Title: Use of Electrical Resistance Probes in Tracing Moisture Permeation Through Concrete

Author(s): Gunars Bracs, Emery Balint, and Dennis F. Orchard

Publication: Journal Proceedings

Volume: 67

Issue: 8

Appears on pages(s): 642-647

Keywords: compressive strength; concretes; electrical resistance; hardened concretes; moisture;permeability; porosity; research; voids.

DOI: 10.14359/7302

Date: 8/1/1970

Abstract:
Describes the development and application of a method, based on measuring electrical resistance, for the tracing of moisture transfer through specimens of concrete. Cured and dried specimens of various concretes were subjected to a small, constant head of water and frequent measurements of electrical resistance were taken between embedded pairs of electrodes. Since the conductivity of moisture reduced the local resistance, advance of the moisture in the specimen could be traced. Results were interpreted with the aid of records of moisture volumes involved in the process of permeation. It was found that the oven-dried specimens were fully permeated within a few days but then, over the total period of I20 days, hard-ening and reduction of permeability occurred. Specimens were classed and concrete quality determined according to these two factors: initial speed of permeation and later reduction of permeability.