TORTUOSITY AND ELECTRICAL IMPEDANCE OF CONTAMINATED MORTARS WITH NITRATES OF Cr3+, Pb2+, AND Zn2+
Author(s): Venâncio, C., Rocha, J. C. and Cheriaf, M.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
Publication year: 2015
Total Pages: 8
Abstract: This research evaluated the physical properties that influence in the durability of the cementitious materials, such as tortuosity and sorptivity. The tortuosity is an important parameter that defines the permeability and the configuration of the flow channels through which can flow a fluid.
Due to the technical difficulties of the determination of the tortuosity, the electrical measurements are proposed and they were performed in mortars after 28 days of age. The mortars were contaminated with heavy metals, nitrates of Cr3+, Pb2+, and Zn2+ in order to simulate cementitious materials produced with contaminated wastes. After that, a test of capillary absorption was carried out in these contaminated mortars. Thus, also was evaluated the influence of heavy metals in the physical properties of cementitious materials.
The results showed that the contaminants influence differently in the capacity of water capillary absorption (sorptivity) and in the configuration of the pores (tortuosity). Chromium decreased and zinc increased the sorptivity of the mortars. These data of sorptivity reflected in the values of tortuosity that were less with the addition of the heavy metals in the mortars. Therefore, the heavy metals may alter the durability of cementitious materials.
Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00