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Semi rigid mounting joints of glued laminated timber elements are connections that are fully assembled on construction site and capable to handle bending moments, axial and shear forces. The need for new type of semi rigid timber elements’ connection is obvious. The manufacturing possibilities of glued laminated timber elements’ are wide: straight element's length may extend up to 40 m or curved axis elements with dimensions of up to 10 meters in height, therefore, manufacturers, erectors and others face with transportation problems of non-standard, oversized elements. Semi-rigid mounting joints are used to solve this problem. In factory non-standard, oversized, glued, laminated timber elements are cut into standard transportation dimensions and fully mounted into integral element on construction site, using semi rigid mounting joints. In this article semi-rigid, glued, laminated timber elements’ joints which are used as beam to beam, beam to column and column to foundation connections are analysed. Also the main design principles of semi-rigid joints are discussed. The new type of semi rigid beam to beam connection is proposed and experimentally analysed. The experimentally and theoretically analysed connection is composed of welded steel details which are anchored into timber element. The main experiment is four point bending; the analysed connection is in the middle of the span. The beam's span is 3.20 m; the dimensions of the timber element's cross section are: width 200 mm; height 400 mm; mounting bolts are M16. Glued laminated timber strength class is GL24h. The tight contact between timber element and steel detail is created by anchoring steel detail's T shape part into timber element. The initial movement between timber element and steel detail is eliminated using fillers. Two types of fillers are used in these experiments: two component polyurethane and cement based filler with polymer fibres. Two joints with different fillers are tested in laboratory experiments. Bending bearing capacity and stiffness (displacements) of the joints’ are determined in laboratory. Experimental bearing capacities are compared with theoretical calculations according to European (EC5) and Lithuanian timber structures design codes. Conclusions and recommendations are presented for further experiments and computer simulations. Santrauka Straipsnyje analizuojami pusiau standūs montuojamieji klijuotosios medienos konstrukcijų mazgai, kurie naudojami elementams sujungti per ilgį, rėmų kampinėms jungtims tarp kolonos ir sijos bei jungtims tarp kolonos ir pamato. Aptariami pagrindiniai pusiau standžių montuojamųjų medinių konstrukcijų mazgų konstravimo principai. Pasiūlytas ir eksperimentiškai tirtas per ilgį sujungtų lenkiamųjų klijuotosios medienos sijos elementų mazgas. Mazgas įrengiamas naudojant plienines detales, suvirintas iš lakštinio plieno, kurios inkaruojamos medienos elementuose. Kontaktas tarp medienos ir metalo užtikrinamas ir pradinis mazgo slankumas panaikinamas užpildant tarpus tarp medienos ir metalo užpildu. Pasirinkti du skirtingo pagrindo (sudėties) užpildai: dviejų komponentų poliuretano ir cementinis, kurio sudėtyje yra polimerinių plaušų. Nustatytas cementinio užpildo lekiamasis ir gniuždomasis stipriai. Eksperimentinės jungčių laikomosios galios palyginamos su teoriniais skaičiavimais pagal Lietuvos ir Europos medinių konstrukcijų projektavimo normas. Pateikiamos išvados ir rekomendacijos tolesniems tyrimams. Reikšminiai žodžiai:klijuotosios medienos elementų jungtys,elementų sujungimas per ilgį,sijos elementų tarpusavio jungtys,klijuotosios medienos rėmai

The article discusses the main methods for steel threaded rods pasted into timber. Single – threaded steel rod carrying capacity glued onto glulam (timber cross section – 100 x 100 mm, threaded rod – M12 and M16) has been experimentally determined. Behaviour based on the experimental results of two different methods for pasting rods into timber has been summarized: the first threaded steel rod was glued into 4 mm bigger diameter hole while the second – rod chased into 2 mm smaller diameter hole. The conducted experiment used 800 mm length glulam beams; threaded steel rods were glued to both ends of specimens (equal theoretical carrying capacity). The experiment in the tension of both ends was carried out. The obtained results were compared with theoretical expressions submitted in EC 5 – 1 – 1:2005 and STR 2.05.07:2005. The main dependences of geometrical parameters and carrying capacity have been provided. The main collapse forms of specimens and manufacturing defects having influence on the final carrying capacity and behaviour of the joint have been observed. Using the first method, a failure in the pasted rod occurs suddenly when timber splits along the fibre; in the second case, a failure is plastic when timber is compressed under thread. Additional experiments must be carried out using the first technology increasing the class of the strength of the pasted rod as under the maximum length of paste, in all cases, failure in the pasted rod occurred when a steel bar cracked. Along with an increase in the diameter of the rod, the dispersion of the results of the affixed slender part is increasing. Maximum variation in the results of applying the first method is 10%, whereas the second method of attaching makes 50%. Compared to the first method of attaching, the results of theoretical bearing capacity indicate that tests have an adequate margin which is equal to or is more than 2,0. A comparison of the second method of attaching results to theoretical bearing capacity makes clear that the experimental results of the tests have too low safety factor and in some cases are less than 1.0. This is due to the fact that the counting of attaching technology in some cases must be based on local compressed timber strength. The experimental study of two different methods for attaching steel bars reveals that the first method can be used in design practice considering both documents STR 2.05.07:2005 and EC 5-1-1:2005. The second method of attaching must be developed to ensure smooth rod surface coating adhesive. Attaching the second method should also be created in the exact form corresponding to the disintegration of the calculation model. Article in Lithuanian. Jungties tarp įklijuoto plieninio sriegtojo strypo ir medienos elgsenos tyrimas Santrauka.Straipsnyje aptariami pagrindiniai plieninių sriegtųjų strypų įklijavimo medienoje metodai. Eksperimentais nustatytos pavienių plieninių sriegtųjų strypų (M12 ir M16), įklijuotų medienoje, jungčių laikomosios galios. Apibendrinta dviejų skirtingų įklijavimo metodų (pirmasis – strypas įklijuojamas į 4 mm didesnio skersmens kiaurymę; antrasis – strypas įsriegiamas į 2 mm mažesnio nei strypas skersmens kiaurymę) elgsena remiantis eksperimentinių tyrimų rezultatais. Pagrindiniam eksperimentui naudoti klijuotosios medienos elementai (skerspjūvio matmenys – 100×100, ilgis – 800 mm), kurių galuose lygiagrečiai su medienos pluoštu buvo įklijuoti sriegtieji plieniniai strypai. Atliktas abipusis tempimo bandymas apkrovą perduodant strypams. Eksperimentinių tyrimų rezultatai lyginami su teorinės laikomosios galios skaičiavimais, atliktais pagal Lietuvos ir Europos medinių konstrukcijų projektavimo normų taisykles. Pateiktos jungties laikomosios galios ir geometrinių parametrų priklausomybės. Aptartos pagrindinės bandinių suirimo formos ir gamybos netikslumai, turėję įtakos jungties laikomajai galiai. Reikšminiai žodžiai: medienoje įklijuoti strypai, įtempių pasiskirstymas medienoje, medienos jungtis. First Published Online: 16 May 2013

Steel storage tanks and other structures of such kind of buildings have been extensively designed following the requirements of continuous cyclic operations. Because of many economically based reasons any engineering inspections of a huge volume are very expensive, so numerical investigations of the local defects are practically important. Natural inspection of tank dents (volumes of tanks were from 1 000 to 50 000 m3, diameter of dents from 0,40 to 4,50 m, a depth up to 120 mm) has shown that analytical approach of their investigation by using existing design standards is rather complicated. The main objectives of the presented investigations are: to determine an appropriate size of the finite element for geometrical defect modelling on thin wall of the steel cylindrical tank; to identify stress/strain state by using finite element method in the place of the defect; to define the appropriate results of the proposed analytical solutions and requirements of the codes with FEM results. The results, derived from the proposed formulas, are compared to those of natural inspection of real tanks and also with the results obtained by numerical modelling using the finite element method. Netiesinių skaitinių baigtinių elementų modelių taikymas plonasienių plieninių cilindrinių talpyklų minkÅ¡tiesiems defektams įvertinti Santrauka PlieninÄ—s talpyklos ir tokio tipo inžineriniai statiniai projektuojami, atsižvelgiant į ilgalaikÄ™ jų eksploatacijÄ…. Didelių statinių remontas ir profilaktinÄ— priežiÅ«ra yra gana brangÅ«s procesai, todÄ—l svarbus talpyklų defektų skaitinis tyrimas. Talpyklų minkÅ¡tųjų defektų natÅ«riniai stebÄ—jimai (stebÄ—tos talpyklos nuo 1 000 iki 50 000 m3 , sÄ…lyginis defektų skersmuo nuo 0,40 iki 4,50 m, gylis iki 120 mm) parodÄ—, kad normavimo metodikos yra netikslios. Å iame darbe siekiama parinkti tinkamÄ… baigtinio elemento dydį plonasienių plieninių cilindrinių talpyklų geometriniams defektams modeliuoti taikant baigtinių elementų metodÄ…, nustatyti įtempių ir deformacijų bÅ«vį defekto vietoje, palyginti siÅ«lomus analitinius sprendimus bei standartų reikalavimus su baigtinių elementų metodo rezultatais. SiÅ«lomos iÅ¡raiÅ¡kos tikrinamos gretinant realių objektų skaiÄiavimo ir natÅ«rinių stebÄ—jimų rezultatus. Geometrinių defektų mechaninis bÅ«vis papildomai modeliuojamas baigtinių elementų metodu. Raktiniai žodžiai: plieninÄ— cilindrinÄ— talpykla, defektas, skaitinis modelis, baigtinis elementas, geometrinis netiesiÅ¡kumas, fizinis netiesiÅ¡kumas, įtempių ir deformacijų bÅ«vis First Published Online: 14 Oct 2010

In all branches of industry, especially in power-engineering, thin wall steel structures are extensively used. Land vertical cylindrical steel tanks are very popular ex-amples of such structures. Manufacture and assembling of these structures are usually accompanied by the deviations from a perfect cylindrical form. Therefore, exact evaluation of real local imperfections and common deviations from the analytical model of the tank is very important for such potentially dangerous structures. The main objectives of the presented investiga-tions are: to describe some results of experiments of thin plates with a defect; to identify stress and strain state by using the finite element method; to make the comparison between experimental results and FEM results. The final remarks and conclusions have been presented.