Massiivpuidust võrkkooriku modelleerimine ja selle käitumise uurimine koormamisel
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Kuupäev
2015
Kättesaadav alates
Autorid
Teder, Triina
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Puidust võrkkoorikutel on mitmeid eeliseid: nad on tugevad ja nendega saab katta suuri
sildeid ning nad loovad keskkonnas hea arhitektuurilise ilme. Kuigi puidust võrkkoorikutel
on mitmeid eeliseid, ei ole need veel väga levinud ning paljudes instituutides uuritakse
nendega seotud probleeme ja üritatakse nende projekteerimist lihtsustada. Antud töö
eesmärgiks on luua võrkkooriku katsekeha ning uurida selle käitumist ja sellega
seonduvaid probleeme koormamisel.
Kooriku arvutis modelleerimiseks kasutati arvutiprogrammi Rhinoceros 5, mille mudeli
järgi koorik valmis ehitati. Koorikut koormati sõlmedest riputatud kettidest moodustatud
kangsüsteemi kaudu. Kooriku käitumise uurimiseks mõõdeti sõlmede vertikaal- ja
horisontaalsuunalisi siirdeid elektrontahhümeetrit ja miniprismat kasutades. Selgus, et
selline meetod on lihtne viis uurimaks konstruktsiooni paigutisi.
Modelleeritud koorik käitus sarnaselt tüüpilisele koorikkonstruktsioonile. Enne kooriku
purunemist ilmnesid selles suured deformatsioonid ning purunemiskoht oli etteaimatav.
Koormuse eemaldamisel taastas konstruktsioon suures osas oma kuju. Peamised
probleemid ilmnesid seoses lattide kinnitamise tarbeks ehitatud puitraamiga, kus latid
paigaldati raami aukudesse. Mõjuva koormuse tagajärjel tekkisid raami aukudes
muljumised ning konstruktsioon deformeerus ebasümmeetrilist. Sellegipoolest on töös
esitatud meetodit võimalik kasutada edaspidi võrkkooriku uurimisel ning katsetamisel.
Timber gridshells have several advantages: they are strong, they can cover large spans and they create a good architectural appearance in the environment. Although timber gridshells have several advantages, they are not very widespread yet. Problems related to them are studied in many institutes and simpler ways for designing them are searched for. The purpose of this thesis is to create a test piece of the gridshell and study the problems and the way it acts under the load test. The computer modelling of the shell was done with the program Rhinoceros 5 and the real gridshell was built after the computer model. The shell was loaded with a lever system of chains hanging from the nodes of the structure. A total station and a mini prism were used to measure the vertical and horizontal displacements of the shell under the loading. It became evident that this method was an effective way to study the displacements of the structure. The model shell had similar characteristics to the typical shell structure. Before the shell broke, it showed signs of large deformations and the breaking point could be foreseen. After the load was removed, the structure almost entirely restored its shape. The main problems were related to the timber frame which was constructed specially for fixing the laths in the holes of the frame. After applying the load the holes of timber frame were bruised and the structure deformed asymmetrically. Even so the presented method can be used to study and test the gridshells in the future.
Timber gridshells have several advantages: they are strong, they can cover large spans and they create a good architectural appearance in the environment. Although timber gridshells have several advantages, they are not very widespread yet. Problems related to them are studied in many institutes and simpler ways for designing them are searched for. The purpose of this thesis is to create a test piece of the gridshell and study the problems and the way it acts under the load test. The computer modelling of the shell was done with the program Rhinoceros 5 and the real gridshell was built after the computer model. The shell was loaded with a lever system of chains hanging from the nodes of the structure. A total station and a mini prism were used to measure the vertical and horizontal displacements of the shell under the loading. It became evident that this method was an effective way to study the displacements of the structure. The model shell had similar characteristics to the typical shell structure. Before the shell broke, it showed signs of large deformations and the breaking point could be foreseen. After the load was removed, the structure almost entirely restored its shape. The main problems were related to the timber frame which was constructed specially for fixing the laths in the holes of the frame. After applying the load the holes of timber frame were bruised and the structure deformed asymmetrically. Even so the presented method can be used to study and test the gridshells in the future.
Kirjeldus
Märksõnad
võrkkoorikud, puitkonstruktsioonid, siirded, koormus (tehn.), koormuskatsed, magistritööd