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Sulphate attack in concrete is one of the common and aggressive actions that lead to concrete det... more Sulphate attack in concrete is one of the common and aggressive actions that lead to concrete deterioration. The compounds responsible for sulphate attack on concrete are water-soluble sulphate-containing salts, such as alkali-earth (calcium, magnesium) and alkali (sodium, potassium) sulphates that are capable of chemically reacting with components of concrete. Solution of these sulphates reacts with hydration products of the tri-calcium aluminates (C3A) phase of Portland cement, and with calcium hydroxide {Ca(OH)2} forming an expansive crystalline product called ettringite (Ca6[Al(OH)6]2(SO4)3.26H2O).The structure of this ettringite is shown in Figure 1. Ettringite formation alters the concrete crystal composition and causes expansion which leads to the development of tensile stresses in the concrete as well as crack formation. These cracks allow easy ingress for more sulphates into the concrete and the deterioration accelerates. The effects of sulphate attack on the concrete hydra...

Concrete is widely used in the construction of infrastructures and also, its compressive strength... more Concrete is widely used in the construction of infrastructures and also, its compressive strength determines the function under the application of load. This research investigated the effect of curing media on compressive strength of microbial laterized concrete. 216 numbers of microbial laterized concrete cubes (150x150x150mm) batched by volume at 1:2:4 and water cement ratio of 0.5 were produced from Portland lime cement, aggregates (fine and coarse), laterite and bacteria (bacillus sp. Ct-5) water. Laterite was added at 0%, 15% and 30% respectively. They were then cured in four curing media; Distilled Water, Bacteria + Nutrient Broth Water, Bacteria Water, and Nutrient Broth Water for 28days. Compressive strength test was carried out at 7, 14, and 28 days respectively and some of the results were recorded as 17.38 kN/m 2 , 22.00 kN/m 2 , 22.24 kN/m 2 etc. The result shows that the compressive strength 22.24 kN/m 2 of concrete produced with zero percent laterite, mixed with bacill...

The notable demand for the want of cement in our time has stimulated increment in cement producti... more The notable demand for the want of cement in our time has stimulated increment in cement production and increment in manufacturers to be had in our day. These in turn amongst others have brought about failure of buildings and other construction members. As a result, the need to ensure the quality of available cement in circulation is of utmost paramount. This research work studies the available Portland lime cement of grade 42.5 only, in Nigeria from such company as company A, company B, and company C. The qualities and properties of the Portland lime cement from every of the above-named companies were investigated and as compared. Properties like Fineness, Setting Time, Chemical composition, Specific gravity, Consistency, Loss of ignition, Strength (compressive strength, and flexural strength), Micro structural analysis were determined according to relevant BS EN 197-1 (2011) and (ASTMC) 150-92 standards. These tests were carried out with the usage of scanning electron microscope, X-ray fluorescence spectrometer, Vicat apparatus, compressive strength machine, consistency apparatus and Chatelier flask, among others. The results showed that the chemical composition mostly of CaO, SiO2, AL2O3 and MgO in the cement +are within the acceptable limit of 60.0-67.0, 17.0-25.0, 3.0-8.0 and 0.1-4.0 respectively in the BS 4550: Part 3 (1979). The results of the compressive strength acquired for all the cement have been a way beneath the standardized result expected for grade 42.5. These could partly be traced to the cement micro-structure as Company C with the best morphology exhibits better compressive strength than others. Improvement on the cement morphology by the manufacturers could lead to compressive strength improvement. It was also discovered that one of the important factors that would have contributed to the low compressive strength was excessive amount of silt/clay content material inside the sand used.

FUOYE Journal of Engineering and Technology

Concrete is one of the most common and widely applied construction materials in the world. It is ... more Concrete is one of the most common and widely applied construction materials in the world. It is good in compression but weak in tension. The weakness in tension is been catered for through the use of reinforcement but there is still need to ensure that its minimum tensile strength is retained during the course of production and usage to avoid cracks development at the reinforcement cover. Concrete mixes of 1:2:4 (cement: sand: granite) and mortar of 1:6 mix ratio of cement to sand were produced. The ordinary Portland cement (OPC) content was partially replaced with bamboo leaf ash (BLA) from 0% to 12% at 2% interval. They were tested under normal and elevated temperature to know the effect of elevated temperature on their splitting tensile strength. The results obtained showed OPC concrete mix to improve in splitting tensile strength (3.5 N/mm2 to 3.7 N/mm2 at 28 days curing) whereas there was a decrease in the splitting tensile strength obtained for BLA mixes (3.29 N/mm2 to 1.75...

International Journal of World Policy and Development Studies

The notable demand for the want of cement in our time has stimulated increment in cement producti... more The notable demand for the want of cement in our time has stimulated increment in cement production and increment in manufacturers to be had in our day. These in turn amongst others have brought about failure of buildings and other construction members. As a result, the need to ensure the quality of available cement in circulation is of utmost paramount. This research work studies the available Portland lime cement of grade 42.5 only, in Nigeria from such company as company A, company B, and company C. The qualities and properties of the Portland lime cement from every of the above-named companies were investigated and as compared. Properties like Fineness, Setting Time, Chemical composition, Specific gravity, Consistency, Loss of ignition, Strength (compressive strength, and flexural strength), Micro structural analysis were determined according to relevant BS EN 197-1 (2011) and (ASTMC) 150-92 standards. These tests were carried out with the usage of scanning electron microscope, ...

Journal of Applied Sciences and Environmental Management, 2017

Pozzolans have been discovered recently to be of various benefits to the construction industries ... more Pozzolans have been discovered recently to be of various benefits to the construction industries and various researches are on the high gear to further discover, proof and established their suitability as substitute to cement. This research work has therefore work on the effectiveness of bamboo leaf ash (BLA) and locust beans pod ash (LPBA) as pozzolans with reference to crystal and microstructure of its hydrated paste. Ordinary Portland cement was partially replaced with BLA and LPBA at different percentages, concrete pastes were made and cured at 7 and 28 days for the tests. The research work has been carried out using compressive strength test, X-ray fluorescence spectrometer, X-ray diffraction analysis as well as scanning electron microscopy to discover, present and analyze the quality and quantity of composition and hydration behavior of the different paste. The tests established BLA and LBPA as capable of successfully replacing cement in concrete production with added advantages in the properties of such concrete in term of mineral composition and microstructure interlocking. © JASEM

Journal of Materials Science and Chemical Engineering, 2018

Recent researches show that agricultural wastes can be reuse as pozolans; this contributes to our... more Recent researches show that agricultural wastes can be reuse as pozolans; this contributes to our environmental sustenance. The need to successful carry out proper analysis contributes significantly to improving the overall use of the discovered pozolans. Therefore, this research aims to investigate the micro-structural and chemical analysis of some selected pozzolans at different calcinating temperatures. Rich husk ash (RHA), groundnut shell ash (GSA), locust beans pod ash (LBPA) and bamboo leaf ash (BLA) were obtained; their chemical and microstructural analysis at different calcinating temperatures (500˚C, 600˚C and 700˚C) were carried out using X-ray fluorescence and scanning electron microscope. The results show that the optimum calcinating temperatures considering the microstructure and chemical composition of RHA, BLA and LBPA were 700˚C, 500˚C and 600˚C respectively. These pozzolans were also classified according to ASTM 618 requirement.

The growing concern for the environment all over the world, as well as the high cost of Portland ... more The growing concern for the environment all over the world, as well as the high cost of Portland cement has placed limitation on its use as the sole binding material in concrete. This work has shown that ashes from some agricultural or other biogenic wastes when mixed with appropriate amounts of ordinary Portland cement (OPC) can be used as low-cost, environmentally, more friendly binders for concrete production, than using OPC alone. Experimental determination of requisite properties of the ashes of rice husk, coconut husk, palm leaf, bamboo leaf and peanut shell revealed that they satisfy the essential requirements for pozzolans. Further experimental work was carried out on OPC/rice husk ash (RHA) and OPC/coconut husk ash (CHA) concretes to determine their essential properties in fresh and hardened states. Although the initial and final setting times of OPC/RHA and OPC/CHA pastes were longer than the setting times of 100% OPC paste, they are all within the limits specified by relevant standards. The workability of fresh concrete produced by partially replacing OPC with either of RHA and CHA was found to be better than with 100% OPC. It was also shown that the porosity of OPC/RHA and OPC/CHA concretes was less than the porosity of OPC concrete. Strength tests using very finely ground RHA and CHA to partially replace Portland cement in concrete production showed that at up to 15% replacement the strength activity index of each of them is greater than 100%, which indicating that they are excellent pozzolans.

Sulphate attack in concrete is one of the common and aggressive actions that lead to concrete det... more Sulphate attack in concrete is one of the common and aggressive actions that lead to concrete deterioration. The compounds responsible for sulphate attack on concrete are water-soluble sulphate-containing salts, such as alkali-earth (calcium, magnesium) and alkali (sodium, potassium) sulphates that are capable of chemically reacting with components of concrete. Solution of these sulphates reacts with hydration products of the tri-calcium aluminates (C3A) phase of Portland cement, and with calcium hydroxide {Ca(OH)2} forming an expansive crystalline product called ettringite (Ca6[Al(OH)6]2(SO4)3.26H2O).The structure of this ettringite is shown in Figure 1. Ettringite formation alters the concrete crystal composition and causes expansion which leads to the development of tensile stresses in the concrete as well as crack formation. These cracks allow easy ingress for more sulphates into the concrete and the deterioration accelerates. The effects of sulphate attack on the concrete hydra...

Concrete is widely used in the construction of infrastructures and also, its compressive strength... more Concrete is widely used in the construction of infrastructures and also, its compressive strength determines the function under the application of load. This research investigated the effect of curing media on compressive strength of microbial laterized concrete. 216 numbers of microbial laterized concrete cubes (150x150x150mm) batched by volume at 1:2:4 and water cement ratio of 0.5 were produced from Portland lime cement, aggregates (fine and coarse), laterite and bacteria (bacillus sp. Ct-5) water. Laterite was added at 0%, 15% and 30% respectively. They were then cured in four curing media; Distilled Water, Bacteria + Nutrient Broth Water, Bacteria Water, and Nutrient Broth Water for 28days. Compressive strength test was carried out at 7, 14, and 28 days respectively and some of the results were recorded as 17.38 kN/m 2 , 22.00 kN/m 2 , 22.24 kN/m 2 etc. The result shows that the compressive strength 22.24 kN/m 2 of concrete produced with zero percent laterite, mixed with bacill...

The notable demand for the want of cement in our time has stimulated increment in cement producti... more The notable demand for the want of cement in our time has stimulated increment in cement production and increment in manufacturers to be had in our day. These in turn amongst others have brought about failure of buildings and other construction members. As a result, the need to ensure the quality of available cement in circulation is of utmost paramount. This research work studies the available Portland lime cement of grade 42.5 only, in Nigeria from such company as company A, company B, and company C. The qualities and properties of the Portland lime cement from every of the above-named companies were investigated and as compared. Properties like Fineness, Setting Time, Chemical composition, Specific gravity, Consistency, Loss of ignition, Strength (compressive strength, and flexural strength), Micro structural analysis were determined according to relevant BS EN 197-1 (2011) and (ASTMC) 150-92 standards. These tests were carried out with the usage of scanning electron microscope, X-ray fluorescence spectrometer, Vicat apparatus, compressive strength machine, consistency apparatus and Chatelier flask, among others. The results showed that the chemical composition mostly of CaO, SiO2, AL2O3 and MgO in the cement +are within the acceptable limit of 60.0-67.0, 17.0-25.0, 3.0-8.0 and 0.1-4.0 respectively in the BS 4550: Part 3 (1979). The results of the compressive strength acquired for all the cement have been a way beneath the standardized result expected for grade 42.5. These could partly be traced to the cement micro-structure as Company C with the best morphology exhibits better compressive strength than others. Improvement on the cement morphology by the manufacturers could lead to compressive strength improvement. It was also discovered that one of the important factors that would have contributed to the low compressive strength was excessive amount of silt/clay content material inside the sand used.

FUOYE Journal of Engineering and Technology

Concrete is one of the most common and widely applied construction materials in the world. It is ... more Concrete is one of the most common and widely applied construction materials in the world. It is good in compression but weak in tension. The weakness in tension is been catered for through the use of reinforcement but there is still need to ensure that its minimum tensile strength is retained during the course of production and usage to avoid cracks development at the reinforcement cover. Concrete mixes of 1:2:4 (cement: sand: granite) and mortar of 1:6 mix ratio of cement to sand were produced. The ordinary Portland cement (OPC) content was partially replaced with bamboo leaf ash (BLA) from 0% to 12% at 2% interval. They were tested under normal and elevated temperature to know the effect of elevated temperature on their splitting tensile strength. The results obtained showed OPC concrete mix to improve in splitting tensile strength (3.5 N/mm2 to 3.7 N/mm2 at 28 days curing) whereas there was a decrease in the splitting tensile strength obtained for BLA mixes (3.29 N/mm2 to 1.75...

International Journal of World Policy and Development Studies

The notable demand for the want of cement in our time has stimulated increment in cement producti... more The notable demand for the want of cement in our time has stimulated increment in cement production and increment in manufacturers to be had in our day. These in turn amongst others have brought about failure of buildings and other construction members. As a result, the need to ensure the quality of available cement in circulation is of utmost paramount. This research work studies the available Portland lime cement of grade 42.5 only, in Nigeria from such company as company A, company B, and company C. The qualities and properties of the Portland lime cement from every of the above-named companies were investigated and as compared. Properties like Fineness, Setting Time, Chemical composition, Specific gravity, Consistency, Loss of ignition, Strength (compressive strength, and flexural strength), Micro structural analysis were determined according to relevant BS EN 197-1 (2011) and (ASTMC) 150-92 standards. These tests were carried out with the usage of scanning electron microscope, ...

Journal of Applied Sciences and Environmental Management, 2017

Pozzolans have been discovered recently to be of various benefits to the construction industries ... more Pozzolans have been discovered recently to be of various benefits to the construction industries and various researches are on the high gear to further discover, proof and established their suitability as substitute to cement. This research work has therefore work on the effectiveness of bamboo leaf ash (BLA) and locust beans pod ash (LPBA) as pozzolans with reference to crystal and microstructure of its hydrated paste. Ordinary Portland cement was partially replaced with BLA and LPBA at different percentages, concrete pastes were made and cured at 7 and 28 days for the tests. The research work has been carried out using compressive strength test, X-ray fluorescence spectrometer, X-ray diffraction analysis as well as scanning electron microscopy to discover, present and analyze the quality and quantity of composition and hydration behavior of the different paste. The tests established BLA and LBPA as capable of successfully replacing cement in concrete production with added advantages in the properties of such concrete in term of mineral composition and microstructure interlocking. © JASEM

Journal of Materials Science and Chemical Engineering, 2018

Recent researches show that agricultural wastes can be reuse as pozolans; this contributes to our... more Recent researches show that agricultural wastes can be reuse as pozolans; this contributes to our environmental sustenance. The need to successful carry out proper analysis contributes significantly to improving the overall use of the discovered pozolans. Therefore, this research aims to investigate the micro-structural and chemical analysis of some selected pozzolans at different calcinating temperatures. Rich husk ash (RHA), groundnut shell ash (GSA), locust beans pod ash (LBPA) and bamboo leaf ash (BLA) were obtained; their chemical and microstructural analysis at different calcinating temperatures (500˚C, 600˚C and 700˚C) were carried out using X-ray fluorescence and scanning electron microscope. The results show that the optimum calcinating temperatures considering the microstructure and chemical composition of RHA, BLA and LBPA were 700˚C, 500˚C and 600˚C respectively. These pozzolans were also classified according to ASTM 618 requirement.

The growing concern for the environment all over the world, as well as the high cost of Portland ... more The growing concern for the environment all over the world, as well as the high cost of Portland cement has placed limitation on its use as the sole binding material in concrete. This work has shown that ashes from some agricultural or other biogenic wastes when mixed with appropriate amounts of ordinary Portland cement (OPC) can be used as low-cost, environmentally, more friendly binders for concrete production, than using OPC alone. Experimental determination of requisite properties of the ashes of rice husk, coconut husk, palm leaf, bamboo leaf and peanut shell revealed that they satisfy the essential requirements for pozzolans. Further experimental work was carried out on OPC/rice husk ash (RHA) and OPC/coconut husk ash (CHA) concretes to determine their essential properties in fresh and hardened states. Although the initial and final setting times of OPC/RHA and OPC/CHA pastes were longer than the setting times of 100% OPC paste, they are all within the limits specified by relevant standards. The workability of fresh concrete produced by partially replacing OPC with either of RHA and CHA was found to be better than with 100% OPC. It was also shown that the porosity of OPC/RHA and OPC/CHA concretes was less than the porosity of OPC concrete. Strength tests using very finely ground RHA and CHA to partially replace Portland cement in concrete production showed that at up to 15% replacement the strength activity index of each of them is greater than 100%, which indicating that they are excellent pozzolans.