Uporaba steklenih panelov za potresno varno gradnjo objektov

doktorska disertacija

David Antolinc (Author), Roko Žarnić (Mentor), Matjaž Mikoš (Thesis defence commission member), Jože Lopatič (Thesis defence commission member), Vlatko Bosiljkov (Thesis defence commission member), Vojko Kilar (Thesis defence commission member), Vlatka Rajčić (Co-mentor)

Abstract

Na področju projektiranja steklenih fasad obstaja omejeno število strižnih preiskav v njihovi ravnini in s tem včasih pomanjkljivo znanje o njihovem dejanskem ravninskem obnašanju. Slednje je predvsem pomembno, kadar je steklena fasada izpostavljena potresni obtežbi, ki vsili konstrukciji etažne pomike, s čimer lahko vpliva na steklene panele. Prekomerna obremenitev steklenih panelov predstavlja veliko nevarnost za uporabnike objekta predvsem zaradi krhke narave stekla. V disertaciji je predstavljen inovativen kompozitni strižni panel sestavljen iz lameliranega lesenega okvirja in zavetrovanja iz dvojnega delno kaljenega lameliranega stekla, ki ima funkcijo prevzemanja obremenitev, ki izvirajo iz horizontalnih obtežb. Stik med lesom in steklenim panelom je izveden brez adhezivnih sredstev s čimer je omogočeno omejeno drsenje steklenega panela v lesenem okvirju. Za obravnavane kompozitne strižne panele smo izvedli šest monotonih in šest cikličnih kvazi-statičnih preiskav v laboratoriju Fakultete za gradbeništvo in geodezijo, Univerze v Ljubljani. Na Inštitutu za potresno inženirstvo in seizmologijo IZIIS v Skopju smo v sklopu glavnih preiskav, izvedli še dinamične teste na potresni mizi za dva vzporedno postavljena kompozitna panela z uporabo različnih zapisov pospeškov realnih potresov. Za podrobnejšo analizo in razumevanje obnašanja celotnih kompozitnih panelov smo izvedli še vrsto spremljevalnih preiskav odziva upogibno in tlačno obremenjenega lameliranega stekla, razvoja sile trenja med lesom in steklom, nosilnosti spojev lesenega okvirja in mehanskih karakteristik lesenega okvirja. Preizkušeni kompozitni paneli se med seboj razlikujejo v detajlih spojev lesenih okvirjev in robnih pogojev na mestih vpenjanja. Za interpretacijo histereznega odziva panelov smo nadgradili program HISPA+, ki nam omogoča izvrednotenje duktilnosti, upadanja togosti, nosilnosti in koeficienta ekvivalentnega viskoznega dušenja histereznih zank. Rezultati eksperimentalne analize kažejo na dokaj robustno obnašanje obravnavnih panelov in predvsem na veliko disipacijo energije po zaslugi sile trenja med steklenim panelom in lesenim okvirjem. Predstavljen je tudi poenostavljen bilinearen model za odziv na vrhu kompozitnega panela, katerega smo kasneje uporabili v poenostavljeni analizi ravninskega tri etažnega lesenega okvirja za preverjanje stabilizacijskega učinka na okvirno konstrukcijo. Izkaže se, da imajo obravnavani kompozitni paneli velik potencial pri sodelovanju prevzemanja potresne obtežbe ob zavedanju, da so za potrditev le tega potrebne še obsežne parametrične analize.

Keywords

gradbeništvo;disertacije;konstrukcijsko steklo;lamelirano steklo;leseni okvirji;potres;dušenje;ciklična obremenitev;histerezni odziv;trenje;strižni paneli;

Data

Language:	Slovenian
Year of publishing:	2014
Typology:	2.08 - Doctoral Dissertation
Organization:	UL FGG - Faculty of Civil and Geodetic Engineering
Publisher:	[D. Antolinc]
UDC:	624.011.1:666.155(043.3)
COBISS:	6491745
Views:	2726
Downloads:	595
Average score:	0 (0 votes)
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Other data

Secondary language:	English
Secondary title:	Use of laminated glass panels for earthquake resistant building design
Secondary abstract:	There are a limited number of in-plane shear racking tests in the field of glass facades design and the designer is sometimes faced with the lack of knowledge about their actual in-plane behavior. This is particularly important for the glass facades exposed to the seismic load, which imposes story drifts to the main structure and hence to the glass panels which can pose a significant risk to users. The dissertation presents an innovative composite shear panel composed of laminated timber frame and a double heat strengthened laminated glass, which has the function of taking over of the horizontal loads. The contact between timber frame and glass panel is made adhesiveless which consequently enables sliding of glass panels within timber frame. We conducted six monotonous and six cyclic quasi-static racking tests in the laboratory of the Faculty of Civil and Geodetic Engineering, University of Ljubljana. Full dynamic tests have been also conducted at earthquake institute IZIIS in Skopje for two parallel composite shear panels for different earthquake acceleration records. For detailed analysis and understanding of the behavior of the considered composite shear panels, we carried out a series of complementary experiments to capture the response of laminated glass to bending and compression loads, the development of friction force between timber and glass, load bearing capacity of different joint details and mechanical characteristics of the timber frame. Three different types of composite shear panel specimens are tested for three possible boundary conditions. For the interpretation of the hysteresis response we upgraded software HISPA+, which enables us to evaluate ductility, stiffness degradation and the equivalent viscous damping coefficients. The results are showing robust behavior of tested panels and particularly high energy dissipation level due to the friction between the glass panels and timber frame. Simplified bilinear model for the displacement response at the top of the composite panel is introduced which was later used in the analysis of the simplified three stories timber frame model for evaluating of the stabilizing effect on the frame structure. The results are showing that considered composite panels have high potential in sharing of the earthquake imposed load where one must be aware of the fact that further parametric analysis must be done for broader acceptance of this statement.
Secondary keywords:	civil engineering;thesys;structural glass;laminated glass;timber frame;earthquake;damping;racking test;hysteresis response;friction;shear wall;
URN:	URN:NBN:SI
File type:	application/pdf
Type (COBISS):	Dissertation
Thesis comment:	Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo
Pages:	XXII, 168 str., [70 str.] pril.
ID:	8726622