CALTRANS: Impact of the Use of Portland-Limestone Cement on Concrete Performance as Plain or Reinforced Material

Estimating Na+ and K+ concentrations of the pore solution based on ex-situ leaching tests and thermodynamic modeling

“…1, the kinetics of the OPC clinker reactions were simulated using the Parrott and Killoh (PK) model for the OPC mixtures [29], and the modified Parrott and Killoh (MPK) model for OPC + FA mixtures [30]. The reactivity of the fly ash used in this study, which is an indicator for the reactive portion of the material, was determined by the Pozzolanic Reactivity Test [31][32][33][34]. Alternatively, the cementitious materials could be analyzed using quantitative X-ray diffraction (QXRD) -from which the crystalline phases and amorphous content of the SCM can be determined.…”

“…. However, the distinction of capillary and gel water is necessary for implementing v PSE in the concentration adjustment, which will be described in the following section [30][31][32][33][34]37,38].…”

“…After 10 days, the sample was removed from the calorimeter and a 20 mg sample was used to determine the remaining CH content from TGA [31,47]. The DOR* for the fly ash used in this study was 37.15% as reported in detail elsewhere [32,33]. The DOR* value was then used in the modified Parrot-Killoh (MPK) [30] to determine the oxide content of the fly ash to include in thermodynamic modelling of the samples in this study.…”

Predicting Fracture from Thermodynamic Modeling of Cementitious Systems

“…13 This often does not take full advantage of the benefits of the SCM being added to the system, such as improvements to the compressive strength of concrete made with the SCM. [14][15][16][17] Sometimes, empirical modifications are made to predict the compressive strength of systems containing SCMs like fly ash 18 ; however, these calibrations are typically SCM-specific. Many historical SCM sources are changing or becoming less available, 3,5,19 and as a result, there has been a desire to identify alternative SCMs (for example, municipal waste incineration ash, bottom ash, boiler slag, natural pozzolans, and agricultural waste ash), [20][21][22][23][24][25][26][27][28][29] and to develop approaches to use off-spec materials.…”

“…The tool can then be used for any cementitious material combination, in any proportion, to predict key properties of the hydrated system, including strength, porosity, electrical resistivity, formation factor, and ionic diffusion coefficients. 8,16,17,40,41 These predicted properties have been used to develop performancebased mixture proportioning methods 8,20 and service life prediction models. 45 Despite these recent developments, there are opportunities to improve the models.…”