scholarly journals Utilization of Corn Cobs Ash as Cementitious and Binary Cementitious Materials in Concrete and Cement-based Composites: A Review

2021 ◽  
pp. 26-42
Keyword(s):  
Compressive Strength ◽  
Energy Savings ◽  
Low Cost ◽  
Cementitious Materials ◽  
Pulse Velocity ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Biomass Ash ◽  
Operational Conditions ◽  
Corn Cobs

This paper reviews the utilization of corn cobs ash (CCA) as pozzolanic, cementitious, and binary cementitious materials in concrete. CCA is the grey-to-brown, inorganic or heterogeneous residual material derived from the high- temperature incineration or combustion of corn cobs (CC). Despite the typical problematic nature of biomass ash, the chemical composition of CCA renders it a potential pozzolanic material. Therefore, numerous studies have critically examined the process technologies and operational conditions for CCA production and its application as a partial replacement for cement in concrete. Other studies have extensively characterized the physicochemical, morphological, microstructure, and thermal properties of CCA through various analytical techniques. Potential pozzolanic materials must meet the condition: SiO2 + Al2O3 + Fe2O3 ≥ 70%, according to ASTM C618, to which CCA complies satisfactorily. Hence, the use of CCA as a replacement for cement has been investigated over the years. Findings indicate that the partial replacement of cement with CCA decreases compressive strength, thermal conductivity, ultrasonic pulse velocity, and density of the hardened concrete at normal temperatures. Nevertheless, the thermal treatment (calcination) of CCA and extended curing enhances compressive strength owing to higher silica content and extended surface area. Besides, the partial replacement of cement with CCA enhances the insulation properties of mortar, which improves thermal comfort, costs and energy savings in buildings. Hence, the partial replacement of cement with CCA provides an environmentally friendly, low cost, and sustainable approach for valorizing CC residues whilst addressing CO2 emissions in construction.

scholarly journals Evolution of Mechanical Properties with Time of Fly-Ash-Based Geopolymer Mortars under the Effect of Granulated Ground Blast Furnace Slag Addition

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1135 ◽  
Author(s):  
Mateusz Sitarz ◽  
Izabela Hager ◽  
Marta Choińska
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Fly Ash ◽  
Modulus Of Elasticity ◽  
Blast Furnace Slag ◽  
Energy Savings ◽  
Pulse Velocity ◽  
Partial Replacement ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag

Geopolymers are considered to alternatives to Portland cement, providing an opportunity to exploit aluminosilicate wastes or co-products with promising performances in the construction sector. This research is aimed at investigating the strength of fly-ash-geopolymers of different ages. The effect of granulated blast furnace slag (GGBFS) as a partial replacement of fly ash (FA) on the tensile (ft) and compressive strength (fc), as well as the modulus of elasticity, is investigated. The main advantage of the developed geopolymer mixes containing GGBFS is their ability to set and harden at room temperature with no need for heating to obtain binding properties, reducing the energy consumption of their production processes. This procedure presents a huge advantage over binders requiring heat curing, constituting a significant energy savings and reduction of CO2 emissions. It is found that the development of strength strongly depends on the ratio of fly-ash to granulated blast furnace slag. With the highest amount of GGBFS, the compressive strength of geopolymers made of fly-ash reached 63 MPa after 28 days of curing at ambient temperature. The evolution of compressive strength with time is correlated with the development of ultrasound pulse velocity methods, which are used to evaluate maturity. The modulus of elasticity changes with strength and the relationship obtained for the geopolymer is presented on the basis of typical models used for cement-based materials. The tensile to compressive strength ratios of the tested geopolymers are identified as higher than for cementitious binders, and the ft(fc) relationship is juxtaposed with dependencies known for cement binders, showing that the square root function gives the best fit to the results.

scholarly journals EFFECT OF VOLCANIC ASH AS PARTIAL REPLACEMENT OF CEMENT IN CONCRETE SUBJECT TO AGGRESSIVE CHEMICAL ENVIRONEMNT

2021 ◽  
Vol 6 (5) ◽  
Author(s):  
Agboola Shamsudeen Abdulazeez ◽  
Amina Omolola Suleiman ◽  
Simdima Gabriel Gideon ◽  
Solomon Wutong Poki
Keyword(s):  
Compressive Strength ◽  
Volcanic Ash ◽  
Setting Time ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Target Strength ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Split Tensile Strength ◽  
Concrete Production

- Presently researches all over the world is concentrating on alternative materials as partial cement replacement in concrete production. The use of pozzolanic material in concrete is becoming increasingly important because of the need for more sustainable cementing products. Volcanic ash is a form of natural pozzolan and has a chemical composition comparable to other supplementary cementitious materials. In this paper, volcanic ash was used to partially replace cement in the ratio of 0%, 5%, 10%, 15% and 20% by volume in concrete and cured in H2SO4 and MgSO4 environment. 28-day target strength was adopted and concrete tested at 7, 14, 28 and 56 days’ hydration period. Specific gravity, bulk density and setting time test on volcanic ash were carried out. Fresh concrete tests such as slump and compacting factor test were carried out along-side hardened concrete tests like compressive strength and split tensile strength. The result shows that the maximum compressive strength at 28 days was at 0% control concrete, while at 56 days the maximum strength was observed at 10% replacement of cement with volcanic ash and it is considered as optimum percentage replacement.

scholarly journals Performance Evaluation of Concrete using Marble Mining Waste

2016 ◽  
Vol 11 (2) ◽  
pp. 53-66 ◽  
Author(s):  
Sudarshan Dattatraya Kore ◽  
A. K. Vyas
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Mining Waste ◽  
Partial Replacement ◽  
Infrastructure Development ◽  
The Impact ◽  
Marble Waste

Abstract A huge amount waste (approximately 60%) is generated during mining and processing in marble industries. Such waste can be best utilized in infrastructure development works. Coarse aggregate 75% by weight was replaced by aggregate obtained from marble mining waste. The impact of marble waste as a partial replacement for conventional coarse aggregate on the properties of concrete mixes such as workability, compressive strength, permeability, abrasion, etc. was evaluated. The test results revealed that the compressive strength was comparable to that of control concrete. Other properties such as workability of concrete increased, water absorption reduced by 17%, and resistance to abrasion was marginally increased by 2% as compared to that of control concrete. Ultrasonic pulse velocity and FTIR results show improvement in quality of concrete with crushed marble waste. From the TGA analysis it was confirmed that, aggregate produced from marble waste shows better performance under elevated temperature than that of conventional aggregates.

scholarly journals Utilization of Sugarcane Bagasse Ash from Power Co-generation Boilers as a Supplementary Cementitious Material

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Safiki Ainomugisha ◽  
Bisaso Edwin ◽  
Bazairwe Annet
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Sugarcane Bagasse ◽  
Low Income ◽  
Ordinary Portland Cement ◽  
Construction Material ◽  
Sustainable Construction ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Sugarcane Bagasse Ash

Concrete has been the world’s most consumed construction material, with over 10 billion tons of concrete annually. This is mainly due to its excellent mechanical and durability properties plus high mouldability. However, one of its major constituents; Ordinary Portland Cement is reported to be expensive and unaffordable by most low-income earners. Its production contributes about 5%–8% of global CO2 greenhouse emissions. This is most likely to increase exponentially with the demand of Ordinary Portland Cement estimated to rise by 200%, reaching 6000 million tons/year by 2050.  Therefore, different countries are aiming at finding alternative sustainable construction materials that are more affordable and offer greener options reducing reliance on non-renewable sources. Therefore, this study aimed at assessing the possibility of utilizing sugarcane bagasse ash from co-generation in sugar factories as supplementary material in concrete. Physical and chemical properties of this sugarcane bagasse ash were obtained plus physical and mechanical properties of fresh and hardened concrete made with partial replacement of Ordinary Portland Cement. Cost-benefit analysis of concrete was also assessed. The study was carried using 63 concrete cubes of size 150cm3 with water absorption studied as per BS 1881-122; slump test to BS 1881-102; and compressive strength and density of concrete according to BS 1881-116. The cement binder was replaced with sugarcane bagasse ash 0%, 5%, 10%, 15%, 20%, 25% and 30% by proportion of weight. Results showed the bulk density of sugarcane bagasse ash at 474.33kg/m3, the specific gravity of 1.81, and 65% of bagasse ash has a particle size of less than 0.28mm. Chemically, sugarcane bagasse ash contained SiO2, Fe2O3, and Al2O3 at 63.59%, 3.39%, and 5.66% respectively. A 10% replacement of cement gave optimum compressive strength of 26.17MPa. This 10% replacement demonstrated a cost saving of 5.65% compared with conventional concrete. 

scholarly journals Influence of Partial Replacement of Micro-Silica by Fly-Ash on Strength Properties of Reactive Powder Concrete

2020 ◽  
Vol 9 (3) ◽  
pp. 2932-2937
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Fly Ash ◽  
Mechanical Performance ◽  
Cementitious Materials ◽  
Partial Replacement ◽  
Reactive Powder Concrete ◽  
Experimental Investigations ◽  
Reactive Powder ◽  
Micro Silica

Reactive powder concrete (RPC) is the ultra-high strength concrete made by cementitious materials like silica fumes, cement etc. The coarse aggregates are completely replaced by quartz sand. Steel fibers which are optional are added to enhance the ductility. Market survey has shown that micro-silica is not so easily available and relatively costly. Therefore an attempt is made to experimentally investigate the reduction of micro-silica content by replacing it with fly-ash and mechanical properties of modified RPC are investigated. Experimental investigations show that compressive strength decreases gradually with addition of the fly ash. With 10 per cent replacement of micro silica, the flexural and tensile strength showed 40 and 46 per cent increase in the respective strength, though the decrease in the compressive strength was observed to be about 20 per cent. For further percentage of replacement, there was substantial drop in compressive, flexural as well as tensile strength. The experimental results thereby indicates that utilisation of fly-ash as a partial replacement to micro silica up to 10 per cent in RPC is feasible and shows quite acceptable mechanical performance with the advantage of utilisation of fly-ash in replacement of micro-silica.

On Effects of Fly Ash as a Partial Replacement of Cement on Concrete Strength

2012 ◽  
Vol 204-208 ◽  
pp. 3970-3973
Author(s):  
Reagan J. Case ◽  
Kai Duan ◽  
Thuraichamy G. Suntharavadivel
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Concrete Strength ◽  
Cementitious Materials ◽  
Partial Replacement ◽  
Replacement Ratio ◽  
Interface Reactions ◽  
Compressive Strength Of Concrete ◽  
Interface Bonding Strength ◽  
Large Research

As a part of a large research program aiming at the cementitious materials containing recycled materials at Central Queensland University – Australia, the current paper presents the preliminary results of a study on the effects of fly ash, which is used to replace cement in concrete, on the concrete compressive strength. For this purpose, systematic experiments have been carried out to investigate the influences of fly ash ratio and age. The compressive strength of concrete specimens with replacement ratios of 15%, 30% and 45%, and aged 7 and 28 days are measured and are compared with those of the concrete specimens without fly ash at the same ages. The results demonstrate that the strength of fly ash containing concrete improves more slowly but more strongly with aging, than their fly ash free counterparts, and an optimum fly ash replacement ratio exists where the maximum compressive strength of fly ash containing concrete can be achieved, and the maximum strength for the specimens aged 28 days and above is higher that of fly ash free concrete. Furthermore, the observation strength behaviours are analysed and discussed in terms of the influences of fly ash on interface reactions and interface bonding strength.

scholarly journals Concrete using sawdust as partial replacement of sand : Is it strong and does not endanger health?

2019 ◽  
Vol 258 ◽  
pp. 01015 ◽  
Author(s):  
Nurul Huda Suliman ◽  
Amir Atif Abdul Razak ◽  
Hazrina Mansor ◽  
Anizahyati Alisibramulisi ◽  
Norliyati Mohd Amin
Keyword(s):  
Compressive Strength ◽  
Construction Cost ◽  
Material Testing ◽  
Partial Replacement ◽  
Environmental Study ◽  
Hardened Concrete ◽  
Consumer Health ◽  
River Sand ◽  
Environmental Laboratory ◽  
Hazardous Use

This study was conducted to investigate the effectiveness of concrete using sawdust to partially replace the river sand which could reduce both environmental problems and construction cost. In this study, sawdust concrete has been produced where the river sand is replaced with sawdust by 5%, 10% and 15% of the total sand volume. Both wet concrete and hardened concrete (cubes specimens) were tested through material testing and cube testing to obtain the most optimum sawdust concrete design. In addition, specimens have also been tested in environmental laboratory to identify the extent of hazardous use of sawdust to consumer health. This is because the dust used is the waste taken from the unknown root of the level of cleanliness. The result shows that the most optimum design for producing sawdust concrete is that with 10% replacement of river sand. The result is based on the compressive strength obtained. The results of environmental study also show that this sawdust concrete is free from any harmful to health contaminants.

Assessment of mechanical and fire resistance for hybrid nano-clay and steel fibres concrete at different curing ages

2019 ◽  
Vol 11 (2) ◽  
pp. 189-203 ◽  
Author(s):  
Ola Bakr Shalby ◽  
Hala Mohamed Elkady ◽  
Elsayed Abdel Raouf Nasr ◽  
Mohamed Kohail
Keyword(s):  
Compressive Strength ◽  
Residual Strength ◽  
Low Cost ◽  
Partial Replacement ◽  
Fire Exposure ◽  
Content Type ◽  
Steel Fibres ◽  
Concrete Properties ◽  
Nano Clay ◽  
Concrete Mix

Purpose Nano-Clay (NC) is reported as a candidate partial replacement for cement, due to its abundance and relatively low cost - beside reported promotion of different concrete properties. On the other hand, Steel Fibres (SF) has proven to have a positive effect on post fire exposure residual strength of concrete. This paper aims to present the outcomes of a comprehensive research program assessing a hybrid mix between NC and SF in concrete mixtures (NCSF-CRETE). Design/methodology/approach Physical chemical and physical characterization of NC is performed using different tools as XRF spectrometer, and TEM micrograph. Fresh concrete properties of NSCF-CRETE as slump and air content are investigated. Enhancement in permeability using NSCF is verified by comparing its resistance to the penetration of chlorides resistance with regular concrete mix. Besides, the proposed NCSF-CRETE compressive strength is evaluated compared to mixes with NC and SF each used separately at different curing ages. Besides, NSCF and compared mixes are exposed to an indirect fire testing program – two hours exposure – for: 300, 450 and 600°C. Degradation in compressive strength was investigated after exposure to different temperatures and percentage of residual strength is reported. Findings Results indicated an improved performance of NCSF -CRETE of about 40% compared to regular concrete in compressive strength at normal conditions. This improvement extended to its behavior when subjected to indirect fire exposure NSCF also maintained 40% more strength than the residual in regular concrete mix – which suffered severe damage – after 2 h exposure to 600°C. Originality/value Using NCSF-Crete allows retrofitting the structure after exposure to such drastic conditions.

scholarly journals Influence of Rice Husk Ash Density on the Workability and Strength of Structural Concrete

2017 ◽  
Vol 2 (3) ◽  
pp. 36 ◽  
Author(s):  
John Kamau ◽  
Ash Ahmed ◽  
Fraser Hyndman ◽  
Paul Hirst ◽  
Joseph Kangwa
Keyword(s):  
Compressive Strength ◽  
Rice Husk ◽  
Water Demand ◽  
Rice Husk Ash ◽  
Concrete Strength ◽  
High Water ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Hardened Concrete ◽  
Structural Applications

Supplementary cementitious materials (SCMs) have been known to improve the properties of fresh and hardened concrete, and at the same time enhance the sustainability of concrete. Rice husk Ash (RHA), is one such material, but has neither been widely studied nor applied in practice. This work investigated the effect of the density of RHA on the workability and compressive strength of fresh and hardened RHA-replaced concrete respectively. Cement was replaced with RHA in concrete by weight (RHA-W) and by volume (RHA-V) at steps of 0%, 5%, 7.5%, 10%, 15%, 20%, 25% and 30%. The 0% replacement was used as the reference point from which performances were measured. Results showed that unlike the characteristic of other established pozzolans, RHA significantly reduced the workability of wet concrete and the rate of compressive strength gain over curing time due to a high water demand that is caused by the increased volume of replaced concrete, which results from its low density. Workability reduced with increased replacement for both RHA-W and RHA-V. Replacements of above 15% were not possible for the RHA-W due to the high water demand. However, replacements of up to 30% were achieved for the RHA-V. RHA-W specimens achieved lower compressive strengths and were observed to gain strength at a lower rate over the 28 to 91-days period of curing compared to RHA-V specimens. This behavior was attributed to the shortage of water that is necessary for the hydration of cement and subsequent pozzolanic reaction, which is the basis of the contribution that is made to the strength and performance of concrete by SCMs. However, the compressive strengths achieved were above the study’s target concrete strength of class C32/40 at 91 days, which is among those classes that are listed as being durable and suitable for structural applications. A conclusion that RHA should supplement cements by volumetric replacement rather than simple substitution by weight was drawn.

scholarly journals The Synergy between Bio-Aggregates and Industrial Waste in a Sustainable Cement Based Composite

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6158
Author(s):  
Cătălina Mihaela Grădinaru ◽  
Adrian Alexandru Șerbănoiu ◽  
Radu Muntean ◽  
Bogdan Vasile Șerbănoiu
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Fly Ash ◽  
Splitting Tensile Strength ◽  
Partial Replacement ◽  
Cement Matrix ◽  
Freeze Thaw ◽  
Corn Cobs ◽  
Study Results ◽  
Sunflower Stalks

The effects of the fly ash and of the sunflower stalks and corn cobs within a cement-matrix composite were studied under the aspects of density, compressive strength, splitting tensile strength, elasticity modulus, and resistance to repeated freeze-thaw cycles. In the research were developed 20 recipes of cement-based composite, including the reference composite. Fly ash was used as partial cement replacement (10, 20 and 30% by volume), and the vegetal aggregates made by corn cobs and sunflower stalks as partial replacement of the mineral aggregates (25 and 50% by volume). The study results revealed that a lightweight composite can be obtained with 50% of vegetal aggregates, and the fly ash, no matter its percentage, enhanced the compressive strength and splitting tensile strength of the compositions with 50% of sunflower aggregates and the freeze-thaw resistance of all compositions with sunflower stalks.

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