Impact of the Properties and Reactivity of Rice Husk Ash on Lime Mortar Properties (original) (raw)
Related papers
Study of the Mechanical Behaviour of Mortars Modified with Rice Husk Ash
Journal of Minerals and Materials Characterization and Engineering
The purpose of this work is to study the influence of Rice Husk Ash (RHA) on the mechanical strength of mortars. For this purpose, ash was produced by calcining rice husk at 680˚C for 5 hours to produce reactive pozzolan. The chemical and mineralogical composition studied by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and X-Ray Diffraction (XRD) showed that this ash is rich in amorphous silica. The ash presents a good pozzolanic activity with a lime fixation rate of 100% after only 7 days of treatment. The addition of RHA to cement contributes to the formation of calcium silicate hydrate (CSH) and calcium aluminate hydrate of C 3 ASH 6 type. The presence of RHA in the mortars improves their mechanical strength. This improvement is due to the filler effect of RHA and to formation of the CSH resulting from the pozzolanic reactivity between the amorphous silica of the RHA and the portlandite released by hydration of the cement.
Advanced Materials Research, 2012
The properties of mortar containing rice husk ash at varying temperatures were studied. Three rice husk ash samples were prepared at different temperatures and with various colors, i.e., 600°C (pink), 800°C (grey), and 1000°C (white), all were used for this study. Ordinary Portland cement (OPC), a well known universal binder, was partially replaced with rice husk ash at 10, 15, 20, and 30% by weight of binder. The water to binder ratio (W/B) of the mortar was kept constant at 0.45. The mortars were subjected to seawater or saturated Ca(OH) 2 solution. The controlled and exposed mortars were characterized using X-ray diffraction, FTIR spectroscopy and compressive strength test. The results show that the amount of silica present in RHA are varied with burning temperature and colors, approximately in the range of 95 to 97%. White RHA produced higher compressive strength both in seawater and Ca(OH) 2 solution. Finally, white RHA with 15% replacement was most suitable to be used as additive in OPC, and showed good potential for use in seawater applications and alkaline environment.
Lime mortars with rice husk ash for ancient masonry
This paper presents some preliminary results achieved in the aim of a research program with the main objective of evaluating the potential interest of using rice husk ashes on aerial lime based mortars for old buildings. The mechanical and physical characteristics and potential durability of lime mortars formulated with commercial rice husk ashes are analysed and their behaviour compared with a pure lime mortar. The results are also analysed taking into account the main aspects that are responsible for the compatibility between the new mortars and the original building materials. The potential durability of the tested mortars is evaluated through salt crystallization tests performed with sodium chloride and sodium sulphate solutions. The improvement of some properties of the lime mortars due to the presence of rice husk ashes pointed out the interest of the research in this domain, namely in what concerns the design of mortars with a moderately hydraulic behaviour for old buildings.
2013
The effect of calcination temperature of rice husk on the properties of rice husk ash (RHA) and RHA mortar was investigated. The rice husk was prepared using the water beneficiation method and calcined at temperatures of 400oC, 500oC, 600oC, 700oC and 800oC respectively. X-Ray Defractograph (XRD) and X-Ray Florescence (XRF) analysis were carried out on the RHA to determine its degree of amorphosity and the effect of calcination on its silica content respectively. The Ordinary Portland cement (OPC) was replaced with 15% RHA and the mortar tested for setting time, pozzolanic activity index (PAI) and compressive strength. The result of XRD analysis revealed that RHA at 500oC had broadest peak at 2Ө value of 22.141 degrees and lowest intensity at 2Ө value of 20.8 degrees when compared to that at 400oC, 600oC, 700oC and 800oC respectively. The number of crystalline peaks of intensity greater than 160 was also lowest for RHA at 500oC indicating high amorphous silica content. The result of XRF analysis showed that RHA calcined at any temperature between 400oC and 800oC contain more than 70% SiO¬2¬ as stipulated by ASTM C 618. The pozzolanic activity index for mortar incorporating RHA calcined at 400oC, 500oC, 600oC, 700oC and 800oC were determined but only that for RHA calcined at 500oC (86.5 and 101.2 at 7 and 28 days respectively) met the specification of ASTM C 618-03 (75% min) for a class C pozzolana. The average compressive strength at 28 days curing for RHA mortar at 400oC, 500oC, 600oC, 700oC and 800oC calcination were 8.3 N/mm2, 17.1N/mm2, 9.6N/mm2, 6.9N/mm2 and 5.6 N/mm2 respectively. However, its only mortar incorporating RHA calcined at 500oC meeting the requirement of ASTM 270 for a class S mortar (12.41 N/mm2 minimum). Thus, RHA calcined at 500oC is recommended for use at 15% replacement as a cement substitute in mortar.
Analysis of Microstructural Behaviour of Rice Husk Ash Blended Cement Mortar
IRJET, 2023
The stated work investigates the microstructural properties of Rice Husk Ash and the viability of replacing cement with it. Cement was replaced by Rice Husk Ash (0-25 percent at 5% intervals) to investigate its impact on cement mortar's mechanical and physical characteristics, including the evaluation of the microstructure. Samples used were tested after 3, 7, and 28 days of curing. It was noted that when a sample has a consistent water content, it produces a dry mix when more than 10% of the cement was replaced by RHA. owing to dry mix the mortars attempt to hydrate itself was unsuccessful, and the strength starts declining as the Rice Husk Ash percentage rises.
Effects of Different Aggressive Conditions on Cement Mortars Containing Rice Husk Ash
2018
The rice husk is an organic waste and is the result of the removal of the grains of the paddy grains during the grinding process of paddy. The rice husk ash is obtained by incinerating the rice husk. In this study, 40x40x160 mm prisms were produced for the bending and compressive strengths by replacing the cement 10%, 20% and 30% of the weight of the rice husk ash. Produced mortar samples were and sea water. Concretes produced by rice husk ash replacement are less permeable and more resistant to aggressive waters. An economy will also be achieved at the same time by replacing the rice husk ash with cement.
Contribution Of Rice Husk Ash To The Properties Of Cement Mortar And Concrete
2013
In the last decade, the use of supplementary cementing materials has become an integral part of high strength and high performance concrete mix design. These can be natural materials, byproducts or industrial wastes, or the ones requiring less energy and time to produce. Some of the commonly used supplementary cementing materials are fly ash, Silica Fume (SF), Ground Granulated Blast Furnace Slag (GGBFS) and Rice Husk Ash (RHA) etc. RHA is a by-product material obtained from the combustion of rice husk which consists of non-crystalline silicon dioxide with high specific surface area and high pozzolanic reactivity. It is used as pozzolanic material in mortar and concrete, and has demonstrated significant influence in improving the mechanical and durability properties of mortar and concrete. This paper presents an overview of the work carried out on the use of RHA as partial replacement of cement in mortar and concrete. Reported properties in this study are the mechanical and fresh properties of mortar/concrete. The optimal level of replacement of RHA in cement is also reported in this paper.
Strength of Mortar and Concrete as Influenced by Rice Husk Ash: A Review
World applied sciences journal, 2012
3 Abstract: Due to the pozzolanic reactivity, rice husk ash (RHA) is used as supplementary cementing material in mortar and concrete and has demonstrated significant influence in improving the mechanical and durability properties of mortar and concrete. It has economical and technical advantages to use in concrete. In this paper, a critical review on the influences of RHA on the strength of mortar and concrete are mainly presented. In addition, properties and pozzolanic activity of RHA, advantages and disadvantages of supplementary use of RHA in mortar/concrete are mentioned here. Based on the available documented literature, it can be concluded that RHA could be used as supplementary cementing material up to a certain level of replacement (about 20-30% of binder) without sacrificing strength of concrete. Proper consumption of these RHA contributes in solving environmental pollution and production of cost-effective concrete; it can also play a vital role for the production of sustai...
IJERT-Contribution Of Rice Husk Ash To The Properties Of Cement Mortar And Concrete
International Journal of Engineering Research and Technology (IJERT), 2013
https://www.ijert.org/contribution-of-rice-husk-ash-to-the-properties-of-cement-mortar-and-concrete https://www.ijert.org/research/contribution-of-rice-husk-ash-to-the-properties-of-cement-mortar-and-concrete-IJERTV2IS2598.pdf In the last decade, the use of supplementary cementing materials has become an integral part of high strength and high performance concrete mix design. These can be natural materials, by-products or industrial wastes, or the ones requiring less energy and time to produce. Some of the commonly used supplementary cementing materials are fly ash, Silica Fume (SF), Ground Granulated Blast Furnace Slag (GGBFS) and Rice Husk Ash (RHA) etc. RHA is a by-product material obtained from the combustion of rice husk which consists of non-crystalline silicon dioxide with high specific surface area and high pozzolanic reactivity. It is used as pozzolanic material in mortar and concrete, and has demonstrated significant influence in improving the mechanical and durability properties of mortar and concrete. This paper presents an overview of the work carried out on the use of RHA as partial replacement of cement in mortar and concrete. Reported properties in this study are the mechanical and fresh properties of mortar/concrete. The optimal level of replacement of RHA in cement is also reported in this paper.
Open Journal of Civil Engineering, 2024, 14, 65-81 https://www.scirp.org/journal/ojce ISSN Online: 2164-3172 ISSN Print: 2164-3164, 2024
Increasing the population and infrastructure in both emerging and developed countries requires a considerable amount of cement, which significantly affects the environment. The primary materials of concrete ('cement') production emit a large quantity of CO 2 into the environment. Also, the cost of conventional building materials like cement gives motivation to find geopolymer waste materials for concrete. To reduce harmful effects on the environment and cost of traditional concrete substance, alternative waste materials like rice husk ash (RHA), ground granulated blast-furnace (GGBS), fly ash (FA), and metakaolin (MK) can be used due to their pozzolanic behavior. RHA waste material with a high silica concentration obtained from burning rice husks can possibly be used as a supplementary cementitious material (SCM) in the manufacturing of concrete, and its strong pozzolanic properties can contribute to the strength and impermeability of concrete. This review paper highlights a summary of the positive effect of using RHA as a partial substitute for cement in building construction, as well as its optimal inclusion of enhanced mechanical properties like compressive strength, flexural strength, and split tensile strength of mortar and concrete.