scholarly journals Response Surfaces for Fresh and Hardened Properties of Concrete with E-Waste (HIPS)

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
K. Senthil Kumar ◽  
K. Baskar
Keyword(s):  
Response Surface ◽  
Coarse Aggregate ◽  
Response Surfaces ◽  
Partial Replacement ◽  
Contour Plot ◽  
Dry Density ◽  
Waste Plastic ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Hardened Properties

The fresh and hardened properties of concrete with E-waste plastic, that is, high impact polystyrene (HIPS), as a partial replacement for coarse aggregate were analyzed using response surface methodology (RSM). Face-centred central composite response surface design was used in this study. The statistical models were developed between the factors (HIPS and water cement ratio) and their response variables (slump, fresh density, dry density, compressive strength, spilt tensile strength, and flexural strength). The Design-Expert 9.0.3 software package was used to analyze the experimental values. The relationships were established and final mathematical models in terms of coded factors from predicted responses were developed. The effects of factors on properties for all variables were seen visually from the response surface and contour plot. Validation of experiments has shown that the experimental value closely agreed with the predicted value, which validates the calculated response surface models with desirability = 1. The HIPS replacement influenced all the properties of concrete than water cement ratio. Even though all properties show the decline trend, the experimented values and predicted values give a hope that the E-waste plastic (HIPS) can be used as coarse aggregate up to certain percentage of replacement in concrete which successively reduces the hazardous solid waste problem and conserves the natural resources from exhaustion.

Effect of Substitution of Crushed Waste Glass as Partial Replacement for Natural Fine and Coarse Aggregate in Concrete

2016 ◽  
Vol 866 ◽  
pp. 58-62 ◽  
Author(s):  
Oluwarotimi M. Olofinnade ◽  
Julius M. Ndambuki ◽  
Anthony N. Ede ◽  
David O. Olukanni
Keyword(s):  
Coarse Aggregate ◽  
Waste Glass ◽  
Glass Content ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Fine Aggregate ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Concrete Production ◽  
Concrete Mix

Reusing of waste glass in concrete production is among the attractive option of achieving waste reduction and preserving the natural resources from further depletion thereby protecting the environment and achieving sustainability. This present study examines the possible reuse of waste glass crushed into fine and coarse aggregate sizes as partial substitute for natural fine and coarse aggregate in concrete. The variables in this study is both the fine and coarse aggregate while the cement and water-cement ratio were held constant. The crushed glass was varied from 0 – 100% in steps of 25% by weight to replace the both the natural fine and coarse aggregate in the same concrete mix. Concrete mixes were prepared using a mix proportion of 1:2:4 (cement: fine aggregate: coarse aggregate) at water-cement ratio of 0.5 targeting a design strength of 20 MPa. Tests were carried out on total number of 90 concrete cube specimens of size 150 x 150 x150 mm and 90concrete cylinder specimens of dimension 100 mm diameter by 200 mm height after 3, 7, 14, 28, 42 and 90 days of curing. Test results indicated that the compressive and split tensile strength of the hardened concrete decreases with increasing waste glass content compared with the control. However, concrete mix made with 25% waste glass content compared significantly well with the control and can be suitably adopted for production of light weight concrete.

Impact of Partial Replacement of Brick Coarse Aggregate by Waste Rubber Tyre on the Fresh and Hardened Properties of Concrete

2021 ◽  
Vol 877 ◽  
pp. 131-137
Author(s):  
Md Jihad Miah ◽  
Md Kawsar Ali ◽  
Suvash Chandra Paul ◽  
Mohammad Shamim Miah ◽  
M. M. Haque ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Coarse Aggregate ◽  
Tap Water ◽  
Partial Replacement ◽  
Dry Density ◽  
Waste Rubber ◽  
Maximum Decrease ◽  
Hardened Properties ◽  
Rubber Aggregates

This study focused on the feasibility of utilizing waste rubber tyre as coarse aggregate in concrete as a partial replacement of brick aggregate (BA). Within this context, fresh and hardened properties were investigated on concrete made with three different percentage replacements (0, 10 and 20% by volume) of BA by waste rubber tyre aggregate (WRTA). The WRTA was washed with tap water (H2O) and treated with 20% sodium hydroxide (NaOH) for 2 hours. It was found that the workability and dry density of concrete decrease with an increasing percentage of WRTA. In case of mechanical properties, the compressive strength decreases with the increasing content of both treated and untreated WRTA. The maximum decrease was observed for 20% of both treated and untreated WRTA, which was 41-46% for treated and 47-54% for untreated lower than the reference concrete for all curing ages. It was observed that the concrete made with tyre treated with NaOH provides better strength than untreated tyre aggregate. This behavior could be attributed to the better bonding between cement paste and rubber aggregates as a result of the increased surface roughness by NaOH.

scholarly journals Performance Evaluation of Plastic Concrete Modified with E-Waste Plastic as a Partial Replacement of Coarse Aggregate

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 175
Author(s):  
Farhan Ahmad ◽  
Arshad Jamal ◽  
Khwaja Mateen Mazher ◽  
Waleed Umer ◽  
Mudassir Iqbal
Keyword(s):  
Coarse Aggregate ◽  
Electronic Waste ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Partial Replacement ◽  
Dry Density ◽  
Waste Plastic ◽  
Significant Decrement ◽  
The World

Plastic electronic waste (E-waste) is constantly growing around the world owing to the rapid increase in industrialization, urbanization, and population. The current annual production rate of E-waste is 3–4% in the world and is expected to increase to 55 million tons per year by 2025. To reduce the detrimental impact on the environment and save natural resources, one of the best solutions is to incorporate waste plastic in the construction industry to produce green concrete. This study examines the use of manufactured plastic coarse aggregate (PCA) obtained from E-waste as a partial replacement of natural coarse aggregate (NCA) in concrete. Six types of concrete mix with 10%, 20%, 30%, 40%, and 50% substitution of NCA (by volume) with PCA are prepared and tested. This study investigates the effect of manufactured PCA on the fresh and hardened characteristics of concrete. The properties of recycled plastic aggregate concrete (RPAC) studied include workability, fresh density, dry density, compressive strength (CS), splitting tensile strength (STS), flexural strength (FS), sorptivity coefficient, abrasion resistance, ultrasonic pulse velocity (UPV), and alternate wetting and drying (W–D). The results indicate that the CS, STS, and FS of RPAC declined in the range of 9.9–52.7%, 7.8–47.5%, and 11–39.4%, respectively, for substitution ratios of 10–50%. However, the results also indicate that the incorporation of PCA (10–50%) improved the workability and durability characteristics of concrete. A significant decrement in the sorptivity coefficient, abrasion loss, and UPV value was observed with an increasing amount of PCA. Furthermore, RPAC containing different percentages of PCA revealed better results against alternate W–D cycles with respect to ordinary concrete.

scholarly journals Effect of Water Cement Ratios on Compressive Strength of Palm Kernel Shell Concrete

2019 ◽  
Vol 2 (Issue 1) ◽  
Author(s):  
A.O Adeyemi ◽  
M.A Anifowose ◽  
I.O Amototo ◽  
S.A Adebara ◽  
M.Y Olawuyi
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Fresh Concrete ◽  
Palm Kernel ◽  
Hardened Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Palm Kernel Shell ◽  
Compressive Strength Of Concrete ◽  
Palm Kernel Shells

This study examined the effect of varying water cement ratio on the compressive strength of concrete produced using palm kernel shell (PKS) as coarse aggregate at different replacement levels. The replacement levels of coarse aggregate with palm kernel shells (PKS) were 0%, 25%, 50%, and 100% respectively. PKS concrete cubes (144 specimens) of sizes 150mm x 150mm x 150mm were cast and cured in water for 7, 14, 21 and 28 days respectively. A mix ratio of 1:2:4 was adopted with water-cement ratio of 0.45, 0.5, and 0.6 respectively while the batching was done by weight. Slump test was conducted on fresh concrete while compressive strength test was carried out on the hardened concrete cubes using a compression testing machine of 2000kN capacity. The result of tests on fresh concrete shows that the slump height of 0.45 water cement ratio (w/c) increases with an increase in PKS%. This trend was similar to 0.50 and 0.60 w/c. However, the compressive strength of concrete cube decreases with an increase in w/c (from 0.45 to 0.60) but increases with respect to curing age and also decreases with increase in PKS%. Concrete with 0.45 water-cement ratio possess the highest compressive strength. It was observed that PKS is not a good substitute for coarse aggregate in mix ratio 1:2:4 for concrete productions. Hence, the study suggest the use of chemical admixture such as superplasticizer or calcium chloride in order to improve the strength of palm kernel shells-concrete.

scholarly journals The Influence of Finely Ground Mineral Admixture (FGMA) on Efflorescence

2013 ◽  
Vol 4 (1) ◽  
pp. 50-55 ◽  
Author(s):  
Ong Ming Wei ◽  
Norsuzailina Mohamed Sutan
Keyword(s):  
Calcium Carbonate ◽  
Chemical Analysis ◽  
Mineral Admixture ◽  
Partial Replacement ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Cement Replacement ◽  
Carbonate Formation

Efflorescence phenomenon on concrete is not new and found in the form of white deposits on surfaces of concrete. Incorporation of Finely Ground Mineral Admixture (FGMA) in concrete to prevent occurrence of efflorescence is based on reduction of portlandite, densified microstructure and thus enhanced watertightness. The magnitude of efflorescence in term of percentage of calcium carbonate formation of FGMA modified mortar were evaluated at water-cement ratio of 0.3, 0.4 and 0.5 with 10%, 20%, and 30% of cement replacement by weight. The samples were tested with chemical analysis at 7, 14, 21, 28, 60 and 90 days. The FGMA additions into mortar were comparing with ordinary mortar to evaluate enhanced performance of FGMA modified mortar toward efflorescence. The results of this experiment showed that addition of FGMA into mortar caused less formation of calcium carbonate as partial replacement of cement with certain w/c ratio and percentage of cement replacement.

Revised Method for Rapid Determination of On-Site Water–Cement Ratio using Microwave Oven

2019 ◽  
Vol 2673 (8) ◽  
pp. 1-10
Author(s):  
Seyednavid Mardmomen ◽  
Hung-Liang (Roger) Chen ◽  
Guadalupe Leon
Keyword(s):  
Coarse Aggregate ◽  
Fresh Concrete ◽  
Rapid Determination ◽  
Microwave Oven ◽  
Cementitious Material ◽  
Percentage Error ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Average Percentage ◽  
Site Water

The water–cement ratio (w/c) of delivered concrete is one of the most important parameters of the material’s quality. In this study, the AASHTO T318-15 guideline was adopted to estimate the water content of fresh concrete mixes and was revised for better precision. The additional step required sieving out the coarse aggregate after drying the sample in a microwave oven, and using it in the calculation of the absorbed water and cementitious material content. The cementitious content was assumed to be proportional to the mix design ratios. Several laboratory batches, as well as on-site water–cementitious material (w/cm) ratio tests, were performed on concrete mixes containing ordinary Portland cement, ground-granulated blast furnace slag, and Class F fly ash. The results of the experiments indicated the accuracy of the revised method was increased to have an average percentage error of about 2.16% from the actual w/cm ratio whereas the method based on AASHTO calculations was 6.2%. For cases with high chemical admixture dosages, washing vinegar was used to wash out the particles around the dried sieved coarse aggregate to calculate the w/cm ratio with a more precise mass for each sample. The correlation between the measured and calculated compressive strength using the measured amount of w/cm ratios provides evidence for the method’s accuracy. Therefore, the revised method can be used as an accurate and practical process of measuring the on-site w/cm ratios of fresh concrete mixes.

scholarly journals Effect of Phenolic Particles on Mechanical and Thermal Conductivity of Foamed Sulphoaluminate Cement-Based Materials

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3596 ◽  
Author(s):  
Xiuzhi Zhang ◽  
Qing Yang ◽  
Qinfei Li ◽  
Heng Chen ◽  
Guofa Zheng ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Pore Structure ◽  
Dry Density ◽  
Mechanical And Thermal Properties ◽  
Foaming Agent ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Performance Indexes ◽  
Foamed Concrete ◽  
Inorganic Matrix

Foamed concrete materials based on sulpoaluminate cement were prepared by the chemical foaming method. The effects of water–cement ratio, foaming agent, and foaming stabilizer on the mechanical and thermal properties of foamed concrete were studied. Meanwhile, a portion of cement was replaced with foamed phenolic particles to further optimize the performance of foamed concrete; the results show that when the water–cement ratio was 0.53, the foaming agent content was 5%, the foam stabilizer was 1%, and the substitution of phenolic particles was 20%, the performance indexes of foamed concrete were the best. Methods, describing briefly the main methods or treatments applied: dry density was 278.4 kg/m3, water absorption was 19.9%, compressive strength was 3.01 MPa, and thermal conductivity was 0.072 W/(m·K). By the pore structure analysis of the foamed concrete suing Micro-CT, it was found that when the replacement amount of phenolic particles was 20%, the pore size of foamed concrete was relatively uniform, the minimum D90 was 225 μm respectively. The combination of organic and inorganic matrix and optimized pore structure improved the performance of foamed concrete.

scholarly journals Use of Recycled Tyre Rubber in Non-structural Concrete

2018 ◽  
Vol 203 ◽  
pp. 06001
Author(s):  
Muhammad Bilal Waris ◽  
Hussain Najwani ◽  
Khalifa Al-Jabri ◽  
Abdullah Al-Saidy
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Coarse Aggregate ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Structural Concrete ◽  
Cement Ratio ◽  
Mix Proportion ◽  
Water To Cement Ratio ◽  
Concrete Blocks

To manage tyre waste and conserve natural aggregate resource, this research investigates the use of waste tyre rubber as partial replacement of fine aggregates in non-structural concrete. The research used Taguchi method to study the influence of mix proportion, water-to-cement ratio and tyre rubber replacement percentage on concrete. Nine mixes were prepared with mix proportion of 1:2:4, 1:5:4 and 1:2.5:3; water-to-cement ratio of 0.25, 0.35 and 0.40 and rubber to fine aggregate replacement of 20%, 30% and 40%. Compressive strength and water absorption tests were carried out on 100 mm cubes. Compressive strength was directly proportional to the amount of coarse aggregate in the mix. Water-to-cement ratio increased the strength within the range used in the study. Strength was found to be more sensitive to the overall rubber content than the replacement ratio. Seven out of the nine mixes satisfied the minimum strength requirement for concrete blocks set by ASTM. Water absorption and density for all mixes satisfied the limits applicable for concrete blocks. The study indicates that mix proportions with fine to coarse aggregate ratio of less than 1.0 and w/c ratio around 0.40 can be used with tyre rubber replacements of up to 30 % to satisfy requirements for non-structural concrete.

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