Study On Mechanical Performance Of Stainless Steel K-joints With CHS Brace-to-SHS Chord

Stainless steel is becoming more and more popular in modern building structures because of its attractive appearance,better corrosion resistance,excellent durability,easy maintenance and cheap cost in full using life,especially in some of key structures and key parts of structures.And the steel tube joint is widely used due to its good mechanical behavior,clear force transmission line and larger bearing capacity.The joints with circular brace and square or rectangular chord meet the requirements of structure and mechanical properties much more.So,stainless steel tube joints with circular brace and square chord have a broad application prospect.While,the research of stainlesss steel joints with circular brace and square chord especially K-joints is scarce in our country,which hinders the application of stainless steel structure in structure engineering to some extent.In this paper,with reference to the research on steel tube joints conducted by domestic and foreign scholars,static experimental study of stainlesss steel K-joints with circular brace and square chord was conducted to research the failure modes and ultimate strengths.Based on the test,the accurate and effective finite element models were built to analyse the influence of geometrical paprmeters on the failure modes and ultimate strengths,which included the brace diameter to chord width ratio ?,chord width-to-thickness ratio 2?,brace thickness-to-chord thickness ratio ? and overlap rate of overlap joints Ov.In addition,the current formulae for the ultimate strength of joints in Chinese steel structure standard were modified in this paper.The modified formulae were appropriate for the ranges of geometrical paprmeters involved in this paper,providing some reference for future design and research of stainlesss steel K-joints with circular brace and square chord.