scholarly journals Water Requirement of Concrete with Mineral Admixtures

2021 ◽  
Vol 9 (VI) ◽  
pp. 4573-4577
Author(s):  
Alka A. Avasthi
Keyword(s):  
Particle Size ◽  
Water Content ◽  
Surface Area ◽  
Agricultural Waste ◽  
Water Requirement ◽  
Mineral Admixtures ◽  
Partial Replacement ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Cement Replacement

India is one of the leading producers of sugar and rice, hence agricultural waste is generated in huge quantities in India leading to potential disposal problems without effective management techniques. However, the economic importance of this solid waste has been realised with several applications like adsorbents, filters, ceramics, briquettes, bricks, and blocks and soil amendment activities. Cement is one of the most universally used material. Cement production is an environmental threat as well as the production cost is also very high. Manufacturing of cement and its use is also one of the causes of global warming Environmentalists and Researchers around the world are searching for better options to replace cement As cement replacement materials mineral admixtures are nowadays gaining mileage as they address two problems. First is the waste management of agricultural wastes, which causes air pollution due to open air burning and the second is reducing the demand for cement. Hence in addition to reducing the cost it also reduces the hazardous effect that it has on the environment. In general, the particle size of these admixtures play an important role in making the concrete dense, but low particle size leads to increased surface area and more requirement their surface area increases and workability reduces. Hence to make the concrete workable the water requirement also increase [1].Generally the water requirement or the water cement ratio for normal concrete is between 0.35 to 0.5 , depending on the cement content and the mix design . For high strength concrete where the quantity of cement increases the water cement ratio also increases. But in concrete with mineral admixtures the water cement ratio is more than 0.6. The present paper deals with the water requirement for the concrete with cement replacement with mineral admixtures , The two types of admixtures water requirement of concrete with partial replacement of cement with sugarcane bagasse ash and rice husk ash in different proportions of 5 % , 10%, 15% , 20%, 25% and 30 % , earlier as a binary mix replacing the mineral admixtures individually and later together as a ternary mix using both the mineral admixtures together. The results indicate increase in water content with the increase in cement replacement proportions in both the binary and ternary mix . The increase in water content does not hamper the compressive strength of the binary and ternary mix , but in some cases increases it.

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.

Research Progress on Early Autogenous Shrinkage of Cement-Based Cementitious Materials

2013 ◽  
Vol 634-638 ◽  
pp. 2738-2741
Author(s):  
Wei Huang ◽  
Tao Zhang ◽  
Yun Yun Xu
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Research Work ◽  
Autogenous Shrinkage ◽  
Cementitious Materials ◽  
Mineral Admixtures ◽  
Research Progress ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Improvement Measures

Concrete autogenous shrinkage phenomenon would adversely affect the mechanical properties and durability of concrete, this phenomenon is important. Autogenous shrinkage problem of low water-cement ratio of the with high mineral admixtures, cement-based cementitious materials was introduced. The main reason for high-performance concrete early cracking being autogenous shrinkage was pointed out. Based on the home and abroad research status of low water cement ratio of the cement paste and concrete autogenous shrinkage, especially for early autogenous shrinkage phenomenon, the mechanism of autogenous shrinkage and the measure method is presented, and the improvement measures and the possible problems the need for further research work is presented.

Evaluation of initial setting time due to superplasticizers

2017 ◽  
Vol 8 (2) ◽  
pp. 65
Author(s):  
Abhishek Singh ◽  
Shobha Ram ◽  
Alok Verma
Keyword(s):  
Water Content ◽  
Cement Paste ◽  
Setting Time ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Initial Setting Time ◽  
Initial Setting

This paper shows how polycarboxylate based superplasticizer affects the initial setting time of cement paste. Three superplasticizers are used in this study with different properties and aiming to determine the delay in initial setting time due to superplasticizer. Initial setting time is calculated as per IS: 4031-PART 5-1988 with different SP dosages (0.5%, 0.75%, 1.0% and 1.5% of weight of cement). Superplasticizer is an admixture which reduces the water-cement ratio or increase the workability at the same water content. This paper deals with the evaluation of initial setting time due to superplasticizers.

scholarly journals SUITABILITY OF BURNT AND CRUSHED COW BONES AS PARTIAL REPLACEMENT FOR FINE AGGREGATE IN CONCRETE

2017 ◽  
Vol 36 (3) ◽  
pp. 686-690
Author(s):  
NM Ogarekpe ◽  
JC Agunwamba ◽  
FO Idagu ◽  
ES Bejor ◽  
OE Eteng ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Fine Aggregates ◽  
Concrete Mix ◽  
Average Compressive Strength ◽  
Curing Age

The suitability of burnt and crushed cow bones (BCCB) as partial replacement for fine aggregate in concrete was studied. The percentages of replacements of fine aggregates of 0, 10, 20, 30, 40 and 50%, respectively of BCCB were tested considering 1: 2: 4 and 1: 11/2 :3 concrete mix ratios. The cow bones were burnt for 50 minutes up to 92oC before being crushed. Ninety-six (96) concrete cubes of 1: 2: 4 mix ratio and ninety-six (96) concrete cubes of 1 : : 3 mix ratio measuring 150x150x150mm were tested for the compressive strength at 7, 14, 21 and 28 days respectively. The research revealed that the BCCB acted as a retarder in the concrete. Water-cement ratio increased with the increase in the percentage of the BCCB. The mixes of 1:2:4 and 1::3 at 28 days curing yielded average compressive strengths in N/mm2 ranging from 16.49 - 24.29 and 18.71 - 29.73, respectively. For the mix ratios of 1:2:4 and 1:: 3 at 28 days curing age,  it was observed that increase in the BCCB content beyond 40 and 50%, respectively resulted to the reduction of the average compressive strength below recommended minimum strength for use of concrete in structural works.http://dx.doi.org/10.4314/njt.v36i3.4

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.

scholarly journals Experimental Study on Groutability of Sand Layer concerning Permeation Grouting

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yan-Xu Guo ◽  
Qing-Song Zhang ◽  
Lian-Zhen Zhang ◽  
Ren-Tai Liu ◽  
Xin Chen ◽  
...  
Keyword(s):  
Particle Size ◽  
Relative Density ◽  
Clay Content ◽  
Sand Particle ◽  
Sand Layer ◽  
Permeation Grouting ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Grouting Pressure ◽  
Relative Density Of Sand

Permeation grouting is widely used in grouting engineering because of its low grouting pressure and minor disturbance to the stratum. However, influenced by the complex properties of sand layer and slurry, an accurate prediction of the groutability of the sand layer remains to be a hard work. In this paper, the permeability of sand layer is studied based on a self-designed permeation grouting test device, which considers the different sand particle size, relative density of sand layer, slurry water-cement ratio, and clay content. The influencing factors of sand layer groutability are analyzed, and the different parameters that affect the grouting of sand layer are evaluated, thus proposing a new approach to predict the groutability of sand layer. Results show that the sand particle size and slurry water-cement ratio are positively related to the groutability of sand layer, and the relative density and clay content of sand layer are negatively correlated with the groutability of sand layer. The proposed alternative empirical formula to estimate the groutability of sand layer will help predict the groutability of sand layer with a higher degree of accuracy, which can provide a certain reference for engineering.

scholarly journals Chicken Feather Ash (CFA) as a Partial Replacement of Cement in Concrete

2021 ◽  
pp. 130-140
Author(s):  
Victor Emeka Amah ◽  
Ejikeme Ugwoha ◽  
Jahswill Macaulay
Keyword(s):  
Compressive Strength ◽  
Partial Replacement ◽  
Chicken Feather ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Chicken Feathers ◽  
Allowable Range ◽  
Full Factorial ◽  
Optimum Water ◽  
Curing Age

Every day, large quantities of chicken feathers are disposed of as waste at markets where birds are slaughtered and sold for meat. The possibility of using Chicken feather ash (CFA) as a partial replacement of cement in the concrete making was investigated. Water-cement ratio and percentage CFA used for replacement were chosen as variables in the design of the experiment. Compressive strength and workability were chosen as the required responses to observe and analyzed using response surface methodology. Full factorial design was used for the design of experiment, with CFA replacement and water-cement ratio ranging from 2 – 11% and 0.3 – 0.7 % by mass respectively. There were 27 trial mixes and the freshly made concrete mix was tested for workability. Concrete cubes were molded and cured for 7 and 14 days and were crushed to determine the compressive strength. It was found that as the CFA percentage increases, the workability of the concrete increases making it more fluid. The optimum water-cement ratio was observed to range from 0.49 to 0.51 % as the curing age increases. The optimum compressive strength was observed to range from 15.6 to 18.6 N/mm2 as the curing age increased. However, the allowable range of CFA to be used for concrete making is 3.8 to 6.34 % beyond which compressive strength reduces.

scholarly journals Strength Characteristics of Groundnut Leaf/Stem Ash (GLSA) Concrete

2016 ◽  
Vol 24 (3) ◽  
pp. 36-43
Author(s):  
O. W. Oseni ◽  
M. T. Audu
Keyword(s):  
Compressive Strength ◽  
Strength Properties ◽  
Strength Characteristics ◽  
Partial Replacement ◽  
Structural Elements ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Coarse Aggregates ◽  
Flow Test ◽  
Pozzolanic Properties

Abstract The compressive strength properties of concrete are substantial factors in the design and construction of concrete structures. Compressive strength directly affects the degree to which the concrete can be able to carry a load over time. These changes are complemented by deflections, cracks etc., in the structural elements of concrete. This research investigated the effect of groundnut leaf/stem ash (GLSA) on the compressive strength of concrete at 0%, 5 %, 10 % and 15 % replacements of cement. The effect of the water-cement ratio on properties such as the compressive strength, slump, flow and workability properties of groundnut leaf/stem ash (GLSA) mixes with OPC were evaluated to determine whether they are acceptable for use in concrete structural elements. A normal concrete mix with cement at 100 % (i.e., GLSA at 0%) with concrete grade C25 that can attain an average strength of 25 N/mm2 at 28 days was used as a control at design water-cement ratios of 0.65 and grading of (0.5-32) mm from fine to coarse aggregates was tested for: (1) compressive strength, and the (2) slump and flow Test. The results and observations showed that the concrete mixes from GLSA at 5 – 15 % ratios exhibit: pozzolanic properties and GLSA could be used as a partial replacement for cement at these percentage mix ratios compared with the control concrete; an increase in the water-cement ratio showed a significant decrease in the compressive strength and an increase in workability. Therefore, it is important that all concrete mixes exude an acceptably designed water-cement ratio for compressive strength characteristics for use in structures, water-cement ratio is a significant factor.

scholarly journals Influence of cement replacement with limestone filler on the properties of concrete

2021 ◽  
Vol 64 (3) ◽  
pp. 165-170
Author(s):  
Ksenija Tešić ◽  
Snežana Marinković ◽  
Aleksandar Savić
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Mineralogical Composition ◽  
Limestone Filler ◽  
Green Concrete ◽  
Cement Ratio ◽  
Cement Replacement ◽  
Concrete Mixtures ◽  
Water To Cement Ratio ◽  
Compressive Strength Of Concrete

This paper presents an experimental research of one type of green concrete in which Portland cement was replaced with two types of limestone filler of the same origin and mineralogical composition, but with a different fineness of particles. Ten concrete mixtures were designed in which 0%, 15%, 30% and 45% (by mass) of cement were replaced with filler. The water to cement ratio for each mixture was constant (w/c=0.54), and the water to powder ratio was decreasing with increasing cement replacement. Particle size distribution was selected using Funk and Dinger, as well as using Fuller's model. The results showed that it is possible to increase the compressive strength of concrete by reducing 45% of cement, but further research should be focused on improving the workability.

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