Effect of pressing pressure on physical and mechanical properties of ELAEIS GUINEENSIS fronds composite board

Performance of composite boards usually depends on the raw materials selection and fabrication parameters. This paper presents the effect of different level of applied pressure towards the performance of the end product of Elaeis guineensis composite board. The OPF was collected from a private plantation in Sarawak and refined into smaller particles by using a crusher machine. Sieved OPF particles that retained on the 0.60mm sieve mesh were used to fabricate composite boards with a targeted density of 0.7g/cm3. The 20 cm × 20 cm × 0.50 cm composite boards were fabricated under same hot press temperature of 160℃ for three different applied pressures of 5MPa, 6MPa, and 7MPa respectively. The physical and mechanical properties test were conducted according to the Japanese Industrial Standard (JIS A5908:2003). It is indicated from the results that the performance of Elaeis guineensis composite board improved with increasing applied pressure. The composite boards satisfied the provision set for the internal bond (IB) strength and modulus of rupture (MOR) in JIS A5908:2003. Unfortunately, the thickness swelling percentage exceeded the maximum set value. Overall performance investigated that Elaeis guineensis composite board is suitable to be used in indoor applications such as based materials, decorative boards, and teaching aids

Investigation on the properties of acrylic emulsion polymer based ordinary portland cement concrete reinforced with hooked steel fiber

Polymer modified cement-based materials and fiber reinforced cementitious composites are both widely used in civil engineering applications. Both show great advantages, especially in repair and rehabilitation. The work reported here, however, deals with polymer modified fiber reinforced cement based composites (PM-FRC) that is, combined used of fibers and polymers in the same system. This paper reports the quantitative study of all the three additives each taken with three settings, namely, steel fiber (1.0%, 1.5% and 2.0%), acrylic emulsion polymer (1.0%, 2.5% and 4.0%) and silica fume (5.0%, 6.0% and 8.0%). The other two control variables were chosen as water-cement ratio (0.42, 0.50 and 0.60) and aging (3, 7 and 28 days). In this study, steel fiber reinforced polymer modified concrete (SFRPMC) was produced with the addition of acrylic emulsion polymer (<4%) into steel fiber reinforced concrete which enhance the workability, strength and thermal properties. The unique properties of steel fiber qualify it to be the best option as reinforcement in acrylic polymer cement composite. However, uniform dispersion is the biggest challenge in generating a composite with an optimum performance. Hence, acrylic emulsion polymer and silica fume with different percentages was used to improve the quality of steel fiber reinforced concrete. In this study, we have used a comprehensive approach known as Design of Experimental (DoE) which had been applied efficiently from the material formulation and processing stage until the material characterization. Through verification experiment, the compressive strength had increased by as much as 59% compared to control concrete specimen. To optimize other mechanical properties such as flexural strength, splitting tensile strength and modulus of elasticity, the L9 array method was used. Variant analysis and average analysis were then used to get the optimum formulation and through the X-ray diffraction analysis, the dispersion of acrylic polymer is slightly improved when combined with steel fiber reinforced concrete. From morphology observation, the dispersion of steel fiber with acrylic polymer addition showed a better uniformed dispersion in SFRPMC. Through thermal analysis, optimum specimen was proven to own good thermal stability than the other specimens. Steel fiber reinforced acrylic emulsion polymer modified concrete (SFRPMC) were produced based on the significant parameters suggested by Taguchi Analysis that was performed earlier. SFRPMC had improved the dispersion of steel fiber and acrylic polymer in matrix composite due to the presence of a few functional groups of elements from different materials, as observed through the morphology examination through SEMEDX analysis. Synergistic effect between the fibers and the polymer were observed in most of the composites as long as suitable polymer dosages were used. It is concluded that a high performance composites with 2.5% acrylic emulsion polymer, 8% silica fume, 1.5% steel fiber and water-cement ratio 0.50 at 28 days curing could be a promising material for both structural and repair purpose

Properties of Concrete Containing Foamed Concrete Block Waste as Fine Aggregate Replacement

Environmental degradation due to excessive sand mining dumping at certain places and disposal of foamed concrete block waste from lightweight concrete producing industry are issues that should be resolved for a better and cleaner environment of the community. Thus, the main intention of this study is to investigate the potential of foamed concrete block waste as partial sand replacement in concrete production. The foamed concrete waste (FCW) used in this research that were supplied by a local lightweight concrete producing industry. The workability and compressive strength of concrete containing various percentage of foamed concrete waste as partial sand replacement has been investigated. Prior to the use, the foamed concrete waste were crushed to produce finer particles. Six concrete mixes containing various content of crushed foamed concrete waste that are 0%, 10%, 20%, 30%, 40% and 50% were used in this experimental work. Then the prepared specimens were placed in water curing until the testing age. Compressive strength test and flexural strength tests were conducted at 7, 14 and 28 days. The result shows that integration of crushed foamed concrete waste as partial sand replacement in concrete reduces the mix workability. It is interesting to note that both compressive strength and flexural strength of concrete improves when 30% crushed foamed concrete waste is added as partial sand replacement

Microstructural aspects in steel fiber reinforced acrylic emulsion polymer modified concrete

Scanning electron microscope observations of polymer-free and polymer-modified cements have shown that the polymer particles are partitioned between the inside of hydrates and the surface of anhydrous cement grains. For optimum dosage of acrylic emulsion polymer with 2.5%, the C-S-H gel in this structure is finer and more acicular. Some polymer adheres or deposit on the surface of the C-S-H gel. The presence of acrylic emulsion polymer confines the ionic diffusion so that the Ca(OH)2 crystallized locally to form fine crystals. The void in the structures seems to be smaller but no polymer films appears to be bridging the walls of pores although many polymer bonds or C-S-H spread into the pore spaces. In addition to porosity reduction, acrylic emulsion polymer modified the hydration products in the steel fiber –matrix ITZ. The hydration product C-S-H appeared as a needle like shape. The needle-shaped C-S-H increases and gradually formed the gel, with needles growing into the pore space. The phenomenon is more obvious as curing age increased

Microstructural aspects in steel fiber reinforced acrylic emulsion polymer modified concrete

Scanning electron microscope observations of polymer-free and polymer-modified cements have shown that the polymer particles are partitioned between the inside of hydrates and the surface of anhydrous cement grains. For optimum dosage of acrylic emulsion polymer with 2.5%, the C-S-H gel in this structure is finer and more acicular. Some polymer adheres or deposit on the surface of the C-S-H gel. The presence of acrylic emulsion polymer confines the ionic diffusion so that the Ca(OH)2 crystallized locally to form fine crystals. The void in the structures seems to be smaller but no polymer films appears to be bridging the walls of pores although many polymer bonds or C-S-H spread into the pore spaces. In addition to porosity reduction, acrylic emulsion polymer modified the hydration products in the steel fiber –matrix ITZ. The hydration product C-S-H appeared as a needle like shape. The needle-shaped C-S-H increases and gradually formed the gel, with needles growing into the pore space. The phenomenon is more obvious as curing age increased

Engineering Behavior of Concrete with Recycled Aggregate

Concrete is extensively used as construction materials in Malaysia. Concrete contributes suitable feature for construction industry for instance durability, adequate compressive strength, fire resistance, availability and is economic as compared to other construction materials. Depletion of natural resources and disposal of construction and demolition waste remarkably claim environmental threat. In this paper, the engineering behavior, durability, and concrete microstructure of recycled concrete aggregates (RCA) on short-term concrete properties were investigated. The studied concrete at design mix proportion of 1:0.55:2.14:2.61 (weight of cement :coarse aggregates :sand :water) used to obtain medium-high compressive strength with 20%, 50%, and 100% of RCA. Results show that for the same water/cement ratio, RCA replacement up to 50% still achieved the targeted compressive strength of 25 MPa at 28 curing days. Addition, at similar RCA replacement, the highest carbonation depth value was found at 1.03 mm which could be attributed to the pozzolanic reaction, thus led to lower carbonation resistance. Scanning electron microscopy microstructure shows that the RCA surface was porous and covered with loose particles. Moreover, the interfacial transition zone was composed of numerous small pores, micro cracks, and fissures that surround the mortar matrix. On the basis of the obtained results, recommendable mineral admixtures of RCA are necessary to enhance the quality of concrete construction

Effect of fiber loading on the flexural and tensile strength of oil palm frond fiber reinforced polymer composite

Research on composite have been widely done throughout the world. Incorporation of reinforcing materials into matrix can one day replace the use of conventional materials such as polymers, metals, ceramics and woods. In this research, a composite made of oil palm frond fiber and urea formaldehyde is fabricated. As oil palm frond fiber can be obtained in great amount due to high amount of wastage generated, composite can be a way to reduce this wastage. There are two different type of fiber loading which is 40% and 50%. The fiber and UF are mix until it is homogenous. It is then placed into the hot press machine to undergo hot press process. After the fabrication, the mechanical properties of the composite will be tested and observed. The mechanical test includes flexural and tensile test. Both tests are done in accordance to the ASTM standard which are ASTM D-790 and ASTM D-638. The morphological characteristic of the composite will also be observed in this study. The results show that the composite with higher fiber loading, which is 50 %, have better mechanical properties. The composite with 50 % of fiber has a flexural strength of 1.4306 MPa, a modulus of elasticity of 1248.9516 MPa and a tensile strength of 3.874 MPa. These composites can be used as an alternative for wood and automotive application

Engineering Behavior of Concrete with Recycled Aggregate

Concrete is extensively used as construction materials in Malaysia. Concrete contributes suitable feature for construction industry for instance durability, adequate compressive strength, fire resistance, availability and is economic as compared to other construction materials. Depletion of natural resources and disposal of construction and demolition waste remarkably claim environmental threat. In this paper, the engineering behavior, durability, and concrete microstructure of recycled concrete aggregates (RCA) on short-term concrete properties were investigated. The studied concrete at design mix proportion of 1:0.55:2.14:2.61 (weight of cement :coarse aggregates :sand :water) used to obtain medium-high compressive strength with 20%, 50%, and 100% of RCA. Results show that for the same water/cement ratio, RCA replacement up to 50% still achieved the targeted compressive strength of 25 MPa at 28 curing days. Addition, at similar RCA replacement, the highest carbonation depth value was found at 1.03 mm which could be attributed to the pozzolanic reaction, thus led to lower carbonation resistance. Scanning electron microscopy microstructure shows that the RCA surface was porous and covered with loose particles. Moreover, the interfacial transition zone was composed of numerous small pores, micro cracks, and fissures that surround the mortar matrix. On the basis of the obtained results, recommendable mineral admixtures of RCA are necessary to enhance the quality of concrete construction