Experimental study on the compression behavior of long timber column strengthened with the novel hybrid fiber sheets

Abstract

Abstract Long timber columns are widely used in traditional timber structures worldwide; however, many of them possess bearing capacity issues and have to be strengthened. The current study aims to develop the novel Hybrid fiber reinforced polymers (HFRP) sheets suitable for long timber columns. In the first stage, six HFRP sheets were designed, and the evaluation of these sheets was carried out by the tensile tests and the Scanning electron microscopy (SEM) tests. Secondly, for the compression test, two sets of 36 timber columns were designed utilizing six types of HFRP sheets. Finally, the effects of different sheet types and strengthening methods on the compressive performance of timber columns were investigated. The findings reveal that bidirectional HFRP sheets have excellent compressive performance for timber columns. In the case of using one-layer interval reinforcement, the bearing capacity can be increased by 22.27%, which is 12.15–17.81% higher than that of the unidirectional HFRP sheets. Compared with one-layer reinforcement, the two-layer reinforcement increased from 0.91% to 5.35%. The current study's findings are intended to provide an essential scientific foundation for the advancement of fiber-reinforced timber column technology and the preservation of the heritage of timber structures.

Keywords

• Long timber column
• Hybrid fiber sheet
• Mechanical properties
• Compression test
• Scanning electron microscopy