Abdul Rahman Mohd Sam

A Review of Structural Performance of Oil Palm Empty Fruit Bunch Fiber in Polymer Composites

According to environmental concerns and financial problems, natural fibers have become interesting and fascinating nowadays to be used as an industrial material and structural material for rehabilitating of structures. Oil palm empty fruit bunch fiber (OPF) is a natural fiber which is found a lot in tropical areas. Scientists have used OPF fiber with many types of resins such as epoxy, polypropylene, polyester, and phenol formaldehyde. Therefore, this paper focused on the properties of OPF fiber and gathered mechanical properties of OPF composites (OPF as reinforcement of polymer) reported by other researchers in terms of tensile and flexural properties. Furthermore, the chemical surface modification methods to solve the interfacial bonding of fiber and polymer were mentioned. In addition, the results of hybrid composites of OPF were also discussed in this paper. Meanwhile, the results of composites were compared to pure resin properties and also the stress-strain diagram and internal strain energy of composites were considered. Besides, the effects of adding OPF to other composites to make a new hybrid composite were indicated. Finally, it is clear that the use of oil palm fiber composites for structural elements for bearing loads is not recommended but the usage of OPF composites for secondary structural elements may be recommended due to future researches.

Seismic Performance of RC Beam-Column Connections with Continuous Rectangular Spiral Transverse Reinforcements for Low Ductility Classes

The seismic performance of RC columns could be significantly improved by continuous spiral reinforcement as a result of its adequate ductility and energy dissipation capacity. Due to post-earthquake brittle failure observations in beam-column connections, the seismic behaviour of such connections could greatly be improved by simultaneous application of this method in both beams and columns. In this study, a new proposed detail for beam to column connection introduced as “twisted opposing rectangular spiral” was experimentally and numerically investigated and its seismic performance was compared against normal rectangular spiral and conventional shear reinforcement systems. In this study, three full scale beam to column connections were first designed in conformance with Eurocode (EC2-04) for low ductility class connections and then tested by quasistatic cyclic loading recommended by ACI Building Code (ACI 318-02). Next, the experimental results were validated by numerical methods. Finally, the results revealed that the new proposed connection could improve the ultimate lateral resistance, ductility, and energy dissipation capacity.

Evaluation of new spiral shear reinforcement pattern for reinforced concrete joints subjected to cyclic loading

Using continuous spiral reinforcements can greatly improve the seismic performance of reinforced concrete columns, in terms of ductility and energy dissipation capacity. The simultaneous incorporation of this method in beams and columns might influence the behaviour of beam–column connections as wide spectrums of brittle failure were observed in this region. A new proposed beam–column connection introduced as ‘twisted opposing rectangular spiral’ was investigated in this research in both experimental and numerical manners along with comparing its seismic performance with both normal rectangular spiral and conventional shear reinforcement systems. The design of three full-scale beam–column connections was performed according to Eurocode (EC8-04) for high ductility classes, and the quasi-static cyclic loading recommended by American Concrete Institute Building Code (ACI 318-08) was hired to conduct the seismic tests. Finally, the experimental results were validated by numerical results obtained from the finite element analysis of the three specimens. The results revealed improved ultimate lateral resistant, energy dissipation capacity and ductility for the new proposed connection.

Flexural Behavior of GFRP RC Beam Strengthened with Carbon Fiber Reinforced Polymer (CFRP) Plate: Cracking Behavior

There has been much research conducted on the current performance of Fiber Reinforced Polymer (FRP) as reinforcement. It was due to FRP easier to maintain than steel during construction because of less weight. Laboratory works on the flexural behavior of concrete beams that with GFRP and CFRP use as a plate strengthening for the beam size 2800 x 200 x 250 millimeter. study of the pattern of cracking and failure modes of the beam will be compared between the ten types of beams consisting of steel reinforced beams , beam-reinforced GFRP and GFRP reinforced beams strengthened with CFRP with different lengths. Comparing between the beam bending performance was examined through the ultimate load, cracking and failure modes.

Performance of Iron Ore Tailings as Partial Replacement for Sand in Concrete

This paper reports preliminary findings on the properties of concrete produced using iron ore tailings obtained from ZCM Minerals SDN BHD located in Kotta Tingi, Johor, Malaysia. The Iron Ore Tailings (IOT’s) a waste product, with particle size range from (850μm - 75μm) obtained from Iron Ore Processing was utilized as fine aggregate to produce concrete. Based on British Standard (BS) guidelines, normal concrete mix was designed. Five types of concrete samples (C0, C1, C2, C3, and C4) were produced, with the percentage of tailings used to replace sand as fine aggregate ranging from 0 to 40[%]. The reference sample is C0 with no tailings and the four others, containing tailings at 10[%] intervals. The effect of iron ore tailings on the consistency of the fresh concrete were studied, as well as the density, compressive strength, flexural strength and splitting tensile strength, of the hardened concrete. The results of the consistency tests on concrete shows that the slump values ranges from 81 to 53[mm] from concrete sample C0 to C4 respectively, while the compacting factor values ranges from 0.92 to 0.89 respectively. The density of the produced concrete cube samples falls within the range 2350 to 2430[kg/m3]. The concrete sample C3 gave the highest compressive strength value of 43.70[N/mm2]. The concrete sample C3 also gave the highest flexural strength value of 4.79[N/mm2], while the The concrete sample C4 gave the highest splitting tensile strength value of 4.0[N/mm2] after curing period of 28[days].

Properties of binary and ternary blended cement mortars containing palm oil fuel ash and metakaolin

Abstract This paper has investigated the properties of mortars made from binary and ternary blends of metakaolin (MK), palm oil fuel ash (POFA), and ordinary Portland cement (OPC). A total of 17 different mortar mixtures were produced. The OPC in the mixtures was partially replaced by MK, POFA, or a combination of MK and POFA at different replacement levels of (0–30%) by weight of the binder. At the fresh state, the flow (workability) of mortar mixtures was determined, while at the hardened state, the compressive strength and porosity at the ages of 7, 28, and 90 days were evaluated. The results showed that the flow of mortar is boosted with the combined use of MK and POFA compared to when MK is separately used. Besides, improvement in low early compressive strength development and reduction in high porosity from use of POFA occurred with the addition of up to 10% MK content. Therefore, the combination of POFA and MK could be used as a supplementary cementitious material to produce cement-based material of higher quality than OPC.

Behavior of Palm Oil Fuel Ash and Metakaolin Ternary Blend Cement Mortar at Elevated Temperatures

This study examines the effect of a ternary blend of palm oil fuel ash (POFA) and metakaolin (MK) on the behavior of cement mortar exposed to elevated temperatures. The ternary blend was produced by combining 10% POFA and 10% MK by weight as a substitute to cement. Three additional samples which include plain portland cement (OPC), 20% MK binary and 20% POFA binary were also produced for comparison. Compressive strengths and ultrasonic pulse velocities of the mortar samples after heating to temperatures of 200, 400, 600, and 800°C for 2 h were assessed. Furthermore, X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy analysis were carried out to examine the microstructure of the samples. The results show that the compressive strength and microstructure of mortar exposed to elevated temperatures improved with the simultaneous use of POFA and MK compared to plain OPC mortar and when POFA or MK is singly used. The ternary blend of cement/POFA/MK can, therefore, be used as a fire resistant material.

The Mechanical Properties of Steel-Polypropylene Fibre Composites Concrete (HyFRCC)

This paper discusses the experimental results on the mechanical properties of hybrid fibre reinforced composite concrete (HyFRCC) containing different proportions of steel fibre (SF) and polypropylene fibre (PPF). The mechanical properties include compressive strength, tensile strength, and flexural strength. SF is known to enhance the flexural and tensile strengths, and at the same time is able to resist the formation of macro cracking. Meanwhile, PPF contributes to the tensile strain capacity and compressive strength, and also delay the formation of micro cracks. Hooked-end deformed type SF fibre with 60 mm length and fibrillated virgin type PPF fibre with 19 mm length are used in this study. Meanwhile, the concrete strength is maintained for grade C30. The percentage proportion of SF-PPF fibres are varied in the range of 100-0%, 75-25%, 50-50%, 25-75% and 0-100% of which the total fibre volume fraction (Vf) is fixed at 0.5%. The experimental results reveal that the percentage proportion of SF-PPF fibres with 75-25% produced the maximum performance of flexural strength, tensile strength and flexural toughness. Meanwhile, the percentage proportion of SF-PPF fibres with 100-0% contributes to the improvement of the compressive strength compared to that of plain concrete.