Vol. 4, No 2, 2006 pp. 127 - 138
UDC 624.016:624.011.1+624.012.3(045)=20
DESIGN OF CONNECTIONS IN
COMPOSITE TIMBER-CONCRETE STRUCTURES
Dragoslav Stojić, Radovan Cvetković
University of Niš, Faculty of Civil Engineering and Architecture, Serbia
Abstract. This work deals with composite timber concrete structures. By combining timber and concrete in new type of composite material and using the best properties both materials, the high tensile strength of a timber and the high compressive strength of a concrete, depending of different building conditions we can find a lot o reasons for decision to apply this type of the structure in comparison to concrete or steel structure. Here, design methods and procedures for determination of load bearing capacity bar-shaped connectors (fasteners) very often used as element connecting timber and concrete in composite structures will be given. The procedure will be exposed and explained according to the new fashioned methods collected as set of Euro-norms in Eurocode 5. The design equations in Eurocode 5 derived from Johansen's work are based on a rigid plastic behavior of the fastener under bending moments and the timber under embedding stresses and take into account the plastic moment capacity of the fastener.
Key words: composite timber concrete structures, load bearing capacity bar-shaped connectors Johansen's theory, Eurocode 5.
PRORAČUN VEZA U SPREGNUTIM KONSTRUKCIJAMA
TIPA DRVO-BETON
U radu su analizirane spregnute konstrukcije tipa drvo-beton. Kombinovanjem drveta i betona dobija se novi tip spregnutog materijala u kome se koriste najbolja svojstva oba materijala- visoka čvrstoća na zatezanje drveta i visoka čvrtoća na pritisak betona. U zavisnosti od različitih uslova građenja, postoji mnogo razloga za upotrebu spregnutih konstrukcija tipa drvo-beton u odnosu na mogućnost primene čelika ili betona. U radu su dati proračunski postupci za određenje nosivosti štapastih spojnih sredstava, veoma često korišćenih kao element za spajanje drveta i betona. Proračunski postupci su predstavljeni i objašnjeni u skladu sa novim računskim konceptom baziranom na graničnim stanjima nosuvosti i upotrebljivosti , tj Evrokodom 5. Računske jednačine u Evrokodu 5 izvedene na osnovu Johansenove teorije loma, bazirane su na kruto-plastičnom ponašanju štapastih spojnih sredstava pri savijanju, pritisku po omotaču rupe u drvetu vrednosti momenta tečenja spojnog sredstva.