Behavior of Timber Beams Strengthened by Jute Fibers

Abstract

The study involves strengthening timber beams by known jute fibers with various forms of strengthening and comparison the bending test results with the control beams and beams strengthened by steel plates. Twenty-two timber specimens with dimensions (70×100×1000) mm are divided into eight groups and loaded under a one-point load. The work is carried out to study the flexural and shear strengthening effects on behavior of the tested beams. Four specimens wrapped in U technique in single and double layers, along the whole length of the beam in full and strips wrapping technique, seven beams bonded in full and spiral configuration, seven timber specimens wrapped in flexural strengthening technique with single and multiple layers, and two samples strengthened by steel plates. The results show that jute fibers strengthening are improved the ultimate loads of timber beams by between (30%-101%) compared with the control beams for different types of strengthening and by about (80%, 85%) using steel plates strengthening. On the other hand, the mid-span deflection are decreased by between (28%-45%) at the same load. Furthermore, it is found that the highest ultimate load deflection is when the beam wrapped in full strengthening technique. The ductility, stiffness, toughness at yield load and toughness at ultimate load are increased by between (21%-51%), (10%- 73%), (45%-373%), and (57%-401%), respectively. The jute fibers strengthening have high elasticity performance and prove that the jute fibers materials have a large potential to act as a structural strengthening material.