Portland Cement Based Lightweight Multifunctional Matrix with Different Kind of Additives Containing SiO2

2014 ◽  
Vol 604 ◽  
pp. 305-308 ◽  
Author(s):  
Ina Pundienė ◽  
Modestas Kligys ◽  
Jurga Šeputytė-Jucikė
Keyword(s):  
Compressive Strength ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Dynamic Viscosity ◽  
Building Materials ◽  
Hydration Process ◽  
Aerated Concrete ◽  
Wetting Heat ◽  
Pozzolanic Properties

Additives containing SiO2 (ACS) and having pozzolanic properties such as metakaolin (MK), microsilica (MS) and milled autoclaved aerated concrete waste (MAACW) are promising materials for partially replacement of Portlandcement (PC) in matrix of lightweight building materials. Studies have shown that SA effects on the hydration process of PC matrix. The highest wetting heat release rate values were obtained using MS additive, and the lowest a mix of MS and MK additives. In a mix with both MS and MK additives, the maximal value of heat release rate was reached after 10 h and in a mix with MS additive after 13 h. MS additive extends while MK additive accelerates the hydration process of PC. The most effective plasticizer (P) was chosen according to the study of dynamic viscosity (DV) of PC matrix. It was fixed that surfactant (SU) in amount of 0.03 % (from PC) reduces the density of matrix about 30 % compared with the density of matrix without SU. Increased quantity of MAACW (from 5 to 15 % from PC) causes in increase of compressive strength of PC matrix (after 28 days curing) from 19 to 47 MPa.

Exothermal Behavior during the Hydration of the PCCP+DCPA System Cement

2009 ◽  
Vol 610-613 ◽  
pp. 1255-1258 ◽  
Author(s):  
Xiu Peng Wang ◽  
Jian Dong Ye
Keyword(s):  
Particle Size ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Dicalcium Phosphate ◽  
Hydration Process ◽  
Dicalcium Phosphate Dihydrate ◽  
Tetracalcium Phosphate ◽  
Phosphate Dihydrate ◽  
Close Relationship

Exothermal behavior is always present during the hydration of cements. The biocompatibility and curing effect of a bone cement is in close relationship with its exothermal behavior. The exothermal behavior in the hydration process of the partially crystallized calcium phosphate (PCCP)+dicalcium phosphate anhydrate (DCPA) system cement was studied in this article. The results show that with the decrease of the particle size of DCPA, the heat release rate was greatly increased; whereas, with the decrease of the particle size of PCCP, the heat release rate was not obviously altered. The heat release in the hydration process of the PCCP+DCPA system cement was only 137 J/g, which was quite smaller than that of the tetracalcium phosphate (TTCP)+dicalcium phosphate dihydrate (DPCD) system cement, and the temperature increase was very small for this cement.

scholarly journals Influence and Mechanism Research of Hydration Heat Inhibitor on Low-Heat Portland Cement

2021 ◽  
Vol 8 ◽  
Author(s):  
Fujie Jia ◽  
Yan Yao ◽  
Jingyu Wang
Keyword(s):  
Compressive Strength ◽  
Sustained Release ◽  
Portland Cement ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Setting Time ◽  
Hydration Heat ◽  
Adiabatic Temperature Rise ◽  
Mechanism Research

A kind of microcapsule sustained-release–type hydration heat inhibitor (MSR) was prepared. The effect of MSR on semi-adiabatic temperature rise, setting time, and strength of low-heat Portland cement was investigated. Microcalorimetry, XRD, SEM, and TG-DSC were used to investigate the mechanism of MSR on hydration of low-heat Portland cement. The results showed that the MSR had good regulating effect on hydration of low-heat Portland cement. When the dosage of MSR was 0.3%, the heat release rate decreased by 10% and the peak temperature decreased by 52%. The 3D compressive strength decreased by 50%, and the 28-day strength was the same as control. The MSR can delay the hydration of low-heat Portland cement by inhibiting the heat release rate of C2S and C3S minerals.

Scale Modeling on the Effect of Air Velocity on Heat Release Rate in Tunnel Fire

2008 ◽  
Vol 18 (2) ◽  
pp. 111-124 ◽  
Author(s):  
C. Chen ◽  
L. Qu ◽  
Y. X. Yang ◽  
G. Q. Kang ◽  
W. K. Chow
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Air Velocity ◽  
Tunnel Fire ◽  
Scale Modeling

scholarly journals Effects of Discharge Area and Atomizing Gas Type in Full Cone Twin-Fluid Atomizer on Extinguishing Performance of Heptane Pool Fire under Two Heat Release Rate Conditions in an Enclosed Chamber

2021 ◽  
Vol 11 (7) ◽  
pp. 3247
Author(s):  
Dong Hwan Kim ◽  
Chi Young Lee ◽  
Chang Bo Oh
Keyword(s):  
Heat Release ◽  
Flow Rate ◽  
Heat Release Rate ◽  
Release Rate ◽  
Water Mist ◽  
Pool Fire ◽  
Sauter Mean Diameter ◽  
Discharge Area ◽  
Fire Extinguishing ◽  
Enclosed Chamber

In this study, the effects of discharge area and atomizing gas type in a twin-fluid atomizer on heptane pool fire-extinguishing performance were investigated under the heat release rate conditions of 1.17 and 5.23 kW in an enclosed chamber. Large and small full cone twin-fluid atomizers were prepared. Nitrogen and air were used as atomizing gases. With respect to the droplet size of water mist, as the water and air flow rates decreased and increased, respectively, the Sauter mean diameter (SMD) of the water mist decreased. The SMD of large and small atomizers were in the range of approximately 12–60 and 12–49 μm, respectively. With respect to the discharge area effect, the small atomizer exhibited a shorter extinguishing time, lower peak surface temperature, and higher minimum oxygen concentration than the large atomizer. Furthermore, it was observed that the effect of the discharge area on fire-extinguishing performance is dominant under certain flow rate conditions. With respect to the atomizing gas type effect, nitrogen and air appeared to exhibit nearly similar extinguishing times, peak surface temperatures, and minimum oxygen concentrations under most flow rate conditions. Based on the present and previous studies, it was revealed that the effect of atomizing gas type on fire-extinguishing performance is dependent on the relative positions of the discharged flow and fire source.

scholarly journals Heat release rate shaping for optimal gross indicated efficiency in a heavy-duty RCCI engine fueled with E85 and diesel

Fuel ◽  
2021 ◽  
Vol 288 ◽  
pp. 119656
Author(s):  
Robbert Willems ◽  
Frank Willems ◽  
Niels Deen ◽  
Bart Somers
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Heavy Duty ◽  
Rate Shaping
Sign in / Sign up

Export Citation Format

Share Document