The limit state design of spun concrete columns using load combinations recommended by EN 1990 and ASCE/SEI 7–05

Abstract

The expediency of using precast spun concrete columns of annular cross‐sections reinforced by high‐strength steel bars is discussed. Test material properties, efficiency factors and resisting compressive stresses of plain and reinforced spun concretes are presented. Modelling a bearing capacity of eccentrically loaded members of annular cross‐sections is based on the concepts of compression with a bending moment and bending with a concentrical force. The comparison of test and modelling data of concentrically and eccentrically loaded members is analysed. The expediency to use in design practice the approaches of current methods of partial safety factors design (PSFD) legitimated in Europe and load and resistance factors design (LRFD) suggested in the USA and other countries is considered and illustrated by a numerical example.

Santrauka

Aptariamas didžiastiprio plieno strypais armuotu žiedinio skerspjūvio centrifuguotojo betono kolonu naudotinumas. Pa‐teiktos armuotojo ir nearmuotojo centrifuguotojo betono medžiagu savybns, efektyvumo veiksniai ir laikomieji gniuždy‐mo itempiai. Ekscentriškai gniuždomu žiedinio skerspjūvio elementu laikomajai galiai modeliuoti taikomos lenkiamojo gniuždymo ir gniuždomojo lenkimo sampratos. Analizuojamas centriškai ir ekscentriškai apkrautu elementu eksperi‐mentiniu ir modeliavimo duomenu sugretinimas, nagrinnjamas Europos, JAV ir kitu šaliu projektavimo praktikoje itei‐sintu ir paplitusiu daliniu veiksniu ir apkrovu bei atspariu veiksniu metodu taikymo tikslingumas, kuri rodo skaitmeninis pavyzdys.

Keywords:

• spun concrete
• high‐strength steel
• beam‐columns
• compression test
• eccentric loading
• limit state design

Reikšminiai žodžiai::

• centrifuguotasis betonas
• didžiastipris plienas
• gniuždymo bandymas
• ekscentrinis apkrovimas
• ribiniu būviu metodas