· Figure 13 accordingly indicates the potential influence of incident heat fluxes, and thus the associated temperature and temperature gradients, on concrete properties at elevated temperatures. The challenging question is to quantify such influence and also to develop methodology to effectively account for it in fire design and analysis
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· The influence of temperature on the workability of normal strength concrete is well recognised—increasing temperature leads to workability deterioration [19,20]. The authors of the paper [ 21 ] also stated that there is an optimal temperature (about 20 °C) allowing them to obtain a concrete mixture with the most advantageous
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· Komendant J, Nicolayeff V, Polivka M, Pirtz D, "Effect of temperature, stress level, and age at loading on creep of sealed concrete", ACI special publication 55, 1978, 55-82.
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· Similarly, in the SRPC high- strength concrete, the chloride content was 1.91 and 2.1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 Depth (mm) Figure 1 Effect of exposure temperature on chloride ingress in conventional and
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· Another research studied the temperature effect from 20 to 80˚C showing a linear relationship between the increase in temperature and concrete carbonation depth (Drouet et al., 2019). The same
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· High-strength concrete is a material often used in the construction of high rise buildings. In the case of unexpected fire, the building concrete elements such as columns, slab and
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· After large-scale exploitation of conventional oil and gas resources, most remaining resources are in highly depleted zones, where the fracture pressure of the formations is greatly reduced. Low-density oil-well cement prevents wellbore and formation fractures by reducing annular liquid column pressure and is one of the most commonly
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· DSC test can measure cement hydration heat under non-isothermal conditions. Pressurized DSC test can measure cement hydration at ultrahigh temperatures. A model has been developed to simulate the temperature effect on cement hydration. The model has been verified by both DSC test and semi-adiabatic test.
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· The Ideal Temperature for Pouring Concrete. In order to avoid these issues, it's advised to pour concrete at a temperature between 50 to 60°F. Temperatures below 50°F will begin to slow the curing process, and the water in the cement is at risk of freezing at temperatures below 40°F. If the temperature is higher than 60°F, the water
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· The TGA result gives more obvious evidence for the impact of temperature on cement hydration during the initial reaction period with a comparison of the calorimetric result. The enhancement effect of rising temperature on hydrates formation is already remarkable in Stage I of the Gʹ evolution, which is reflected by the significantly
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· The LS replacement rate with the greatest effect on strength improvement was 20%, with fcu increased by 5–8%, fc increased by 6–8% and fr increased by 10–20%. At a temperature of 700
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· Consiste ncy of cement slurry is expressed in Bearden units of consistency ( Bc). The. Thickening Time (TT) test was performed using a High -Pressure- High-Temperatur e (HPHT) Consistometer rated
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· the postheated behavior of this cement subjected to elevated temperature has not been studied El-Hakim, E. Effect of high temperature or fire on heavy weight concrete properties . Cem. Concr
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· The mechanical strength results are displayed in Fig. 1.At room temperature (panels a and d), the mechanical strengths increase with hydration time as expected, the PC values being higher than those of BC up to 3 months.As previously reported, for instance in [30, 31], BC compressive strength surpassed that of PC above
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· The recommended concrete temperature range through batching, transport and placement falls between 50°-90°F based on established industry guidance: Maximum 90°F limit prevents accelerated slump loss and sets times. Minimum 50°F threshold prevents substantial delays or freezing. Ideally, aim for 60°-75°F for well
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· Curing temperature has a significant influence on cement paste microstructure and the properties of its principal hydrate C-S-H. In this paper, the effect of the hydration temperature in the range of 7 C to 90 C on the microstructure of a class G oil-well cement is studied.
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· Carbonate aggregate concrete exhibits higher specific heat in the temperature range of 600–800°, while siliceous aggregate concrete has higher thermal expansion. However, the thermal expansion of high strength concrete is not significantly impacted by the presence of steel fiber reinforcement at 800°.
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· For CEMV concrete, both mass increase and shrinkage progress until about 106 days maturation, where asymptotic values are reached (Fig. 3 (b)). Values from 106 to 184 days are similar, with an average mass increase of 0.92% ±0.02 of the initial sample mass, and an average shrinkage over the same period of −165 μm/m ±18.. The
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: Manisha Malik, S.K. Bhattacharyya, Sudhirkumar V. Barai · This research work presents the experimental investigations carried out to study the effect of elevated temperature on the durability characteristics of Normal Concrete (NC). Concrete specimens of different strength grades (M20, M30, M40, and M50) were cast, cured, and tested for compressive strength, water absorption, sorptivity
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· However, these phenomena occur at distinct temperatures, and affect the concrete structural elements differently. Fig. 5 and Fig. 6 summarize the influence of aggregate type on the compressive strength of Normal Strength Concrete(NSC). Furthermore, Fig. 7 It
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· The effect of temperature on thermal conductivity, thermal expansion, specific heat, and mass loss of HSC is discussed. Test data indicate that the type of aggregate has a significant influence on the thermal properties of HSC, while the presence of steel fiber reinforcement has very little influence on the thermal properties of HSC.
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· Effect of curing temperature on final setting times of blended cement pastes Fig. 5 illustrates the DSC thermograms of blended cement pastes containing slag, cured for 24 h at 40°C. Evidently, there were almost five
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· According to Sancak, et al. [31], the use of SF as substitution for cement causes concrete at elevated temperatures to lose more compression strength. In addition, Tang, et al. [32] found a positive impact of FA on concrete at high temperatures.
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This work reports the kinetics and structures of cement-limestone powder foams cast at the temperature between 27 and 42 °C. The pH, viscosity, flowability, temperature history and height of the slurries were measured, and the foaming kinetics was interpreted with the Weibull and Log-Logistic dose-time models.
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· Furthermore, the low temperature also affects the hydration of cement and change the microstructures of concrete at low temperature and cryogenic freeze–thaw cycles. How the mechanical properties of concrete exposed to low temperature and cryogenic freeze–thaw cycles during early age develops is still unknown.
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Such exposure to heightened temperatures can have a profound impact on concrete’s structural characteristics, resulting in diminished strength, rigidity, and resilience. Often,
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· Magnesium oxychloride cement (MOC), also known as magnesium cement, is a slurry prepared by combining a specific mass ratio of light burned magnesia powder and magnesium chloride solution. After solidification, it has superior mechanical properties [3,4], and it is a ternary system, MgO–MgCl 2 –H 2 O, at room temperature.
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· Although concrete is a noncombustible material, high temperatures such as those experienced during a fire have a negative effect on the mechanical properties. This paper studies the effect of elevated temperatures on the mechanical properties of limestone, quartzite and granite concrete. Samples from three different
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· Figure 13 accordingly indicates the potential influence of incident heat fluxes, and thus the associated temperature and temperature gradients, on concrete properties at elevated
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· temperature on the performance of fresh and hardened Portland cem ent concrete. In this work, concrete. mixtures were prepared usi ng different mixing water temperatures, 5, 15, 30, and
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