Analysis of spiral reinforcement in grouted pipe splice connectors

Vlačni otpor injektiranog cjevastog spoja ovisi o interakciji spoja između armaturnih šipaka, cjevastog naglavka i injekcijske smjese. U radu su prikazani rezultati dobiveni ispitivanjem 21 uzorka injektiranih spojeva koji su opterećeni rastućim osnim opterećenjem sve do sloma. Svaki cjevasti spoj sastojao se od čelične cijevi, spiralne armature s vertikalnim šipkama i cementne injekcijske smjese. Analiziran je utjecaj koraka spiralne armature od 15, 25 i 35 mm na odnos naprezanja prianjanja i proklizavanja. Najbolji rezultati injektiranih cjevastih spojeva postignuti su kod koraka spiralne armature od 15 mm te četiri vertikalne šipke koje djeluju kao posmični klinovi.Tensile resistance of a grouted splice connector depends on the interaction between reinforcement bars, sleeve and grout. Results for 21 grouted splice connectors which were tested until failure under an increasing axial load are presented in the paper. Each splice connector consisted of a steel pipe, steel spiral with vertical bars, and cement grout. The effects of spiral pitch distance of 15, 25 and 35 mm on the bond stress to slip relationship were evaluated. The best performance of grouted pipe splice connectors was obtained at the spiral pitch distance of 15mm, combined with the use of four vertical bars as shear keys