Papers by Keyword: Workability

Abstract: Steel industry generate various kind of industrial waste, by-product after extracting final product as steel, depends on different types of ore refining methods. This research aims to identify experimentally, sustainable building material solution from waste to ingest in construction field centered on previous effort and literatures. EAF (Electric arc furnace) slag, a kind ofwaste material has an excellent potential to replace the natural coarse aggregate in concrete. The evaluation of the physical, chemical & microstructure properties of EAF slag as aggregate shows reasonably enhanced results. The M-50 grade of concrete was designed with various EAF slag replaced (0, 25, 50, 72, 100%) in place of natural coarse aggregate. It is observed thatfresh and hardened concretewith 50% EAF slag replacement exhibits outstanding performance over conventional concrete.

Abstract: The improvement of mixture quality has been the priority of the modern-day construction industry while reducing the financial implications of the final product. This investigation concentrated on the application of glass as fine aggregate in the production of concrete. The fine aggregates used were partially substituted with fine glass. The replacement was done at (0, 10, 20, 30, 40, and 50%) by weight of fine aggregates, with other materials constant. A concrete mixture was prepared and the slump flow test and density were examined. The concrete specimens were produced, cured, and compressive, flexural, and splitting tensile intensity tested at 7, 14, and 28 durations. The workability and density of concrete reduce as the percentage replacement increases and the maximum reduction are (25 and 6.5%) respectively for (50%) glass aggregate replacement. The highest development in concrete compressive strength, flexural and splitting tensile intensity is (16.4, 14.7, and 15.1%) for 28 days of the glass aggregate percentage (20%) and the highest decrease is (3.4, 3.1, and 3.6%) for the percentage (50%).

Abstract: The effects of gravel’s geometry and cement content are one of the most important parameters in the construction industry. Two types of aggregates, sharp corners and rounded corners with different sizes, and several samples of various cement contents were prepared. Then the workability, strength, and elastic modulus tests were performed. Experimental results indicate that workability and compressive strength increase with increasing cement content as expected (12% and 22% for workability and 64% and 69% for compressive strength with regard to sharp and rounded aggregate, respectively). Also, in most cases, seismic parameters improve too (maximum of 120% and 107% for energy absorption regarding sharp and rounded aggregate, respectively). The results demonstrate that concrete samples with the largest grain size of 12.5 mm have the most compressive strength, elastic modulus, energy absorption, and ductility in comparison with other samples (maximum 24% and 18% for elastic modulus with reference to sharp and rounded aggregate, respectively). Finally, the results show that the sharp corner aggregates have greater strength and better seismic parameters in comparison with rounded corner (maximum 16% for energy absorption). In contradiction to the above statement, the rounded corners aggregates have more workability than sharp corner ones (up to 18%), and also the workability increases by reducing the gravel size (26% and 19% for sharp and rounded aggregate, respectively). A statistical approach was used to determine the optimal shape and size of aggregate and organize the results scattering.

Abstract: Palm oil fuel ash (POFA) and palm oil clinker (POC) are by-products from palm oil mill which disposed as environmental polluting wastes. Excessive sand mining activity by sand traders for the widely used concrete production, harms the river’s ecosystem. Success in discovering alternative material that can function as partial sand replacement for concrete production would reduce the dependency on natural sand supply. This research investigates the effect of POFA as a partial fine aggregate substitute on the workability and compressive strength of palm oil clinker lightweight aggregate concrete. Five mixes have been prepared by integrating diverse percentage of POFA ranging from 0, 5, 10, 15 and 20 as fine aggregate substitute by weight of sand. Then, concrete mixes were subjected to slump test and compressive strength test. The outcomes have shown the combination of 5% POFA in this lightweight aggregate concrete produces concrete with the targeted strength and has the potential to be used for structural application. Utilization of POFA in concrete would save the consumption of river sand and contribute to sustainable environment.

Abstract: The widespread use of natural sand mined from the river for concrete production worldwide causes environmental degradation. The cockle shell waste from aquaculture industry which discarded at dumpsite also pollutes the environment. Utilization of cockle shell as partial sand replacement in concrete would reduce the harvesting of sand from the river and limit the waste dumping from cockle industry. The experimental research investigates the effect of different sizes crushed cockle shell (600µm and 2.36mm) as partial sand replacement on the workability and compressive strength of lightweight aggregate concrete. 5 types of concrete mixes consisting various percentages of crushed cockle shell ranging from 0%, 5%, 10%, 15% and 20% were used in this research. All specimens were water cured until the scheduled testing time. The workability and compressive strength of concrete were determined via slump test and compressive strength test respectively. The outcome shows that the use of different sized crushed cockle shell as partial sand replacement influences the workability and strength of concrete. The concrete becomes more workable when larger quantity of crushed cockle shell is used. Integration 5% of 600µm and 10% of 2.36mm crushed cockle shell forms concrete with the targeted strength. Using crushed cockle shell as mixing ingredient in concrete reduces quantity of waste thrown and contributes to cleaner surrounding.

Abstract: As time goes on, the usage of natural resources for concrete production affects the environment. Both the quarrying activities for granite aggregate harvesting and sand mining destroys the environment. At the same time, industrial by-products namely palm oil clinker (POC) and spent garnet waste which thrown as waste, also cause pollution. The inclusion of spent garnet waste as fine aggregate replacement in POC lightweight aggregate concrete production would reduce the consumption of river sand. This research investigates the effect of using spent garnet waste as a fine aggregate replacement on workability, dry density, and compressive strength of POC lightweight aggregate concrete. Five concrete mixes were prepared by varying the percentage of spent garnet waste as a fine aggregate replacement up to 40% by the weight of fine aggregate. All concrete specimens underwent water curing until the testing age of 7 and 28 days. The specimens were tested to determine dry density and compressive strength. Overall, the use of spent garnet as partial fine aggregate replacement influences the concrete properties. Inclusion of 20% spent garnet in concrete resulted in formation of semi-lightweight concrete with density of 2240 kg/m³. On top of that, the concrete with spent garnet exhibit higher compressive strength of about 60MPa which is about 14% higher than control specimen. Conclusively, the utilization of spent garnet as a partial fine aggregate replacement would save river sand consumption and reduce the dumping of spent garnet.

Abstract: Solid waste management is one of the challenging issues faced by the developing countries. The developing countries find it very critical to manage the disposal of waste generation. India ranks 3^rd in the production of egg, generating about 3.8 billion kilograms annually. This growth in the production of larger rate is mainly due to the hike in domestic consumption. This could lead to larger generation of solid waste. To overcome these issues, eggshell could be effective incorporated into concrete production as cementitious blends. This paper investigates the suitability of eggshell powder as partial substitute to cement. The material characterization techniques such as SEM were used to investigate the feasibility of using eggshell powder. The study was conducted by producing cement mortars in the ratio of 1:3 parts of cement. Then the cement was partially replaced by eggshell powder at 5%, 10%, 15%, 20% by its weight. The fresh property was assessed using the flow table test, while the hardened property was determined using the compressive strength of the cement mortar at 7, and 28 days. From the test results, 10% eggshell powder when utilized in mortar gives optimum compressive strength.

Abstract: Recently developed geopolymer concrete is considered a promising alternative for ordinary Portland cement (OPC) concrete. It accounts for green and durable civil infrastructure because the geopolymer concrete is made of industrial by-products and an alkali activator. This paper presents the investigation of a geopolymer mixture (paste) made of a combination of off-ASTM fly ash (FA) and ground granulated blast furnace slag (GGBFS) produced in a steel-making plant, Kazakhstan. The effect of water/binder ratios (w/b=0.32 and 0.35), alkaline activator solution/binder ratios (AAS/b=0.20 and 0.40), and GGBFS/fly ash ratio (S/FA=50/50 and 25/75) on geopolymer concrete’s properties were evaluated. These include workability, compressive strength, and drying shrinkage. The test results showed that increasing water content increases compressive strength and drying shrinkage of the geopolymer specimen. Decreasing alkaline content resulted in a drop in compressive strength and workability but positively minimized drying shrinkage. The mixture containing 50% GGBFS and 50% FA tends to have higher strength than the GGBFS/FA ratio of 25/75.

Abstract: Concrete is very strong in compression but weak in tension. It is therefore reinforced with steel reinforcement to carry the tensile stresses. The use of steel reinforcement in concrete is expensive, and calls for investigation on other materials that are cheap in order to reduce the cost. Due to these reasons, a study has been made with the objective of determining the suitability of areca palm fibers in reinforcing concrete for improving its properties at fresh and hardened states. The sampled areca palm fibers were treated by using 5% by weight of NaOH solution. Experiments were conducted on concrete grade C25 with addition of fibers in five mix proportions of 0.1%, 0.3%, 0.5%, 0.7% and 0.9% by weight of cement. The results showed that the workability of concrete with fibers is lesser than that of conventional concrete. Also, the modulus of elasticity and compressive strength increased to an optimum weight fraction of 0.7% beyond which they started to decrease. The ability to resist cracking and spalling were also enhanced. The study found that the optimum fibers content was 0.7% by the weight of the cement and that areca palm fibers can be used to improve the engineering properties of concrete. Keywords: Areca fibers, concrete, workability, compressive strength, tensile strength, modulus of elasticity

Abstract: In the civil engineering field, the incorporation of chemical admixtures is now a practical technics' used for improving the properties of concrete, such as improved workability, decreasing the water demand, increasing strength, etc. However, chemical admixtures have some disadvantages such as environmental pollution during both their manufacture and their use, else, there are rare somewhere. Because of this background, bio-admixtures appear principally useful, due to their environmental effect and friendly properties, bio-admixtures are substances obtained from a biodegradable product also resulting from the methanisation. The objective of this research is the valorization of household waste used as a bio-admixture. Moreover studying its effect on cement path workability, start/end of the cement setting.