Naponska analiza ugaonih zavarenih spojeva nosača konstrukcija savremenim numeričko-eksperimentalnim pristupom
Stress analysis of corner welded joints structure by modern numerical-experimental approach
Author
Nagiar, Hasan MehdiMentor
Maneski, Taško
Committee members
Sedmak, Aleksandar
Milošević-Mitić, Vesna

Ignjatović, Dragan
Gubeljak, Nenad
Metadata
Show full item recordAbstract
Otvoreni i zatvoreni tankozidi preseci imaju široku primenu u industrijskim aplikacijama za
dizajn mnogih mašina i strukturnih komponenti. Ove komponente su često fabrikovane
zavarivanjem, a ne livenjem ili kovanjem. Tankozidi profili su obično povezani pomoću
ugaonih zavarenih spojeva. Takvi spojevi su takođe korišćeni u drugim inženjerskim
aplikacijama kao što su građevinske mašine, mostovi, ramovi, šasije vozila i dr.. U ovoj
disertaciji ponašanje zatvorenih profila (kutija, okrugla cev) i otvoreniih profila (L, Z, C i K
profili) šavnih profila, proučavani su tako što su izlagani statičkim opterećenjima i
numeričko-eksperimentalnim pristupom.
Sa tačke gledišta strukturne analize, uprkos široko rasprostranjenim ugaono zavarenim
spojevima koji efikasno nose opterećenja na elementima, ne postoji praktičan, jednostavan i
precizan pristup za njihov dizajn i analizu. U tu svrhu , inženjeri često moraju pripremiti
relativno komplikovan model konačnih elemenata ploče ili zapremine. To je za...to što
navedeni eleementi izloženi opštim opterećenjima proizvode koncentracije napona u blizini
spojeva. Jedan od doprinosa ovog istraživanja je bolje razumevanje ponašanja ugaono
zavarenih spojeva izloženi naprezanju savijanja i naprezanja savjanja sa uvijanjem. Primena
metode konačnih elemenata predstavlja osnovni numerički pristup. Posmatrani profili su
medelilrani različitim konačnim elementima (greda, ploča i zapremina) i sa različitim
slučajevima opterećenja. Primećuje se da na kratkom rastojanju od spoja putem ugaono
zavarenih spojeva struktura nosećeg elementa pod izloženim opterećenjem ponaša se kao
greda.
Zavareni spojevi su generisani različitim tehnikama modelrianja sa primenom različitih
tipova i veličina konačnih elemenata elemenata. Kompletni rezultati deformacija su, takođe,
eksperimentalno dobijeni pomoću tehnike primene korelacije digitalne slike (DIC).
Eksperimentalni testovi se izvode za proveru numeričkih simulacija u cilju ispitivanja
mehaničkih performansi zavarenh spojeva izloženi kombinovanim opterećenjima. Rezultati
numeričkog prroačuna pokazuju dobro slaganje sa eksperimentalnim rezultatom .
Hollow and non hollow section members are widely used in industrial applications for the
design of many machine and structural components. These components are often fabricated
by welding rather than by casting or forging. For example, in agricultural machinery, the
hollow tubes are typically connected together through welding to form a corner welded joints.
Such joint connections are also employed in other engineering applications such as
construction machinery, offshore structures, bridges, and vehicle frames. In this dissertation,
the behavior of tubular (box and circle profile) and non tubular (L, Z, C and X profiles) joint
connections profiles, subjected to static loads were studied both experimentally and
numerically.
From a structural analysis point of view, despite of the wide use of corner welded joints as
efficient load carrying members, there is no available practical, simple and accurate approach
for their design and analysis. For this purpose, engineers must often prepare ...relatively
complicated and time consuming Finite Element models made up of shell or solid elements.
This is because unlike solid-section members, when hollow section members are subjected to
general loadings, they may experience severe deformations of their cross-sections that results
in stress concentrations in the connection’s vicinity. One of the objectives/contributions of
this research work is the better understanding of the behavior of the corner welded joint
connections under out-of- plane bending and torsion loading conditions. Through a detailed
Finite Element Analysis (FEA) using shell and solid elements, the stress distribution at the
connection of the tubular and non tubular corner welded joints were obtained for different
loading conditions. It is observed that at a short distance away from the connection of the
corner welded joints, the structure behaves similar to beams when subjected to loadings.
Finite element models with different modeling techniques and meshing with various size and
types of elements were created and analyzed. The full displacement field results were
obtained experimentally by using the digital image correlation (DIC) technique. Experimental
tests were performed to validate numerical simulations in order to investigate the mechanical
performance of a series of fillet-welded connections under combined loading. The full
displacement field results show good agreement comparing with the experimental results...