Influence of Pore-Size Distribution on the Resistance of Clay Brick to Freeze-Thaw Cycles

Ivanka Netinger Grubeša; Martina Vračević; Jonjaua Ranogajec; Snežana Vučetić

doi:10.3390/ma13102364

Influence of Pore-Size Distribution on the Resistance of Clay Brick to Freeze-Thaw Cycles

Materials (Basel). 2020 May 21;13(10):2364. doi: 10.3390/ma13102364.

Authors

Ivanka Netinger Grubeša¹, Martina Vračević², Jonjaua Ranogajec³, Snežana Vučetić³

Affiliations

¹ Faculty of Civil Engineering and Architecture Osijek, Josip Juraj Strossmayer University of Osijek, Vladimira Preloga 3, 31000 Osijek, Croatia.
² Laboratory for Materials Testing, Civil Engineering Institute of Croatia, Drinska 18, 31000 Osijek, Croatia.
³ Faculty of Technology, University of Novi Sad, bul cara Lazara 1, 21000 Novi Sad, Serbia.

Abstract

This study examines the influence of raw material characteristics, methods of shaping and of parameters of firing process of clay bricks, on pore-size distribution and on resistance to freeze-thaw cycles (with particular emphasis on the retention time of the specimens at the maximum achieved temperature). Pore-size distribution was measured by mercury-intrusion porosimetry, while the resistance to freeze-thaw cycles was assessed by exposing the bricks to freeze-thaw cycles (HRN B.D8.011 standard) monitoring the appearance of surface changes, decrease of compressive strength as well as the Maage factor. A correlation was set up between the Maage factor and the ratio of the compressive strength before and after freezing as a quantitative indicator of bricks resistance to frost. By using this correlation for all the examined bricks, regardless of their raw material and shaping procedure, a low coefficient of correlation (R² = 0.26) was obtained. When processed separately, machine-made bricks had a significantly higher correlation coefficient value (R² = 0.60) than the hand-made bricks (R² = 0.28).

Keywords: Maage factor; clay bricks; compressive strength; firing regime; pore-size distribution; raw materials; resistance to freeze–thaw cycles; shaping procedure.