Influence of the relative humidity on the hydration kinetics of concrete

The paper focuses on the evaluation of the rheological and mechanical performances of cement-based renders manufactured with phase-change materials (PCM) in form of microencapsulated paraffin for innovative and ecofriendly residential buildings. Specifically, cement-based renders were manufactured by incorporating different amount of paraffin microcapsules—ranging from 5% to 20% by weight with respect to binder. Specific mass, entrained or entrapped air, and setting time were evaluated on fresh mortars. Compressive strength was measured over time to evaluate the effect of the PCM addition on the hydration kinetics of cement. Drying shrinkage was also evaluated. Experimental results confirmed that the compressive strength decreases as the amount of PCM increases. Furthermore, the higher the PCM content, the higher the drying shrinkage. The results confirm the possibility of manufacturing cement-based renders containing up to 20% by weight of PCM microcapsules with respect to binder.

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Hydration kinetics of CA2 and CA—Investigations performed on a synthetic calcium aluminate cement

Cement and Concrete Research ◽

10.1016/j.cemconres.2012.09.005 ◽

2013 ◽

Vol 43 ◽

pp. 62-69 ◽

Cited By ~ 63

Author(s):

S.R. Klaus ◽

J. Neubauer ◽

F. Goetz-Neunhoeffer

Keyword(s):

Calcium Aluminate ◽

Calcium Aluminate Cement ◽

Hydration Kinetics ◽

Kinetics Of ◽

Aluminate Cement

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Degradation of hydration kinetics of proton-conducting Ba(Zr0.84Y0.15Cu0.01)O3−δ during conductivity-relaxation experiment

Journal of Power Sources ◽

10.1016/j.jpowsour.2016.09.129 ◽

2016 ◽

Vol 332 ◽

pp. 299-304 ◽

Cited By ~ 2

Author(s):

Sung Min Choi ◽

Jong-Heun Lee ◽

Jongsup Hong ◽

Kyung Joong Yoon ◽

Ji-Won Son ◽

...

Keyword(s):

Conductivity Relaxation ◽

Hydration Kinetics ◽

Proton Conducting ◽

Relaxation Experiment ◽

Kinetics Of

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Oxygen Absorption Kinetics of Sheets and Films Containing a Commercial Iron-based Oxygen Scavenger

Food Science and Technology International ◽

10.1177/1082013208106207 ◽

2009 ◽

Vol 15 (2) ◽

pp. 159-168 ◽

Cited By ~ 19

Author(s):

M.J. Galotto ◽

S.A. Anfossi ◽

A. Guarda

Keyword(s):

Relative Humidity ◽

Kinetic Parameters ◽

Oxygen Absorption ◽

Absorption Kinetics ◽

Oxygen Scavenger ◽

Arrhenius Behavior ◽

Oxygen Scavengers ◽

Iron Based ◽

Empirical Growth ◽

Kinetics Of

Absorption kinetics of three different forms of the same iron-based oxygen scavenger were studied. Oxygen scavengers were used as pellet, sheet, and film materials. Two scavenger concentrations were used for sheet and film forms. Scavenger samples were analyzed at 75 or 100% relative humidities and stored at 5, 15, and 25°C. Oxygen concentration in the headspace was measured as a function of time. Absorption kinetics was best described by the Chapman-Richards empirical growth model rather than by a first-order reaction. Arrhenius behavior was observed for variations in the final absorption rate with temperature. Absorption capacities, final absorption rates, and activation energies were evaluated and discussed. Scavenger concentration, relative humidity, and temperature effects on kinetic parameters were studied for each experimental condition. Temperature was the most important factor that affected kinetic parameters. At the relative humidity levels studied, any important effect on kinetic parameters was not observed, except on absorption capacities.

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