# Engineering method for research of stress state in concentration areas of welded joints with symmetrical reinforcement

## Authors

• А. Moltasov Институт электросварки им. Е.О. Патона НАН Украины, Ukraine
• P. Tkach Институт электросварки им. Е.О. Патона НАН Украины, Ukraine
• S. Motrunich Институт электросварки им. Е.О. Патона НАН Украины, Ukraine

## Keywords:

welded joint, symmetrical reinforcement, stress state, stress concentration, transition radius from weld to the base metal, reliability area, hypothesis of broken cross sections

## Abstract

Abstract. Subject, theme, aim. The subject of research in this work is the stress distribution in stress concentration areas of welded
joints with double-sided symmetrical reinforcement. The topic of this work is related to development of engineering method of
describing the stress state in the transition areas of weld to the base metal of butt and cruciform welded joints. The aim consists in
establishing of mathematical relationships that describe the change of the first principal stress on the contour of the investigated area, and in the depth of the welded joint at tension and bending.
Method or methodology. In order to establish the equilibrium conditions which exist in the section of stresses at external force factors in the development of research method of stress state was used the hypothesis of broken cross sections. Mathematical
dependences which describe the stress distribution in the areas of concentration, and the formulas for determining of stress concentration factor was obtained by means of developed method, and the adequacy of these formulas was verified by numerical
calculation by finite element method.
Results. Using the formulas which corresponding to the tenets of the proposed method for butt-welded joints with a relative transition radius from weld to the base metal between 0,4 and 2,6 the SCF was calculated. Comparative analysis of the obtained results with the results of numerical calculation by finite element method showed that the maximum deviation for tension was 1,10%, and for bending it was 0,91%.
Field of application of the results. The formulas which obtained in the result of research can be used for the calculation of stress concentration factor in the butt and cruciform welded joints with a high value of the relative transition radius from weld to the base
metal.

## Author Biographies

### А. Moltasov, Институт электросварки им. Е.О. Патона НАН Украины

Отдел № 3 "Прочность сварных конструкций", старший научный сотрудник

### P. Tkach, Институт электросварки им. Е.О. Патона НАН Украины

Отдел № 3 "Прочность сварных конструкций", старший научный сотрудник

### S. Motrunich, Институт электросварки им. Е.О. Патона НАН Украины

Отдел № 3 "Прочность сварных конструкций", младший научный сотрудник

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2017-06-22

## How to Cite

[1]
Moltasov А., P. Tkach, and S. Motrunich, “Engineering method for research of stress state in concentration areas of welded joints with symmetrical reinforcement”, Mech. Adv. Technol., no. 1(79), pp. 82–90, Jun. 2017.

Original study