UPGRADING THE SEISMIC PERFORMANCE OF REINFORCED CONCRETE MASONRY COLUMNS USING CFRP AND GFRP WRAPS

摘要

Existing reinforced masonry structures would have reinforced concrete masonry (RCM) columns that are part of the structure's seismic force resisting system. Compared to reinforced concrete columns; few experimental studies have addressed the behaviour of rectangular masonry columns under combined axial and cyclic loads. Wrapping susceptible RCM columns with carbon fibre-reinforced polymers (CFRP) or glass fibre-reinforced polymers (GFRP) is expected to enhance their seismic behaviour, yet physical tests need to be conducted to quantify this enhancement. This paper focuses on assessing the seismic performance of RCM columns wrapped with CFRP and GFRP sheets. In this experimental study, seven 1.4 m reinforced masonry columns were constructed and tested when subjected to constant axial force and cyclic lateral excitations. The columns have a cross-section of 390 mm×390 mm and were constructed using bull-nosed concrete units. The first column had no FRP wraps and was used as a control specimen while three columns were wrapped with CFRP, and three columns were wrapped with GFRP using different layers of CFRP and GFRP sheets or different wrapping schemes. From the tests, the effects of CFRP and GFRP wraps in enhancing the seismic performance of the columns in terms of their ductility, and strength are discussed and compared.