Probability-based Design of Spun Concrete Beam-columns

The attention of engineers is turned to the application of precast spun concrete columns reinforced by high‐strength steel bars for office and administrative buildings. The paper discusses a possibility of using the reliability index approach to designing beam‐columns of building frames and analyses resistance criteria for beam‐columns of annular cross sections as compression members with bending moments and bending members with compressive forces. First and second order effects of beam‐columns are considered. The article also presents time‐dependent resistance safety margin and its stationary equivalent and investigates the unsophisticated applied models for probability‐based design of frame beam‐columns. The design of a beam‐column of the braced frames is illustrated providing a numerical example. Santrauka Atkreiptas inžinieriu demesys i didžiastiprio plieno strypais armuotu sijiniu kolonu iš centrifuguotojo betono naudojima istaigu ir administraciniuose pastatuose. Aptarta galimybe projektuojant pastato remo sijines kolonas taikyti patikimumo indekso būda. Analizuojamas sijiniu kolonu kaip lenkiamai gniuždomu ir gniuždomai lenkiamu žiedinio skerspjūvio ele‐mentu atspario kriterijus. Nagrinejamos sijiniu kolonu pirmosios ir antrosios eiles iražos. Pateiktas laike kintantis ribines saugos atsparis ir jo stacionarusis ekvivalentas. Tyrinejamas nesudetingas taikomasis modelis remo sijiniu kolonu ti‐kimybiniam projektavimui. Skaitiniu pavyzdžiu iliustruojamas stabilizuojamu remu sijines kolonos projektavimas.