TY - JOUR
T1 - Measuring volume change caused by calcium oxychloride phase transformation in a Ca(OH)2-CaCl2-H2O system
AU - Qiao, C.
AU - Suraneni, P.
AU - Weiss, J.
N1 - Funding Information:
The writers gratefully acknowledge the financial support from the National Ready Mix Concrete Association (NRMCA), the Portland Cement Association (PCA), and a pooled fund by the Oklahoma Department of Transportation [TP-5 (297)] "Improving Specifications to Resist Frost Damage in Modern Concrete." The writers also acknowledge insightful discussions with Dr. Vahid Jafari Azad and Professor O. Burkan Isgor at Oregon State University. The content of this paper reflect the perspectives of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of a Department of Transportation or the Federal Highway Administration at the time of publication.
Funding Information:
The writers gratefully acknowledge the financial support from the National Ready Mix Concrete Association (NRMCA), the Portland Cement Association (PCA), and a pooled fund by the Oklahoma Department of Transportation [TP-5 (297)] “Improving Specifications to Resist Frost Damage in Modern Concrete.” The writers also acknowledge insightful discussions with Dr. Vahid Jafari Azad and Professor O. Burkan Isgor at Oregon State University. The content of this paper reflect the perspectives of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of a Department of Transportation or the Federal Highway Administration at the time of publication.
Publisher Copyright:
© 2017 by ASTM International.
PY - 2017
Y1 - 2017
N2 - Calcium oxychloride has been reported to form in cementitious materials when calcium chloride (CaCl2) solutions react with calcium hydroxide [Ca(OH)2]. In this study, Ca(OH)2 is mixed with CaCl2 solutions with concentrations of 5 %, 10 %, 15 %, 20 %, 25 %, and 30 % by weight, using a 1:1 M ratio of Ca(OH)2 to CaCl2. The Ca(OH)2-CaCl2 solution mixtures are subject to a cooling and heating cycle. Volume change is measured to quantify the phase transformation associated with calcium oxychloride. Low-temperature differential scanning calorimetry (LT-DSC) is used to construct a phase isopleth, which is used to quantify the phase transformation associated with calcium oxychloride. Hysteresis is observed in the volume-change measurement during the cooling-heating cycle. In a temperature range of 50°C to 0°C, the formation of calcium oxychloride is complete for the 20 %, 25 %, and 30 % CaCl2 solutions. The liquidus temperatures at which calcium oxychloride is expected to form from LT-DSC during heating match those from the volume-change measurements.
AB - Calcium oxychloride has been reported to form in cementitious materials when calcium chloride (CaCl2) solutions react with calcium hydroxide [Ca(OH)2]. In this study, Ca(OH)2 is mixed with CaCl2 solutions with concentrations of 5 %, 10 %, 15 %, 20 %, 25 %, and 30 % by weight, using a 1:1 M ratio of Ca(OH)2 to CaCl2. The Ca(OH)2-CaCl2 solution mixtures are subject to a cooling and heating cycle. Volume change is measured to quantify the phase transformation associated with calcium oxychloride. Low-temperature differential scanning calorimetry (LT-DSC) is used to construct a phase isopleth, which is used to quantify the phase transformation associated with calcium oxychloride. Hysteresis is observed in the volume-change measurement during the cooling-heating cycle. In a temperature range of 50°C to 0°C, the formation of calcium oxychloride is complete for the 20 %, 25 %, and 30 % CaCl2 solutions. The liquidus temperatures at which calcium oxychloride is expected to form from LT-DSC during heating match those from the volume-change measurements.
KW - Calcium chloride
KW - Calcium oxychloride
KW - Differential scanning calorimetry
KW - Phase diagram
KW - Volume change
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U2 - 10.1520/ACEM20160065
DO - 10.1520/ACEM20160065
M3 - Article
AN - SCOPUS:85025592598
VL - 6
SP - 157
EP - 169
JO - Advances in Civil Engineering Materials
JF - Advances in Civil Engineering Materials
SN - 2379-1357
IS - 1
ER -