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The relatively high R 2 values (between 0.7709 and 0.9777) demonstrate a direct relationship between porosity and permeability for the three types of porous concrete studied, as evidenced by the graphs. Data dispersion is minimal in Types I and II, supporting a very strong relationship between the variables.
This study investigated the performance of two high-volume fly ash concrete (HVFAC) mixes with 70% replacement of Portland cement with a Class C fly ash (with one mix having a relatively high ...
For the ed concrete containing high volume FA, a series of problems such as low early strength and easy cracking due to low reactivity of FA have been reported [ 11, 27, …
The effects of limestone powder (LP) of different fineness on the packing density, strength and hydration behaviour of cement blended with a high volume of LP were studied using Vicat setting time ...
(a) Compressive strength of the different additions at days 1 and 28 as a function of the water-to-cement ratio; (b) Evolution of the slump flows measured with the shock table after 10, 13 and 16 ...
Compressive strength models have been proposed based on the conceptual postulation of how the hydrated cement interacts with other particles (i.e., aggregates) and harden [30].The literature demonstrates that Feret was the first to develop a relationship between compressive strength and the ratio of cement to paste and air, as shown by expression 1 in …
The long-term chloride permeability of the concrete containing limestone powder is higher than that of plain cement concrete under the condition of equal 28-day compressive …
In this contribution, the 28-day compressive strength of cement-based materials including grout, normal concrete, lightweight concrete, and ed concrete was investigated. Abrams' law and Bolomey's formula were applied for simulation of the relationship between water-cement ratio and 28-day compressive strength.
Extensive work has been conducted on material properties of CNTs reinforced cement composites (CNTRCCs). Mousavi et al. [16] added CNTs and titanium dioxide nanoparticles simultaneously to cement slurry and studied the effect of fillers on mechanical properties. They used response surface methodology to simulate the 28-day compressive and …
In concretes without added nano CaCO 3, PLC concrete has higher strength than OPC concrete up to 7 days, while at 28 days, both the concretes have comparable strengths. Limestone …
The impact resistance of the hardened cement pastes is determined by the Charpy impact test at the ages of 7, 14, and 28 days. Besides, the compressive strength at 28 days of the paste is also ...
In this study, the hydration of Portland-limestone cement (PLC) pastes and the relationship between compressive strength and porosity of PLC mortar samples containing …
Download scientific diagram | 28-days versus 90-days compressive strength (MPa) relationship. from publication: Chloride Diffusion in Concrete Made with Coal Fly Ash Ternary and Ground Granulated ...
In particular, the 28-day compressive strength (hereinafter referred to as f 28) is a fundamental criterion of concrete performance. The development of f 28 is multifaceted and depends on various factors, including mix proportions, physical and chemical properties of mixing constituents, and environmental conditions such as outdoor weather (i.e ...
The replacement percentage of metakaolin employed was 5%, 10%, 15% and 20% by weight of cement with a mix ratio of cement to sand to granite of 1:2:4 cured at 7 days, 14 days, 28 days and 56 days .
Therefore, exploring the relationship between the DOH of cement and compressive strength in different studies as a whole is not very meaningful. Fig. 9 illustrates the relationship between the DOH of cement and compressive strength when the cement content is constant, both for changes in age [22, 107], or the change of curing regime [73]. It ...
A comparable 56-day compressive strength was observed for PLC with 1% nano CaCO 3. The strength, however, exceeded the strength for OPC by 7% when a modified mixing sequence was used. Permeability at 56-days and ASR …
The water-to-cement ratio varies within a range of 0.29–1.91. All curves exhibit an upward trend, indicating a positive correlation between cement content and the compressive strength of concrete. The increasing compressive strength with the increase of cement for a given quantity of water indicates the hydration process efficacy.
The hydration, compressive strength, and porosity of a high-C 3 A cement clinker interground to make five types of cements with different limestone contents and their combinations with various levels of SCMs were examined. The cements used had limestone contents of 0%, 2.4%, 10.6%, 12.7%, and 21.8%, labeled Type I, GU, PLC11, PLC13 and PLC22, respectively.
It is found that although the pozzolanic reaction of FA is much lower than that of Portland cement, using limestone powder in high volume fly ash OPS concrete can significantly improve its compressive strength at early ages (first 3 days). ... compared to the AC condition, the compressive strength improved by about 2%, 17%, 14% and 19% for ...
However, PQGC formulated with SS, w.r.t PQGC containing RS, exhibited enhanced mechanical strength of 7% in compression, 16.7% in flexure and 8.3% in split tensile tests at 28 days of open ...
Among the quantities describing concrete mix design, w/c ratio is the preferred parameter since it characterizes all performance-related properties and durability of hardened ordinary and high performance concretes (HPC) [1], [2], [3].The relation between w/c and properties of concrete is related to the cement paste capillary porosity being proportional to the …
Systematic evaluations of hydration kinetics, compressive strength development, and carbonation resistance are crucial for the rational use of limestone. This study presents a …
The evolution of phase volume fractions of hydration products were calculated. In summary, current hydration models mainly focus on cement-limestone hydration [8,9,10,11,16] and strength development [12,13,14,15]. The relations between cement-limestone hydration and durability aspects, such as carbonation, are scarcely considered.
Results showed that autogenous shrinkage of GGBFS blends continuously increased after 28 days (until 100 days) whereas the control samples reached a plateau after about 28 days. Late reaction between limestone from the General Purpose cement and alumina from GGBFS progressed untill 90 days forming a high amount of monocarboaluminates.
For an average Portland cement concrete cured under normal temperature and moisture, Abrams gave the relationship between compressive strength and water/cement ratio as [5]; (4) f c 7 = 63.45 14 x and f c 28 = 96.55 8.2 x where, f c 7 and f c 28 are the strengths in MPa at 7 and 28 days, respectively.
The water-cement-density ratio law will be beneficial for the precise and generalized prediction of the 28-day standard curing compressive strength of cement-based materials.
The addition of limestone powder enhanced the early compressive strength of UVLP-ECC specimens. Specifically, the compressive strength of UVLP-ECC mortar reached …
However, PQGC formulated with SS, w.r.t PQGC containing RS, exhibited enhanced mechanical strength of 7% in compression, 16.7% in flexure and 8.3% in split tensile tests at 28 days of open ...
However, increasing the curing period from 7 to 28 days resulted in an unexpected average reduction in concrete compressive strength of 13%. Despite previous results, a …
To quantify this impact, the empirical relationship between the carbonation resistance and the compressive strength of the high-volume limestone powder concrete (HVLPC) was established.
Concrete structures are designed on the basis of 28 days cylinder crushing strength. 28 days cylinder strength actually represents the characteristic strength of the concrete. It is mandatory to test the concrete cylinders at the age of 28 …
The 3-days or 7-days tests are done to assess the early gain of concrete strength and make a crude estimate of the 28 day strength at site. However, 28-days tests are mandatory as per design ...
It can be shown that there has a highly significant positive linear correlation was observed between strength and heat. The relationship between R cm-28 d and Q 72h of blended cement pastes can be classified into two zones: (I) heat and strength values fluctuate at ± 15% compared to the control test mixed with Portland cement and (П ...
Time and strength gain: time and strength of cement relationship are non linear. 1) 1 day of curing time cement gain its strength about 16% of total strength 2) 3 days of curing time cement gain its strength about 40% of total strength 3) 7 days of curing time cement gain its strength about 65% of total strength 4) 14 days of curing time cement ...
The effectiveness of bassanite in improving the early strength of high-volume HT–cement systems was investigated in this study. ... After 28 days, the strength of the ACC specimens was approximately 1.3 times that of the sealed curing group. ... there was a linear relationship between the strength and combined water; 3) for the ternary ...