Strengthening of pre-damaged concrete cylinders using post-tensioned steel straps

Abstract

The effectiveness of an innovative post-tensioned steel strapping strengthening solution for enhancing the behaviour of pre-damaged plain concrete cylinders was investigated. To achieve this, 24 cylinders of diameter 100 mm and height 200 mm were subjected to axial compression; 18 of these specimens were initially subjected to compressive load in unconfined conditions to produce three different damage levels. These pre-damaged specimens were then repaired and strengthened using different strap spacings and number of confining layers of straps. The results showed that the post-tensioned steel straps were extremely effective at enhancing the strength of the pre-damaged specimens, by up to 313%. The strapping also increased the axial deformability of the pre-damaged cylinders up to values of 2·64–2·95%. However, the effectiveness of the repair solution varied with the pre-damage level. The results of this work should contribute towards the development of more rapid and effective strengthening solutions for damaged reinforced concrete structures.