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This paper presents the findings of an experimental study to investigate the structural behavior of reinforced concrete (RC) beams externally strengthened with various types of kenaf fiber reinforced polymer composite laminates with 50% fiber volume content. The experimental parameters including flexural strength, stress-strain relationship, deflection, tensile stress and young modulus of beams strengthened by different kenaf fiber reinforced polymer composites are discussed. In order to test the flexural strength of the RC beams, a total of eight beams divided into two series were used. In each series, every two of the beams were strengthened with kenaf/epoxy, kenaf/polyester, and kenaf/vinyl ester composite laminates respectively. The remaining two were kept as control specimens. The experimental moment capacity of each beam was calculated using tensile strength and young modulus of the composites. Comparisons were made on the load-deflection, strain behavior and failure mode. Moreover, theoretical moment capacity of each beam was calculated using conventional formulation to verify experimental results. The research findings indicated that all strengthened beams improved structural performance where the maximum flexural strength increase by 40% and maximum deflection reduced by 24%.

Natural fiber is usually used as reinforcement in polymeric materials, and short fibers are commonly used for non-structural applications. However, the lack of studies on long fiber reinforced polymeric materials, especially kenaf fiber, has limited its usage in Malaysia. This paper presents the experimental results of a series of tensile tests conducted on continuous kenaf fibers produced with different types of thermoset resin (epoxy, polyester, and vinyl ester) arranged longitudinally. A total of 75 kenaf fiber reinforced polymer composites containing up to 50% fiber volume fraction including 15 neat samples as control samples were produced. Then, the samples were tested using Universal Testing Machine to obtain their tensile behaviour. Results indicated that the composites’ performance increased gradually with every increment of fiber volume fraction. Factors affecting the tensile behaviour of kenaf fiber reinforced polymers are also explained and discussed. In conclusion, kenaf fiber can be used as reinforcing materials in polymeric materials.

Underside Shaped Concrete Block (USCB) is a groove shaped block on the underside surface. The USCB concept utilizes groove pattern to grip and produce better resistance to the underside surface of block units onto the bedding sand layer. However, the horizontal movement of block units is the major problem in pavement due to vehicle braking and accelerated action. This paper presents the laboratory evaluation on vertical and horizontal displacement of shell groove-USCB pavement laid onto different bedding sand layer thickness. The bedding sand layer thickness an essential parameter to produce better USCB’s performance. A series of laboratory scale test were conducted to study USCB type of the Shell-Rectangular 15 mm (Shell-R15) laid on three different loose bedding sand layer thicknesses of 50 mm,  70 mm and 90 mm respectively.  Then, push-in loading test and horizontal loading test were performed.    The result indicates, the bedding sand layer thickness has significant influence to the vertical and horizontal displacement to USCB Shell-R15 compared to control of 50 mm loose bedding sand layer thickness. The loose bedding sand layer thickness of 70 mm performed better compared to others.

This paper studies the effects of binder and filler composition to the strength properties of non-cement polyester grout (NCPG). The binder consisted of unsaturated polyester resin whereas the filler consisted of fine sand and fly ash. The composition of binder-to-filler ratios investigated were 0.43, 0.67, 1, 1.49, and 2.3. The mechanical properties of NCPG were investigated through flowability and compression tests. The test results show that the use of polyester resin combined with fine sand and fly ash produces good quality grout with high flowable rate, rapid setting, self-consolidating and high compressive strength.