scholarly journals An experimental study on production of high strength non-shrink grout containing fly ash

2021 ◽  
Vol 72 (4) ◽  
pp. 477-485
Author(s):  
Chi Dang Thuy
Keyword(s):  
Experimental Study ◽  
Compressive Strength ◽  
Fly Ash ◽  
Drying Shrinkage ◽  
High Strength ◽  
Fine Aggregate ◽  
Expansive Agent ◽  
Chemical Admixture ◽  
The University ◽  
The Given

Cement-based grouts are widely used thanks to its outstanding features such as high workability, non-separation, non-bleeding, easy to fulfill small gaps with complex shapes. This paper descrcibes the first phase of a series of laboratory experiments that examined the ability of production of self - levelling mortar at the University of Transport and Communications. The Portland cement-based grout incorporated superplasticizer, fly ash, fine aggregate, water along with expansion agent to match as closed as possible the given high strength non-shrink grout. The experimental study focused on the performance of non-shrink grouts regarding the flowability, expansion and bleeding, strengths and drying shrinkage of the test grout mixtures. The high range water reducer (HRWR) at dosage of 1% by weight of cement was used as a flowability modifying chemical admixture to prevent water segregation and leads to an increase in compressive strength. The parameter tests consist of water-cement ratios, and fixed dosages of superplasticizer and expansive agent. To examine the flowability of grout mortars, the flow cone test was applied. The flow cone test result indicated that there were three proportional of grouts that can meet the requirement of fluidity. The compressive strength of specimens was tested according to ASTM C349-14. It was concluded that the compositions of grouts at a water-cement ratio of from 0.29 to 0.33 have compressive strengths greater than 60 MPa. The tested specimens using the expansive agent with the dosage recommended by the manufacturer meet the non-shrinkage requirement of a grout. The experimental results have demonstrated the ability of production of high strength non-shrink grouts.

scholarly journals Experimental study on the properties of highperformance concrete made with class C fly ash

2019 ◽  
Vol 276 ◽  
pp. 01014
Author(s):  
I Made Alit Karyawan Salain ◽  
I Nyoman Sutarja ◽  
Teguh Arifmawan Sudhiarta
Keyword(s):  
Experimental Study ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Fly Ash ◽  
Permeability Coefficient ◽  
Splitting Tensile Strength ◽  
Type I ◽  
Fine Aggregate ◽  
Hydration Time ◽  
Class C

This experimental study presents the properties of highperformance concrete (HPC) made by partially replacing type I Portland cement (OPC) with class C fly ash (CFA). The purpose of this study is to examine, with hydration time, the development of the compressive strength, the splitting tensile strength and the permeability of HPC utilizing different quantity of CFA. Four HPC mixtures, C1, C2, C3, and C4, were made by utilizing respectively 10%, 20%, 30% and 40% of CFA as replacement of OPC, by weight. One control mixture, C0, was made with 0% CFA. The mix proportion of HPC was 1.00 binder: 1.67 fine aggregate: 2.15 coarse aggregate with water to binder ratio 0.32. In each mixture, it was added 5% silica fume and 0.6% superplasticizer of the weight of the binder. Tests of HPC properties were realized at the age of 1, 3, 7, 28, and 90 days. The results indicate that CFA used to partially replace OPC in HPC shows adequate cementitious and pozzolanic properties. The compressive strength and the splitting tensile strength of HPC increase while the permeability coefficient decreases with increasing hydration time. It is found that the optimum replacement of OPC with CFA is 10%, however the replacement up to 20% is still acceptable to produce HPC having practically similar harden properties with control mixture. At this optimum replacement and after 90 days of hydration, the compressive strength, the splitting tensile strength and the permeability coefficient can reach 68.9 MPa, 8.3 MPa and 4.6 E-11 cm/sec respectively. These results are 109%, 101%, and 48% respectively of those of control mixture.

Water Penetration Resistance of Fly Ash Concrete Incorporating with Quarry Wastes

2017 ◽  
Vol 886 ◽  
pp. 159-163 ◽  
Author(s):  
Suppachai Sinthaworn
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
High Strength ◽  
Cementitious Materials ◽  
Fine Aggregate ◽  
Water Penetration ◽  
Strength Concrete ◽  
Fly Ash Concrete ◽  
Suitable Amount ◽  
Normal Strength

Slump of fresh concrete, compressive strength and water penetration depth under pressure of fly ash concrete incorporate with quarry waste as fine aggregate were investigated. The cementitious materials of the concrete includes ordinary Portland cement 80% and fly ash 20% by weight of cementitious. The mix proportions of the concrete were set into two classes of compressive strength. The results show that fly ash enhances workability of both concretes (normal concrete and concrete incorporate with quarry waste). Increasing the percentage of quarry dusts as fine aggregate in concrete seem negligible effect on the compressive strength whereas adding fly ash shows a slightly improve the compressive strength in the case of cohesive concrete mixture. Besides, adding the suitable amount of fly ash could improve the permeability of concrete. Therefore, fly ash could be a good admixture to improve the water resistant of normal strength concrete and also could be a supplemental material to improve the compressive strength of normal high strength concrete.

scholarly journals Strength Determination of High Strength Concrete Blended with Copper Slag and Fly Ash

2021 ◽  
Vol 9 (VII) ◽  
pp. 1198-1203
Author(s):  
Jamshed Alam
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
High Strength Concrete ◽  
Free Water ◽  
High Strength ◽  
Copper Slag ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Strength Concrete ◽  
Free Water Content

An experimental analysis was conducted to study the effects of using copper slag as a fine aggregate (FA) and the effect of fly ash as partial replacement of cement on the properties high strength concrete. In this analysis total ten concrete mixtures were prepared, out of which five mixes containing different proportions of copper slag ranging from 0% (for the control mix) to 75% were prepared and remaining five mixes containing fly ash as partial replacement of cement ranging from 6% to 30% (all mixes contains 50% copper slag as sand replacements). Concrete matrix were tested for compressive strength, tensile strength and flexural strength tests. Addition of copper slag as sand replacement up to 50% yielded comparable strength with that of the control matrix. However, further additions of copper slag, caused reduction in strength due to an increment of the free water content in the mix. Concrete mix with 75% copper slag replacement gave the lowest compressive strength value of approximately 80 MPa at 28 days curing period, which is almost 4% more than the strength of the control mix. For this concrete containing 50% copper slag, fly ash is introduced in the concrete to achieve the better compressive, split and flexural strengths. It was also observed that, introduction of the fly ash gave better results than concrete containing 50% copper slag. When concrete prepared with 18 % of fly ash, the strength has increased approximately 4%, and strength decreased with further replacements of the cement with fly ash. Hence, it is suggested that 50% of copper slag can be used as replacement of sand and 18% fly ash can be used as replacement of cement in order to obtain high strength concrete.

scholarly journals Predicting the drying shrinkage behavior of high strength portland cement mortar under the combined influence of fine aggregate and steel micro fiber

2017 ◽  
Vol 67 (326) ◽  
pp. 119 ◽  
Author(s):  
Zhengqi Li
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Cement Mortar ◽  
Drying Shrinkage ◽  
High Strength ◽  
Fiber Content ◽  
Fine Aggregate ◽  
Aggregate Content ◽  
Normal Strength ◽  
Gardner Model

The workability, 28-day compressive strength and free drying shrinkage of a very high strength (121-142 MPa) steel micro fiber reinforced portland cement mortar were studied under a combined influence of fine aggregate content and fiber content. The test results showed that an increase in the fine aggregate content resulted in decreases in the workability, 28-day compressive strength and drying shrinkage of mortar at a fixed fiber content. An increase in the fiber content resulted in decreases in the workability and drying shrinkage of mortar, but an increase in the 28-day compressive strength of mortar at a fixed fine aggregate content. The modified Gardner model most accurately predicted the drying shrinkage development of the high strength mortars, followed by the Ross model and the ACI 209R-92 model. The Gardner model gave the least accurate prediction for it was developed based on a database of normal strength concrete.

MECHANICAL PROPERTIES AND SHRINKAGE PROPERTIES OF THE CONCRETE WITH RECYCLED FINE AGGREGATE AND ADMIXTURE

2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Yuji Nakata ◽  
Koji Takasu ◽  
Hidehiro Koyamada ◽  
Hiroki Suyama
Keyword(s):  
Compressive Strength ◽  
Pore Volume ◽  
Drying Shrinkage ◽  
High Strength ◽  
Recycled Aggregate ◽  
Fine Aggregate ◽  
Shrinkage Ratio ◽  
Recycled Fine Aggregate ◽  
High Durability ◽  
The Relationship

In Japan, it is forecasted that massive amounts of concrete waste material will be generated in the future as a result of demolition of many buildings, and expansion of the use of recycled aggregate is expected. In this study, it was verified the effect when relatively large amount of admixture is mixed, a combination of recycled fine aggregate of different quality and various admixtures, combination of each admixture in order to realize high strength and high durability by using recycled aggregate. The increase in the drying shrinkage ratio due to the deterioration of the recycled fine aggregate quality was larger than the fluctuation due to the admixture mixing ratio and the drying shrinkage ratio was distributed by forming a group for each quality of recycled fine aggregate. In the relationship between the pore volume and the compressive strength, when evaluated with pore volume of 2 μm or less in both cases, a good linear relationship could be confirmed. The relationship between the pore volume and the drying shrinkage rate was similar. Therefore, it was suggested that compressive strength and drying shrinkage ratio of mortar contained composite recycled fine aggregate and admixture could be predicted by evaluating with the pore volume of 2 μm or less.

scholarly journals Experimental Study on Forecasting Mathematical Model of Drying Shrinkage of Recycled Aggregate Concrete

2012 ◽  
Vol 2012 ◽  
pp. 1-14
Author(s):  
Yuanchen Guo ◽  
Xue Wang
Keyword(s):  
Mathematical Model ◽  
Experimental Study ◽  
Fly Ash ◽  
Drying Shrinkage ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Drying Time ◽  
Aggregate Concrete ◽  
Expansive Agent ◽  
Basic Law

On the basis of basic law in AASHTO2007 model, the forecasting mathematical model of drying shrinkage of recycled aggregate concrete (RAC) is established by regression analysis and experimental study. The research results show that (1) with the replacement rate of RCA increases, the drying shrinkage value of RAC increases; this trend is even more obvious in the early drying time. (2) The addition of fly ash can inhibit the drying shrinkage of RAC, but the effect is not very obvious. Specifically, the addition of fly ash will increase the shrinkage to some extent when the mixing amount is 20%. (3) The addition of expansive agent can obviously inhibit the shrinkage of RAC; the inhibition affection is better than that of fly ash. (4) The forecasting mathematical models of drying shrinkage of RAC established in this paper have high accuracy and rationality according to experiment validation and error analysis.

Investigation on a New Hydraulic Cementitious Binder Made from Phosphogypsum

2013 ◽  
Vol 864-867 ◽  
pp. 1923-1928
Author(s):  
Yue Xu ◽  
Jian Xi Li ◽  
Li Li Kan
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Active Carbon ◽  
High Strength ◽  
Tricalcium Silicate ◽  
Dicalcium Silicate ◽  
Cementitious Material ◽  
Saturation Ratio ◽  
Tricalcium Aluminate ◽  
Cementitious Binder

A new kind of high strength cementitious material is made from phosphogypsum (PG), active carbon and fly-ash. Through the orthogonal research, it was showed that the calcination temperature, retention time, dosage of active carbon and fly ash on the compressive strength of cementitious binder are the most important. The result also showed that, in the conditions of temperature 1200°C, time retention 30 min, dosage of active carbon 10%, dosage of fly ash 5%, the compressive strength of the cementitious material for 3d and 28d could reach to 46.35MPa and 92.70MPa, the content of sulfur trioxide was 11.60% accordingly. A lot of active mineral materials, such as dicalcium silicate, tricalcium silicate, tricalcium aluminate were formed in the calcination. The C-S-H gel, calcium hydroxide and ettringite were found in 3d and 28d hydrates. It is found that the lime saturation ratio and silica modulus need to be control between 0.40~0.65 and 4~8 in order to produce high strength cementitious material.

scholarly journals Effect of Fly Ash on Compressive Strength, Drying Shrinkage, and Carbonation Depth of Mortar with Ferronickel-Slag Powder

2021 ◽  
Vol 11 (3) ◽  
pp. 1037
Author(s):  
Se-Jin Choi ◽  
Ji-Hwan Kim ◽  
Sung-Ho Bae ◽  
Tae-Gue Oh
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Construction Industry ◽  
Bituminous Coal ◽  
Raw Materials ◽  
Drying Shrinkage ◽  
The Other ◽  
Test Results ◽  
Slag Powder ◽  
Ferronickel Slag

In recent years, efforts to reduce greenhouse gas emissions have continued worldwide. In the construction industry, a large amount of CO2 is generated during the production of Portland cement, and various studies are being conducted to reduce the amount of cement and enable the use of cement substitutes. Ferronickel slag is a by-product generated by melting materials such as nickel ore and bituminous coal, which are used as raw materials to produce ferronickel at high temperatures. In this study, we investigated the fluidity, microhydration heat, compressive strength, drying shrinkage, and carbonation characteristics of a ternary cement mortar including ferronickel-slag powder and fly ash. According to the test results, the microhydration heat of the FA20FN00 sample was slightly higher than that of the FA00FN20 sample. The 28-day compressive strength of the FA20FN00 mix was approximately 39.6 MPa, which was higher than that of the other samples, whereas the compressive strength of the FA05FN15 mix including 15% of ferronickel-slag powder was approximately 11.6% lower than that of the FA20FN00 mix. The drying shrinkage of the FA20FN00 sample without ferronickel-slag powder was the highest after 56 days, whereas the FA00FN20 sample without fly ash showed the lowest shrinkage compared to the other mixes.

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