Potential External Strengthening of Reinforced Concrete Beam Using Natural Fiber Composite Plate

Abstract

A study has been conducted to investigate the potential use of mengkuang leaves or Pandanus atrocarpus bonded with epoxy resin as external strengthening material for the strengthening of reinforced concrete (RC) beams. Physical and mechanical properties as well as structural properties of the mengkuang leaves-epoxy composite plates (MLECP) were evaluated in this study. Chemical treatment was performed on the dried mengkuang leaves using sodium hydroxide (NaOH) with concentrations of 2%, 5% and 8%. Scanning electron microscope (SEM) and flexural strength tests were conducted on the mengkuang leaves and flexural specimens, respectively. All the beams were tested to failure under four-point loading. Results showed that the flexural strength of the composite with 0.3 fiber volume ratio exhibited the highest flexural strength. Strengthening of RC beam using MLECP managed to increase the beam capacity.

Development of Enhanced Polymer Fiber Reinforced Concrete

“…Thus, fibers accumulating volume in the concrete beam but failing to increase the beam's flexural strength resulting in an overall drop in flexural strength of the PFRC beam. The roughness of the concrete surface helps the fibers to impregnate with high interfacial bond strength between concrete and fibers (Chin et al, 2018). At high weight fraction 0.20 wt.…”

“…It measures the workability of fresh concrete (Ashraful and Riyami, 2018). A concrete mixture by weight with appropriate water/ cement ratio is maked in the laboratory and requisite for casting six cubes after performing slump test (Chin et al, 2018). Figure 1a shows the procedure for sampling the slump test.…”

Natural fibres and biopolymers in FRP composites for strengthening concrete structures: A mixed review

“…As the tension steel in the beam midspan reaches its yield stress and begins to rotate, the steel yielding progresses towards the unstrengthened beam and a crack is formed at the end of the FRP laminate; this is then followed by flexural-shear failure. This failure can be observed in [81] and [82]. The failure modes designated by Cc start to occur from below the tension steel and are characterised by a more abrupt failure.…”

“…Several fibre treatments have been used to modify this fibre property. Alkaline [71,76,81,82,[92][93][94] and heat [6,89,96,97] were the predominant fibre pre-treatment used. Alam and Riyami [92] pre-treated jute and kenaf fibres with heat NaOH, and though the treatment reduced the water absorption [142] of the developed NFRP laminates, the strengthening effect of the treated NFRP laminates on RC beams was less than the untreated ones.…”

Strengthening of Reinforced Concrete Beams Using Bamboo Fiber/Epoxy Composite Plates in Flexure

“…The aforementioned issue spurs research on the utilization of natural fiber from agricultural plants such as kenaf, jute, sisal as composite material, which is eco-friendly and cost-effective. Recently, various investigations were performed on kenaf fiber [8], jute [9,10], PALF [11] and mengkuang leaves [12] composite to study their mechanical properites as well as their potential as external structural strengthening material. However, the use of bamboo fiber, especially as a bamboo fiber composite plate for structural strengthening is still limited.…”