Supplementary Cementitious Material In Concrete Research Articles

Technical, economic, and environmental feasibility of rice hull ash from electricity generation as a mineral additive to concrete

A circular economy based on symbiotic relationships among sectors, where the waste from one is resource to another, holds promise for cost-effective and sustainable production. This research explores such a model for the agriculture, energy, and construction sectors in California. Here, we develop new an understanding for the synergistic utilization mechanisms for rice hull, a byproduct from rice production, as a feedstock for electricity generation and rice hull ash (RHA) used as a supplementary cementitious material in concrete. A suite of methods including experimental analysis, techno-economic analysis (TEA), and life-cycle assessment (LCA) were applied to estimate the cost and environmental performance of the system. TEA results showed that the electricity price required for break even on expenses without selling RHA is $0.07/kWh, lower than the market price. As such, RHA may be available at little to no cost to concrete producers. Our experimental results showed the viability of RHA to be used as a supplementary cementitious material, meaning it can replace a portion of the cement used in concrete. LCA results showed that replacing 15% of cement with RHA in concrete can reduce carbon dioxide equivalent (CO2e) emissions by 15% while still meeting material performance targets. While the substitution rate of RHA for cement may be modest, RHA generated from California alone could mitigate 0.2% of total CO2e from the entire cement production sector in the United States and 1% in California.

Mechanical, microstructural characteristics and sustainability analysis of concrete incorporating date palm ash and eggshell powder as ternary blends cementitious materials

Cement production causes a threat to environmental sustainability owing to the enormous volume of greenhouse gas releases and high energy consumption. Similarly, agro-industrial waste contributed significantly to environmental pollution when disposed of in landfills. Waste from date palms is one of the main agro-waste generated in Saudi Arabia. This waste is normally disposed of without treatment or burnt for energy. The date palm ash (DPA) due to its pozzolanic properties could be suitable for use as supplementary cementitious material (SCM) in concrete. However, due to its weak or slower pozzolanic reactivity, the DPA negatively affects the performance of concrete. In this research, the DPA was used as a SCM in concrete. Eggshell powder (ESP) owing to its abundant calcium oxide content was used as an additive to the concrete containing other pozzolanic materials with high silica content. Cement was partially replaced with DPA at dosages between 10% to 40%, and ESP was added at different proportions between 1% to 4% by weight of the binder. The workability of the concrete was decreased with adding blends of DPA and ESP. The mechanical strengths (compressive, flexural, and tensile strengths), modulus of elasticity (MoE), water absorption, and porosity of the concrete were negatively affected by adding DPA. Blending up to 30% DPA with up to 3% ESP as cementitious materials help alleviate the adverse effects of the DPA on the strengths, MoE, and durability performance of the concrete. DPA increases pore volume and porosity by decelerating C-S-H production through its slower pozzolanic reaction at early ages. DPA reduced total embodied CO2 emissions and enhanced the eco-strength efficiency of the concrete. Using DPA and ESP blends in concrete improves performance, minimizes environmental effects, and reduces CO2 emissions during cement production.

Experimental investigation and modelling of the mechanical properties of palm oil fuel ash concrete using Scheffe’s method

This study explores the enhancement of mechanical properties in concrete blended with palm oil fuel ash (POFA) through Scheffe's optimization. The utilization of POFA as supplementary cementitious material in concrete has gained attention for its potential environmental benefits. Utilizing a (5,2) simplex-lattice design, a systematic approach is employed for optimizing mixture proportions based on response parameters. The laboratory tests to evaluate concrete's mechanical behavior were conducted using the computed mixture ratios from the design experimental points after 28 days of hydration. The results showed maximum flexural strength at 8.84 N/mm2 and compressive strength at 31.16 N/mm2, achieved with a mix of 0.65:0.54:2.3:3.96:0.35 for cement, water, coarse aggregate, fine aggregate, and POFA. Additionally, maximum splitting tensile strength reached 8.84 N/mm2 with a mix of 0.62:0.55:2.09:3.86:0.38 for the same components. Conversely, the minimum flexural, splitting tensile and compressive strength within the experimental factor space was 4.25, 2.08 and 19.82 N/mm2 respectively. The results obtained indicated a satisfactory mechanical strength performance at POFA replacement of 35 percent in the concrete mixture. The developed mathematical model was statistically validated using analysis of variance (ANOVA) at a 95% confidence interval which showed satisfactory prediction performance. The findings from this study provide valuable insights into optimizing POFA-blended concrete for enhanced mechanical performance, offering potential sustainable solutions for the construction industry.

Effect of high temperature modification on the highly adsorptive manufactured sand dust concrete

The production process of manufactured sand generates a large amount of dust, which poses a serious threat to the environment. In this study, we selected highly adsorptive manufactured sand dust of three lithologies (diabase, tuff, and basalt) for high temperature calcination. We evaluated its mechanical properties and microstructures after high temperature modification using various characterization methods to investigate its feasibility as a supplementary cementitious material (SCM). A comparative analysis of the manufactured sand dust before and after modification was conducted using thermogravimetric-differential scanning calorimetry (TG-DSC), laser particle size analysis, X-ray diffraction (XRD) and X-ray fluorescence spectrometry (XRF) techniques, the results showed that high temperature modification can reduce the crystallinity of the mineral impurities in the manufactured sand dust. Furthermore, the average particle size of artificial sand dust from all three lithologies (diabase, tuff, and basalt) was reduced. However, the flowability of the mortars increased by 12.1%, 7.4%, and 6.4% respectively. The 28-day volcanic ash activity index reached 63%, 61%, and 60% respectively. In addition, we used the modified manufactured sand dust as a supplementary cementitious material in concrete. It was found that when 30% of cement was replaced with a 1:2 mixture of manufactured sand dust and fly ash, the compressive strength at 90 days reached a maximum of 90.6 MPa. These results demonstrate that the modified manufactured sand dust has certain economic benefits and can be used to partially replace cement in concrete. This provides a basis for the development and application of highly adsorptive manufactured sand in the long term.

Performance of cement-based materials incorporating ultra-fine copper slag

The application of copper slag (CS) as a supplementary cementitious material in concrete is unsatisfactory due to the fact that CS is mainly composed of fayalite. The dissolution kinetics of fayalite determines the pozzolanic activity of CS. How to improve the dissolution of fayalite is a challenge for CS resource utilization. To address this issue, ultra-fine CS with different fineness was fabricated by wet-grinding method for the first time in this work and the performance of cement-based materials incorporating ultra-fine CS was assessed. Results revealed that an increase in CS fineness significantly promoted the decomposition of fayalite to improve the mechanical strength of mortars. The 7 d and 28 d strength activity index of ultra-fine CS can reach 106% and 102%, respectively, which has seldom been reported in the literature. Although ultra-fine CS can significantly accelerate the hydration process at the very beginning of reaction to form more hydrates, the early-age pozzolanic activity was still not ideal. The prepared ultra-fine CS exhibited good later-age pozzolanic activity, which can consume more portlandite and generate more hydrates, resulting in a denser microstructure. These results indicated that ultra-fine CS can be used as a high-quality alternative cementitious material to improve the greenness of cement and concrete products.

Potential of ladle furnace slag as supplementary cementitious material in concrete

This research investigated the suitability of a locally available ladle furnace slag (LFS) as a supplementary cementitious material (SCM) to partially replace cement in concrete. The engineering properties of the LFS blended concrete were evaluated through an extensive experimental program. The SCM was used as (i) raw slag and (ii) sieved (finer than 75 µm) slag to use to produce different strength class concrete, viz., C35 and C40. Mechanical strengths and non-destructive tests were conducted for concrete with 5%, 10%, 15%, 20%, 25%, and 50% LFS replacement by weight of cement for various curing duration. Besides, indirect durability tests such as sorptivity and nitrogen gas permeability tests on LFS blended concretes were performed. Uniaxial compressive strength (UCS) for lower-grade concrete at 5% and 10% LFS levels are always higher relative to the control sample, regardless of the material type and curing period. The ultrasonic pulse velocity (UPV) test on concrete suggests that pulse velocity has a pattern similar to that of the UCS. Nitrogen gas permeability varies by LFS level, temperature, and material fineness. Capillary absorption indicates an evident general trend of increased water absorption with exposure/absorption time and LFS level. These properties for higher-grade concrete are reasonably similar to that of lower-grade concrete, however, the finer material shows better performance in this case.

Effect of calcined clay and marble dust powder as cementitious material on the mechanical properties and embodied carbon of high strength concrete by using RSM-based modelling

In the last decade, there has been an increase in research on ecologically benign, cost-effective, and socially useful cement alternative materials for concrete. Alternatives involve industrial and agriculture waste, the potential advantages of which may be recognized by recycling, repurposing, and recreating techniques. Important energy reserves and a decrease in Portland cement (PC) consumption may be attained by using these wastes as supplementary and substitute ingredients, contributing to a reduction in carbon dioxide (CO2) production. Consequently, the incorporation of marble dust powder (MDP) and calcined clay (CC) as supplementary cementitious material (SCM) in high strength concrete may lower the environmental effect and reduce the amount of PC in mixes. This study is conducted on concrete containing 0%, 5%, 10%, 15%, and 20% of MDP and CC as cementitious materials alone and in combination. The main objectives of this investigations are to examine the effect of MDP and CC as cementitious materials on the flowability and mechanical characteristics of high strength concrete. In order to examine the ecological effect of CC and MDP, the eco-strength efficiency and embodied carbon were considered. In this context, there are so many trial mixes were performed on cubical specimens for achieving targeted compressive strength about 60 MPa after 28 days. After getting it, a total of 273 concrete specimens (cubes, cylinders, and prisms) were used to test the compressive, splitting tensile, and flexural strength of high strength concrete correspondingly. Moreover, when the amount of MDP and CC as SCM in the mixture grows, the workability of green concrete decreases. In addition, the compressive strength, flexural strength, and splitting tensile strength are increased by 6.38 MPa, 67.66 MPa, and 4.88 MPa, respectively, at 10% SCM (5% MDP and 5% CC) over a period of 28 days. In addition, using ANOVA, response prediction models were generated and confirmed at a 95% level of significance. The R2 values of the models varied from 96 to 99%. Furthermore, increasing the amount of CC and MDP as SCM in concrete also reduces the amount of carbon embedded in the material. It is recommended that the utilization of 10% SCM (5% MDP and 5% CC) in high strength concrete is providing optimum outcomes for construction industry in the field of Civil Engineering.

Utilization of millet husk ash as a supplementary cementitious material in eco-friendly concrete: RSM modelling and optimization

The environment has been greatly impacted by the increase in cement consumption. However, a huge quantity of energy is consumed and large amount of poisonous gases releases into the atmosphere during the cement production, which harms the environment. In order to decrease not only cement manufacturing but also energy usage and to aid in environmental protection, scientists are attempting to introduce agricultural and industrial waste materials with cementitious characteristics. Therefore, millet husk ash is used as supplementary cementitious material (SCM) in the concrete for producing sustainable environmental. The main purpose of this investigation is to check the workability, compressive strength, splitting tensile strength, flexural strength and drying shrinkage of concrete incorporating 0 %, 5 %, 10 %, 15 % and 20 % of MHA as SCM in concrete. A total of 165 concrete samples was made with mix proportion of 1:1.5:3 and cured at ages of 7, 28, and 90 days. The investigational outcomes displayed that there was an improvement in compressive strength, tensile strength, and flexural strength by 11.39 %, 9.80 %, and 9.39 %, correspondingly, at 10 % of MHA replacement of cement. Also, the water absorption reduced as MHA content increased after 28 days. There was also a reduction in drying shrinkage of concrete as the MHA increased after 28 days. Though, the workability is declined as the proportion of MHA increased in concrete. Moreover, the embodied carbon is declined while the content of PC substituted with MHA rises in concrete. In addition, response prediction models were built and validated using ANOVA at a 95 % significance level. R2 values for the models varied from 87.47 to 99.59 percent. The study concludes that the accumulation of 10 % MHA in concrete has a favourable effect on the characteristics of the concrete.

Preparation of waste glass powder by different grinding methods and its utilization in cement-based materials

• The incorporation of ethyl alcohol was the most effective mean to refine GP. • Higher strength was exhibited in the case of specimens containing GPw and GPe. • GP showed low pozzolanic reactivity in the early age regardless of fineness. Waste glass, as a hard-to-grind material, was often grinded into powder by ball-mill in order to be used as a supplementary cementitious material in concrete. In this study, three different glass powders (GP) referred to as GPd, GPw and GPe were fabricated by different methods (i.e. dry condition, water condition and ethyl alcohol condition), and the effect of GP on the properties of cement-based materials was systematically evaluated. The results showed that the milling efficiency of GP was significantly affected by grinding condition. Ultrafine GP can be obtained as additional water or ethyl alcohol was added during the grinding process. GP showed low pozzolanic reactivity in the early age, even when the particle size was decreased to about 300 nm. GPd with large particle size and non-absorbent feature could increase effective water-to-cement ratio and thus improved the workability and early strength of specimens containing GPd, while the later strength was lower than that of reference ones due to low pozzolanic reactivity of GPd. In contrast, specimens containing GPw and GPe exhibited higher early mechanical strength than reference specimen due to the filling and acceleration effects of GP. An encouraging result indicated that GPe presented high pozzolanic reactivity at 28 d, which was seldom reported in the literature.

High strength concrete using ground granulated blast-furnace slag with Alccofine and with silica fume

High strength concrete (HSC) is highly promising building material widely used in large scale concrete constructions that require high strength, high flow ability and high durability. Several studies have been carried out in past decades to identify the use of supplementary cementitious material in concrete. To increase the durability along with strength of concrete leads to the use of high-strength concrete which is more beneficial for environmental attacks on the structure. Various studies are performed on HSC with respect to workability, strength and durability. The addition of different mineral and chemical admixtures increases the strength and durability of HSC. The effect of SCM on strength and durability of High Strength Concrete (HPC) using ground granulated blast-furnace slag (GGBS) with Alccofine and GGBS with silica fume is studied.

Lime-activation of natural pozzolan for use as supplementary cementitious material in concrete

The present work was conducted to examine the beneficial effects of activating natural pozzolan (NP) using hydrated lime (HL) for its efficient utilization in concrete. Optimum dosages of NP and HL determined based on the performance of several trial mixtures to be used in concrete as a partial replacement of ordinary Portland cement (OPC). Three mixtures were finally considered for detailed evaluation of the performance of NP-HL concrete. Activation of NP by HL increased the early- and later-age strength and decreased the depth of water penetration, coefficient of chloride diffusion, depth of carbonation, strength loss due to salt weathering, and reinforcement corrosion. Although the loss of strength due to sulfate attack and shrinkage strain increased due to the inclusion of HL, these values were less than those measured in the concrete prepared using OPC alone. In summary, the results of this study indicate that natural pozzolan can be used as a supplementary cementitious material by activating it using hydrated lime.

Rice Husk Ash (RHA) Based Concrete: Workability and Compressive Strength with Different Dosages and Curing Ages

Abstract To reduce the consumption of cement in construction industry has been a hot area of consideration now days due to high evolution of CO2 gases during its production. Since decades efforts are made to replace cement with cementitious materials; minerals, agricultural, industrial by products etc. A few are fly ash, ground granulated blast furnace slag, silica fume, rice husk ash etc. These cementitious materials are often adopted as partial replacement of cement. However, their effectiveness and suitability as cementitious material depends upon their properties and the source of the production. Pakistan is an agricultural country and one of the major crops is Rice crop. It produces a substantial amount of rice husk during the processing g of the rice. A substantial amount of Rice Husk Ash (RHA) is produced on the burning of rice husk used as fuel in the rice mills while generating steam for parboiling process of rice grains. This ash causes the environmental problems also if not dumped properly. RHA is believed to have siliceous properties which may be used as supplementary cementitious material in concrete. As the suitability of supplementary cementitious materials is dependent upon the source of rice husk, temperature of burning of husk, its fineness and other properties. This study is focused on to determine the effect of rice husk ash produced by burning of the rice husk obtained from the local rice mills. Experimental investigation carried includes the determination of workability and compressive strength of concrete with different dosage of RHA from 5% to 30% with an increment of 5% tested at 1day, 3days, 7days and 28 days of the age of concrete. The results are compared with corresponding concrete without RHA and tested at the same ages. The results show the reduction in both the parameter; workability and compressive strength due to RHA particularly at its higher dosage beyond 10% by weight of cement.

Experimental Study on the Use of Iron Tailings-Based Multicomponent Solid Waste as SCMs

A considerable amount of carbon dioxide is released during the preparation of traditional Portland cement, which is not in conformity with the sustainable road. Developing supplementary cementitious material (SCMs) and reducing cement consumption are safe ways to solve this problem. Iron tailings (IOTs), a type of mining waste from the beneficiation process of iron ore concentrate, can be used as SCMs in concrete. In order to tackle the problem of low compressive performance of IOTs as SCMs in concrete, this study develops a multi-SCMs system based on IOTs. Mechanical properties and microstructure of samples with different activator contents and ratios were analyzed by compressive strength, differential thermal–thermal gravimetric analysis (DTA-TG), and scanning electron microscopy (SEM). The results show that the compressive strength of the composite gel blocks in different gel systems changed as follows: ternary SCMs system > binary SCMs system > unary SCMs system. The ternary SCMs system (IOTs: Steel slag(SS):Phosphorus slag(PS) = 1:2:2) without activator was added so that it resulted in the highest compressive strength in multi-SCMs system. With the increase in the content of activators, the compressive strength with ternary SCMs system shows a decreasing trend. It is well known from DTA-TG, as well as SEM, that NaOH and Na2SiO3 have an inhibitory effect on the secondary hydration reaction and inhibit the formation of C-S-H gel.

Utilization of coconut shell as a supplementary cementitious material in concrete

Cement is often used as a construction material in building development. Coconut shell, on the other hand is a waste material that is the byproduct from the agricultural industry. Coconut is vastly found and utilized in most tropical countries due to the versatility of its usage. Albeit coconut shells can be used in lots of different ways, it has yet been used fully by the people. This research focuses on determining the proper percentage of partial replacement of coconut shell ash for cement in concrete. Since cement is a non-renewable material, a potential and cheaper alternative is needed to future replace the use of cement once it depletes in supply or increases in size. The characteristics of coconut shell ash (CSA) and its fresh and hardened behavior in cement and concrete will also be focused on. Methodology adopted for this research includes tests such as slump test, compressive strength test, consistency test, and fineness test. All tests were conducted within a period of 45 days and from the results gathered, it was found that 5 % of coconut shell ash as a partial replacement of cement produce the best results. Results show that the strength of the concrete will decrease when more percentage of coconut shell ash is added into the concrete mix. Therefore, the partial replacement of 5 % of coconut shell ash in concrete is the most suitable.

Mechanical, chemical and hydrothermal activation for waste glass reinforced cement

Land disposal of waste glass results in hazardous environmental contamination. Such waste material should be reclaimed because it is inert and consequently nondegradable. The main component of glass is silica showing pozzolanic properties in cementitious matrices. Thus, the use of waste glass as a supplementary cementitious material in concrete is a sustainable solution to the land disposal of such waste materials. However, concrete incorporating waste glass suffers from deleterious expansion arising from alkali-silica reaction (ASR). This paper shows the effects of different activation approaches, including mechanical, chemical, hydrothermal, and combined activation, used to mitigate ASR. To this aim, activated waste glass powder (WGP) was produced using the aforementioned approaches and used in concrete as sand replacement at percentages of 0%, 10%, 20%, and 30%. The water to cement ratio remained unchanged for all mixes. Results showed that the combined activation was the optimal approach to increase mechanical property. The hydrothermal activation effectively reduced the detrimental ASR expansion, while the chemical treatment induced excessive expansion even for mixtures with a low WGP content of 10%. Also, microstructural analyses showed erosion on the surface of WGP activated by chemical and combined activation methods. Besides, few CH crystals were observed on 75 μm WGP mortar samples, illustrating the excellent pozzolanic activity on finer WGP.

Application of Weathered Granulated Blast Furnace Slag as a Supplementary Cementitious Material in Concrete

Application of Weathered Granulated Blast Furnace Slag as a Supplementary Cementitious Material in Concrete

Development of Environment-Friendly Concrete through Partial Addition of Waste Glass Powder (WGP) as Cement Replacement

This paper presents the study carried out on the utilization of Waste Glass Powder (WGP) as supplementary cementitious material in concrete. The evaluation of the influence of WGP on the mechanical properties of concrete was carried out by casting and testing of concrete samples as per ASTM standards (cylinders and beam elements). The control samples were designed to represent field conditions with a target compressive strength of 20,000 kPa. The Portland cement in concrete was substituted with WGP in proportions of 0%-35% by weight, in increments of 5%. Two curing domains were adopted in the preparation of the test samples to evaluate the effect of pozzolanic material wherein the tested samples were cured for 28, 56, and 84 days. The study results indicated a reduction in compressive strength of concrete up to 10% with partial replacement of cement with 25% of WGP when standard curing of 28 days was adopted. Furthermore, with the same replacement proportion and prolonged curing for 84 days, the gap in strength reduction was reduced by 5%. However, a significant decrease in workability was noted between the control concrete samples and glass powder infused concrete. Furthermore, the Waste Glass Powder Concrete (WGPC) exhibited an improved flexural strength with the modulus of rupture for WGPC being 2% higher than control concrete at the age of 84 days. Based on the results of this study it was concluded that 25% replacement of cement with WGP provides an optimum replacement ratio. Doi: 10.28991/cej-2020-03091620 Full Text: PDF

Pretreatment of corn stover ash to improve its effectiveness as a supplementary cementitious material in concrete

This paper investigates the feasibility of using corn stover ash (CSA) as supplementary cementitious material to replace cement in concrete. Three types of CSA -- water-washed, acid-washed, and untreated burned corn stover -- were produced, and the influence of the pretreatment regimens on the physical and chemical properties of the produced ashes are evaluated. Moreover, the influence of CSA on the hydration kinetics of cement pastes, and compressive strength and bulk electrical resistivity of concrete specimens is discussed. The results of this study show that pretreating the corn stover before combustion increases the SiO2 content of the ash, and reduces the Cl and K2O contents, the loss on ignition, and the median particle size. The results also show that the pretreated CSA is more reactive and can accelerate the cement hydration process. Both acid- and water-washed CSA increase the strength and bulk electrical resistivity of concrete at later ages. Incorporating untreated CSA in the concrete mixture, on the other hand, reduces the compressive strength and bulk electrical resistivity of the concrete, due to the negative impacts of deleterious agents (such as high ash alkali contents) on the cement hydration process. While further work is needed, pretreated CSA could potentially be used as a novel supplementary cementitious material in concrete.

Sugarcane bagasse ash as alternate supplementary cementitious material in concrete

In this study, we examined the characteristics of sugarcane bagasse ash (SCBA) as a additional material in the mixture of concrete cubes. The additive material was collected from several sugarcane juice shop from Sathyamangalam and the bagasse get dried in sunlight for two days, sugarcane bagasse is burnt and ash is get collected and its chemical and physical properties was investigated. Sugarcane bagasse ash was replaced with cement in various proportions in the range of 5%–15% (Srinivasan and Sathiya, 2010) [1] . The SCBA mixed with cement and checked the quality tests on consistency and its time check on initial and final setting. The strength property due to compression of sugarcane bagasse ash concrete for different ratio was tested. The dumping of this material may cause environmental issues around the factories so the bagasse ash used as useful material. Therefore we decided to replace 10% in cement by sugarcane bagasse ash. The results of SCBA seem to be similar as concrete properties and replacement percentage could be increased and tested the performance of the concrete.

Red mud as an additive in concrete: comprehensive characterization

The current work investigates the sustainable use of red mud (RM) as a supplementary cementitious material in concrete. The large amount of RM produced by the alumina industry creates disposal problems, as RM pollutes the surrounding environment and leads to ecological imbalance. To develop suitable uses for RM, concrete in which some of the cement was replaced with RM was experimentally investigated. The RM content, strength, and curing age of the concrete were considered as the parameters in this work, and the mechanical properties and durability of the RM-based concrete were tested to investigate its performance. The results indicated that the RM-based concrete had superior properties. Concrete in which 10% of the cement was replaced with RM exhibited high strength and durability compared to a 100% cement-based concrete control. To examine the micro-level behavior of the RM concrete, the microstructure was studied using X-ray diffraction and scanning electron microscopy.