Compression resistance of short LBL columns with local damage after retrofitting using basalt fiber reinforced polymer

Abstract

Laminated bamboo lumber (LBL) are prone to local damage during long-term use and would require appropriate retrofitting for continued safe use in structures. The current paper examines a simple retrofitting technique using small bamboo pieces and basalt fiber reinforced polymer (BFRP) wrap to strengthen locally damage LBL columns. The effect of fiber orientation of the small LBL block has been experimentally evaluated by conducting compression tests on 15 specimens in 5 groups representing various combinations of LBL block and BFRP wrap. Test results showed that the ultimate bearing capacity of the damaged short LBL column was significantly reduced as the local damage induced obvious eccentric stress conditions resulting in premature failure of the short LBL column. When the damaged part of short LBL columns was retrofitted by using small LBL pieces with fibers in parallel to the original column fiber direction and was wrapped with BFRP sheet, and its compressive resistance was restored and the ductile performance also improved.