Percentage Of Rice Husk Ash Research Articles

Performance of Rice Husk Ash - Calcium Carbide Waste in Concrete

This paper examines and present the findings of the physical and mechanical properties of concrete containing rice husk ash (RHA), and the blend of rice husk ash with calcium carbide waste (RHA-CCW). Concrete cubes, cylindrical and beam specimens containing different percentages of RHA and RHA-CCW by weight of cement (5, 10, 15 and 20 %) were cast. Compressive strength test was carried out after the specimens were cured in water for 7, 14, 28 and 56 days. Test for tensile and flexural strength was carried out after 28 days curing. Initial and final setting time test was carried out on mortar specimens with the same percentage of RHA and RHA-CCW. Bogues model was used to determine the elemental and compound composition of cement when blended with the RHA and RHA-CCW. From the results obtained, the compressive strength of RHA-CCW concrete increases as cement is partially replaced with RHA-CCW content, with the maximum strength attained at 5 % replacement. RHA concrete attains it maximum strength at 10 % replacement. The maximum compressive strength results obtained for both RHA and RHA-CCW concrete were higher than the strength of plain concrete (0 % replacement) by 1.1 % and 14.7 % respectively. Interestingly, results obtained for the tensile strength also shows a similar pattern of strength development with that of compressive strength. The flexural strength properties of concrete was improved upon when RHA-CCW was used in concrete compared to RHA. The results of setting time test for RHA mortar showed a decrease in setting time, while the reverse was the case for RHA-CCW mortar. In conclusion, provided adequate curing is maintained, the used of RHA-CCW gives a better performance in concrete than RHA. However, they both perform better in concrete than the plain, and can be used as additives in concrete production.

Utilization of Organic Waste and Inorganic Waste in Development of Green Hybrid Composite Material

Abstract Air pollution and soil pollution from organic and inorganic wastes are one of the major problems all over the world. Furthermore, disposal of these organic and inorganic wastes is very costly. In the present investigation, the organic waste considered is rice husk ash (RHA). Rice husk was collected from rice mill industries. The inorganic waste considered is fly ash. Fly ash was collected from thermal power plant industries. By utilizing these wastes in the development of composite materials, some environmental problems can be reduced. In this study, an attempt was made to develop AA6061 base composite material reinforced with different weight percentages of RHA and fly ash. Microstructure of RHA- and fly ash–reinforced composite shows proper distribution of reinforcements. Maximum tensile strength was found to be 145.5 MPa for AA6061 + 5 % RHA + 10 % fly ash composite. Minimum porosity and maximum hardness was found to be 0.80 % and 88 HRB, respectively, for AA6061 +7.5 wt% RHA + 7.5 wt% fly ash hybrid metal matrix composite. In the same way, minimum corrosion loss and minimum thermal expansion were 0.12 mg and 20 mm3 for AA6061 +7.5 wt% RHA + 7.5 wt% fly ash hybrid metal matrix composite, respectively. Minimum water absorption and minimum soil degradation was also found for AA6061 + 7.5 wt% RHA +7.5 wt% fly ash hybrid metal matrix composite. However, density of composites continuously decreases by increasing the percentage of RHA and fly ash in the development of composites.

Pozzolanic Reactivity and the Influence of Rice Husk Ash on Early-Age Autogenous Shrinkage of Concrete

In this study, the role of a locally available rice husk ash (RHA) in reducing early-age shrinkage of high performance concrete (HPC) after evaluating its pozzolanic reactivity was evaluated. The X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analyses were performed after burning rice husk to 700 and 950 oC. Presence of relatively high deposits of amorphous siliceous phases in RHA at 700 oC indicated its pozzolanic potential. Subsequently, this RHA was ground to desired fineness, followed by sieving through sieve No. 200. Eventually, the fine RHA was used as a substitute of cement in different percentages (10, 15 and 20%) to evaluate its influence in mitigating autogenous shrinkage in concrete. Prismatic concrete beams (100 mm x 100 mm x 800 mm) were cast to measure autogenous shrinkage along with cylinders (150 mm dia. x 300 mm height) to test compressive strength of concrete. The results indicated a slight increase in compression strength with addition of 10% RHA, which however, reversed and slightly reduced in concretes containing 15 and 20% RHA. Unlike strength results, the trend of autogenous shrinkage was rather uniform as the rate as well as the amount of early-age autogenous shrinkage continued to decrease with increasing percentage of RHA. Moreover, despite of reduced rate during first 24 hours, thereafter, the effect of 20% RHA on further reduction of autogenous shrinkage was insignificant and ended up only slightly lesser than the 15% RHA concrete at 7 days. Finally, the control cement sand mortar and mortar containing 15% RHA were cast to further validate the pozzolanic reactivity of RHA through scanning electron microscopy (SEM), EDX and thermogravimetric analysis (TGA) tests. An observation of reduced amount of calcium hydroxide (Ca(OH)2) in RHA mortar samples indicating its excellent pozzolanic potential when used as a partial substitute of cement in HPC.

Use of Rice Husk Ash as Strength-Enhancing Additive in Lightweight Cementitious Composite Mortars

This paper investigates the properties of rice husk ash (RHA) produced by using a ferro-cement furnace. The effect of RHA percentage on lightweight composite mortar consistency, initial and final setting time, plastic and dry set density, flexural and compressive strength were investigated. Incorporation of RHA in lightweight mortar increased water demand. The effect of early (7 and 14 days) and long term curing ages (90 and 120 days) on the mechanical strength properties of lightweight composite mortars with RHA were also analysed. Mortar samples show strength reduction of 10.6% and 8.57% compared to the control mix at early curing ages of 7 and 14 days, respectively. RHA mortar gave excellent improvement in strength for 20% replacement (18.85% and 21.69% increment compared to the control mix at long term curing of 90 and 120 days), and up to 25% of cement by weight be valuably replaced with RHA without adversely affecting the strength. Increasing replacement ratio of RHA enhanced the strength of blended mortar compared to low utilization ratio of RHA and control OPC mixtures.

Study on strength and durability characteristics of polypropylene fiber reinforced blended concrete tiles

Concrete is brittle and widely used as an artificial construction material with incorporation of cement, water and aggregate in necessary proportions. To overcome the brittle behavior of composites, fibers and admixture are added to the concrete. In this present investigation Polypropylene Fiber is added in varying percentage (0.2%, 0.4%, 0, 6%, 0.8% and 1%) to the weight of cement and constant percentage of Rice Husk Ash (15%) is replaced with cement. The polypropylene fiber reinforced blended concrete tiles of size 300mm x 300mm x 30mm are cast as per the code and tested at 28 days curing period. Flexural strength, Abrasion test, Dimensional quality and water absorption are studied. Among different proportion of Polypropylene Fiber Reinforced Blended Concrete, the best performance is achieved by the combination of 15% of Rice Husk Ash with 0.6% of Polypropylene Fiber.

Mechanical performance of self-compacting concrete incorporating rice husk ash

Self-compacting concrete (SCC) is a highly-workable concrete that fills the formwork under its own weight without needing vibration. The application of byproducts or waste materials as cement substitutes in SCC can enhance its mechanical performance. Rice husk ash (RHA) is one of the highly reactive byproducts. The pozzolanic performance of RHA due to high silica content makes it a suitable supplementary cementitious material for being used in SCC.In this paper, mechanical behavior of SCC was studied by 240 hardened concrete specimens with different variables i.e. partial replacement of cement with RHA (0%, 5%, 10%, 15% and 20%), concrete aged (3, 7, 28, 90, 180, and 270 days), and water to binder ratio (0.38, 0.44, 0.50, 0.56, 0.62, and 0.68). Fresh concrete properties were measured by V-funnel flow time, L-box, and slump flow diameter and time tests. Mechanical properties were determined in terms of compressive strength, modulus of elasticity, splitting tensile strength, and compressive stress-strain relationship tests. The test results showed that the workability of SCC containing RHA is decreased by increasing the RHA replacement ratio. On the contrary, compressive strength, modulus of elasticity, and splitting tensile strength increase with increasing the percentage of RHA up to 5% replacement.

Rice Husk Ash (RHA) Recycling in Brick Manufacture: Effects on Physical and Microstructural Properties

In this study RHA was used as silica source in the obtainment of clay bricks. Different compositions were prepared, substituting the clays with diverse percentages of RHA (0–20 wt%) and requested water contents. The pastes obtained were extruded in laboratory, dried and then fired in an industrial camera kiln. Technological tests were performed after drying (linear shrinkage and naphtha absorption) and firing [(24-h immersion) water absorption, linear shrinkage, weight loss, average flexural strength] steps. Besides, to analyze the effect on the microstructure and mineralogy, SEM/EDS and XRD analysis of the fired bricks were performed. From the tests conducted it is possible to note that RHA content contributes to reduce the linear shrinkage during drying while an opposite effect is observed for the water absorption. Regarding mechanical test, the products containing up to 5 wt% of RHA are in according to the recommended values for roof. Bricks containing higher amounts of RHA could be used in building manufacturing (light weighted faced load bearing walls) where moderate strengths and penetration protection (porosity/permeability) are required. The carbon unburned present in the RHA contributes to increase the final porosity and the weight loss of the bricks.

Study on concrete with rice husk ash

Rice husk ash (RHA) possesses high pozzolanic activities and very suitable as partial replacement of cement in concrete. This paper presents a comparative study on use of RHA as partial replacement of cement in concrete specimens. Review of the researches on physical, mechanical and structural properties of concrete containing RHA as partial replacement of ordinary Portland cement was included in this paper. Simultaneously, concrete specimens were tested with different percentages of RHA as replacement of cement content and with different w/c ratio. Compressive strength, flexural strength, tensile strength and slump test were carried out to evaluate the appropriateness of using RHA in concrete. The replacement of cement by RHA in structural concrete represents a good alternative in as economical as strength consideration of concrete, even without any kind of processing and found environmental benefits related to the disposal of waste. Review of researches shows that RHA-used concrete can resist chloride penetration more than normal ordinary Portland cement concrete.

Effect of residual rice husk ash on mechanical‐microstructural properties and thermal conductivity of sodium‐hydroxide‐activated bricks

This research compares the mechanical‐microstructural properties and thermal conductivity of the solid, green construction bricks that contain different percentages of sodium‐hydroxide‐activated residual rice husk ash and class‐F fly ash. The brick specimens were prepared following the guidelines of Vietnamese national standard in term of mixing, forming, and curing. Various percentages of rice husk ash (0%, 10%, 20%, 30%, 40%, and 50%) were added to a standard brick mixture in order to evaluate the influence of rice husk ash content on the strength development, void volume, water absorption capacity, bulk density, and thermal conductivity of the hardened bricks. Moreover, scanning electron microscopy was used to characterize surface morphologies of the brick samples. Further, the suitability of using a binder of rice husk ash and fly ash to produce alkali‐activated construction bricks was investigated. The bricks that were produced demonstrated generally good engineering performance and conformed to the relevant Vietnamese codes. Of particular note, the addition of rice husk ash influenced the properties of the bricks significantly, with brick strength peaking at a rice husk ash content of 10% and decreasing progressively at higher percentages. The findings from the present study support the efficacy of using a binder that contains rice husk ash and fly ash to produce green alkali‐activated construction bricks. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1647–1656, 2018

Fabrication and Performance Test of Aluminium Alloy-Rice Husk Ash Hybrid Metal Matrix Composite as Industrial and Construction Material

Aluminium matrix composites (AMCs) used extensively in various engineering fields due to their exceptional mechanical properties. In this present study, aluminium matrix composites (AMCs) such as aluminium alloy (A356) reinforced with rice husk ash particles (RHA) are made to explore the possibilities of reinforcing aluminium alloy. The stir casting method was applied to produce aluminium alloy (A356) reinforced with various amounts of (2%, 4%, and 6%) rice husk ash (RHA) particles. Physical treatment was carried out before the rice husk ash manufacturing process. The effect of mechanical strength of the fabricated hybrid composite was investigated. Therefore, impact test, tensile stress, compressive stress, and some other tests were carried out to analyse the mechanical properties. From the experimental results, it was found that maximum tensile, and compressive stress were found at 6% rice husk ash (RHA) and aluminium matrix composites (AMCs). In future, the optimum percentages of rice husk ash (RHA) to fabricate the hybrid composites will be determined. Also, simulation by finite element method (FEM) will be applied for further investigation.

Experimental Evaluation of Eco-friendly Light Weight Concrete with Optimal Level of Rice Husk Ash Replacement

Concrete is a versatile and cost-effective building material whose properties are influenced by age, curing condition, and installation. A number of studies deduced that there should be an association of benefits encouraged the use of partial replacements of cement seems to improve strength and durability properties of concrete. This paper presents a framework for feasibility assessment and determination of optimum percentage of rice husk ash (RHA) replacement. Five mix plans with RHA replacing ratio of 0-20% and constant micro- silica value by 10% were prepared. Tests results indicated that compressive strength increased by 20% with an increase in RHA up to 15%. The similar trend was observed in mix designs made of cement replaced by RHA up to 20% in water absorption coefficient measurement. Higher chloride ion penetration was observed in mix designs containing 25% RHA compared to that of conventional concrete. Mixes developed a slightly higher impact resistance than the control mix.

Soil stabilization with non-conventional eco-friendly agricultural waste materials: An experimental study

Abstract Highway construction and maintenance are usually expensive, and cost control efficiency is imperative. Although there are several stabilization methods, soil stabilization with agricultural waste materials, such as rice husk ash (RHA), is among the most eco-friendly and affordable methods. The aim of this study is to experimentally investigate the effects of adding RHA and ordinary Portland cement on the geotechnical properties of the clayey sand sampled from the Sejzi area, which lies east of the city of Isfahan, Iran. First, the oxide compounds of RHA, cement, and soil were determined using the X-ray fluorescence (XRF) test. Five different compounds of the soil with 2, 4, 6, and 8% of cement were mixed, and, later, different percentages of RHA (0, 2, 4, 6, and 8%) were added to determine the unconfined compressive strength (UCS), California bearing ratio (CBR), optimum moisture content (ω opt ), and maximum dry density (γ d ) of the stabilized soil compounds with 7, 14, and 28 curing days. The results showed that by increasing the content of RHA, the ω opt of the specimens increased, while the γ d decreased. The 28-day-cured specimen with 6% RHA and 8% cement showed the highest values of UCS and CBR at 25.44 and 18.2 times more than those of the values for untreated soil, respectively. The scanning electron micrograph (SEM) test of the aforementioned stabilized soil was characterized as a well-structured soil matrix with very small pores, which can be attributed to the pozzolanic reactions of the cement and RHA. The effectiveness, abundance, and the low cost of RHA will attract considerable environmental interest in this research.

Effect of waste rice husk ash on structural, thermal and run-off properties of clay roof tiles

Rice Husk Ash (RHA), a waste from firing process of clay products, has no proper usage. For this study, roof tile specimens were manufactured by replacing clay with different RHA percentages (i.e., 0%, 5%, 10%, 15% and 20%) in an industrial scale plant, so as to determine the effect of waste RHA from a brick firing process on structural, thermal properties and run-off qualities of clay roof tiles. For 10% replacement of clay with RHA, transverse breaking load was increased by 45.97% indicating higher ductility compared with that of the conventional tiles. Bulk density is reduced with the percentage of RHA added, promising a light-weight roof tile, a favourable tile for a roofing material. With increasing RHA content, water absorption increases. RHA replacement up to 15% is desirable, satisfying the water absorption limit according to standards. RHA replacement up to 20% doesn’t affect on the water penetration property. RHA mixed roof tiles can reduce the indoor temperature, feeling more comfortable for inhabitants. Collected runoff coming along the 10% RHA mixed clay roof tiles has a pH value of 7.22 and total solid concentration of 118.67mg/L, indicating RHA mixed roof clay tile will not cause any severe impact on the runoff. Hence this harvested runoff can still be utilized for non-potable activities while enhancing the strength and thermal properties of clay roof tiles.

Experimental Study on Rise Husk Ash & Fly Ash Based Geo-Polymer Concrete Using M-Sand

Serious environmental problems by means of increasing the production of Ordinary Portland cement (OPC), which is conventionally used as the primary binder to produce cement concrete. An attempt has been made to reduce the use of ordinary Portland cement in cement concrete. There is no standard mix design of geo-polymer concrete, an effort has been made to know the physical, chemical properties and optimum mix of geo-polymer concrete mix design. Concrete cubes of 100 x 100 x 100 mm were prepared and cured under steam curing for about 24 hours at temperature range of 40°C to 60°C. Fly ash is replaced partially with rice husk ash at percentage of 10%, 15% and 25%. Sodium hydroxide and sodium silicate are of used as alkaline activators with 5 Molar and 10 Molar NaOH solutions. Natural sand is replaced with manufacture sand. Test results were compared with controlled concrete mix of grade M30. The results shows that as the percentage of rice husk ash and water content increases, compressive strength will be decreases and as molarity of the alkaline solution increases, strength will be increases.

Compaction and swelling behavior of black cotton soil mixed with different non-cementitious materials

A series of compaction tests and one-dimensional swell tests were conducted to study the effect of addition of various percentages of rice husk ash, fly ash, and stone dust on compaction and swelling behaviour of black cotton soil. Specimens were prepared by adding 4, 8, 12, 16 and 20% by weight of various industrial waste materials to the black cotton soil. Standard proctor test was adopted to study the compaction behaviour of mix. For swelling behaviour one-dimensional swell test was performed by fixed ring consolidometer. Test results have shown that the optimum moisture content (OMC) increases due to addition of rice husk ash while maximum dry density (MDD) decreases. However, slight decrease due to the addition of fly ash and no significant change due to the addition of stoned dust in MDD have been observed. Decrease in the OMC was observed due to the addition of fly ash and stone dust. Swell potential and swell pressure of the soil decrease with the increase in percentage of additives. It is found from the swelling tests that all stabilizers can effectively suppress the heave and swelling pressure, but rice husk ash is more effective in suppressing the swelling behaviour.

Investigation of mechanical properties and electrical discharge machining of LM25-RHA metal matrix composite

In this work, the effect of weight percentage of rice husk ash (RHA) on mechanical properties and machinability of LM25 alloy of aluminium has been investigated. RHA has been mixed with the LM25 alloy by 4%, 6%, 8%, and 12% and aluminium metal composite (AMC) has been prepared by two-step stir casting process. The tensile strength, compressive strength, wear strength, hardness and optical microscopy examination have been done in order to characterise the AMC. Composite prepared. Further, the machinability has been investigated by conducting experiments on electrical discharge machining (EDM). The experiments have been conducted on Taguchi's L9 orthogonal array, the parameters being weight percentage (wt%), pulse current (Ip), pulse on time (Ton), and gap voltage (V) and the responses are material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra). The result reveals that the tensile, compressive, wear strength and hardness has increased sharply by increasing the reinforcing RHA. Further, Ip is significant parameter for MRR which shows an increasing trend with the pulse current, similar observation has seen with TWR, while Ra has increased by varying percentages of RHA from 4% to 12%. The microstructure examination through an optical microscope shows the uniform distribution of RHA into the base alloy with some casting defects.

Investigation of mechanical properties and electrical discharge machining of LM25-RHA metal matrix composite

In this work, the effect of weight percentage of rice husk ash (RHA) on mechanical properties and machinability of LM25 alloy of aluminium has been investigated. RHA has been mixed with the LM25 alloy by 4%, 6%, 8%, and 12% and aluminium metal composite (AMC) has been prepared by two-step stir casting process. The tensile strength, compressive strength, wear strength, hardness and optical microscopy examination have been done in order to characterise the AMC. Composite prepared. Further, the machinability has been investigated by conducting experiments on electrical discharge machining (EDM). The experiments have been conducted on Taguchi's L9 orthogonal array, the parameters being weight percentage (wt%), pulse current (Ip), pulse on time (Ton), and gap voltage (V) and the responses are material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra). The result reveals that the tensile, compressive, wear strength and hardness has increased sharply by increasing the reinforcing RHA. Further, Ip is significant parameter for MRR which shows an increasing trend with the pulse current, similar observation has seen with TWR, while Ra has increased by varying percentages of RHA from 4% to 12%. The microstructure examination through an optical microscope shows the uniform distribution of RHA into the base alloy with some casting defects.

Influence of Rice Husk Ash on the Properties of Concrete

This research was carried out to investigate various physical properties of Rice Husk Ash (RHA) and, some physical and mechanical properties of concrete incorporating RHA in different proportions. The concrete specimens were tested at 7, 21 and 28 days after curing. Test results revealed that the specific gravity of RHA was found lower than that of sand. The density of concrete containing RHA was recorded between 80-110 lb.ft-3, which is lower than conventional concrete. Water absorption was found increasing with the increase of RHA content in concrete specimens. There were significant variations in compressive strength values of concrete containing 5%, 10% and 20% volume of RHA. The compressive strength of 5% RHA specimen was 150-200% higher than that of other specimens. Hence, upto 5% replacement of RHA could be recommended for making normal lightweight concrete. The splitting tensile strength was about 9-10% of compressive strength. It was concluded that upto 5% RHA can be used effectively in making normal lightweight concrete. The higher percentage of RHA could be used in making non-structural concrete where the strength of concrete is not concerned.J. Environ. Sci. & Natural Resources, 9(1): 29-33 2016

The Influence of Rice Husk Ash Addition on the Properties of Metakaolin-Based Geopolymers

This paper investigates the replacement of metakaolin (MK) with rice husk ash (RHA) in the production of alkali-activated binders or geopolymers. The influence of the RHA addition on compressive and flexural strength, as well as water absorption and apparent porosity were determined, in terms of the percentage of RHA in the mixture and molar ratios of the mixes. Fourier Transform Infrared (FTIR) spectroscopy and Energy Dispersive spectroscopy (EDS) were carried out to assess the changes in the microstructure of the geopolymer matrices with the RHA addition. Results have shown that RHA may be a supplementary precursor for geopolymers. The composition of the geopolymer matrices containing 0-40% RHA is very similar, which indicates that the additional Si provided by RHA is not incorporated to the geopolymer matrix. In addition, geopolymers with RHA content higher than 40% present a plastic behavior, characterized by extremely low strength and high deformation, which can be attributed to the formation of silica gel in formulations containing variable Si/Al ratio.

Determination of Relationship between Dielectric Properties, Compressive Strength, and Age of Concrete with Rice Husk Ash Using Planar Coaxial Probe

Abstract This paper deals with an investigation of the dielectric properties of concretes that includes rice husk ash using a planar coaxial probe. The planar coaxial probe has a planar structure with a microstrip and coaxial features. The measurement was performed over the frequency range of 0.5-3.5 GHz, and concrete specimens with different percentages of rice husk ash were tested. The results indicated that the dielectric constant of the concretes was inversely proportional to the frequency, while the conductivity was proportional to the frequency. The dielectric constant decreased with the increasing age of the concrete at the frequency of 1 GHz. The conductivity of the concrete decreased with the increasing age of the concrete at the frequency of 3.2 GHz. In addition, the dielectric constant and the conductivity decreased when the compressive strength increased. It was also shown that the obtained dielectric properties of the concrete could be used to investigate the relationship between the compressive strength and age of the concrete. Moreover, there is an opportunity to apply the proposed probe to determine the dielectric properties of other materials.