Experimental and numerical analysis of timber framed wall elements with openings

Doktorska disertacija obravnava panelne stene, izdelane iz lesenega okvirja in enoslojnih mavčno-vlaknenih obložnih plošč, ki vsebujejo odprtino za okno ali vrata. Disertacija je usmerjena v nadaljevanje raziskovalnega dela, izvedenega v zadnjih letih na področju analize nosilnosti za prevzem vodoravnih obtežb montažnih stenskih elementov brez odprtin. Obravnavani stenski elementi predstavljajo sovprežne konstrukcije, sestavljene iz lesenega okvirja in obložnih plošč, ki so na okvir pritrjene z mehanskimi veznimi sredstvi - sponkami. Osnovni namen disertacije je določiti vpliv dimenzij odprtine na nosilnost in togost stenskega elementa. V okviru razsikave smo izvajali eksperimentalne teste nosilnosti in numerične analize s pomočjo računalniških izračunov po metodi končnih elementov. Numerično analizo smo izvajali z dvema komercialnima programskima paketoma za analizo konstrukcij: TNO Diana in SAP 2000. Primerjava rezultatov numeričnih analiz z rezultati eksperimentalnih preiskav je pokazala dobro ujemanje. Glede na rezultate zaključujemo, da imajo stenski paneli z odprtinami lahko pomemben vpliv na togost in nosilnost montažnih stenskih sistemov, ki ga ni primerno zanemariti. Lastne eksperimentalne in numerične rezultate smo primerjali z rezultati treh metod iz literature, in sicer z Metodo B povzeto po Evrokodu 5, z metodo, uporabljeno za stenske elemente z lesnimi obložnimi ploščami in z metodo, uporabljeno za križno lepljene masivne KLH stene. V splošnem nobena izmed primerjalnih metod ni uporabna za obravnavane stenske panele z mavčno-vlaknenimi obložnimi ploščami, kar nakazuje pomanjkanje podatkov za projektiranje tovrstnih konstrukcij v inženirski praksi.The Ph.D. thesis deals with timber framed wall elements coated with single fibre plaster boards (FPB), containing an opening for a door or window. The thesis represents a continuation of the research work on the horizontal load-bearing capacity of prefabricated wall elements without openings, realized in the recent years. The considered wall elements represent composite structures composed of a timber frame and the sheating boards which are attached to the frame by mechanical fasteners-staples. The main purpose of the thesis was to determine the influence of the opening on the load-bearing capacity and stiffness of the wall element. For the purpose of the research both the experimental load tests as well as the numerical analyses using the computer calculations by the finite element method (FEM) were carried out. The numerical analyses were performed using two commercial FEM computer programmes: TNO Diana and SAP 2000. The comparison of the results of the numerical analyses with the results of the experimental tests showed a good coincidence. Based on the results we conclude that the wall elements with openings may have an important impact on the stifness and capacity of wall sistems and thus their contribution should not be ignored. The experimental and numerical results were also compared to three methods from the literature: the Method B from Eurocode 5, the method used for plywood-sheated timber-frame wall elements and the method used for solid X-lam timber wall elements. In general none of the comparative methods proved to be applicable to the considered FPB-sheated wall elements which indicates a lack of suitable data for the design of such structures in engineering practice