest
dc.title.alternativeInvestigation of strength properties of spruce (Picea abies) and pine (Pinus sylvestris) determined by acoustic non-destructive and destructive methodseng
dc.typeMaster Thesis
dc.date.defensed2014-06-09


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