NEUTRON RADIOGRAPHY MEASUREMENT OF SALT SOLUTION ABSORPTION IN MORTAR.

Autor: Lucero CL, Spragg RP, Bentz DP, Hussey DS, Jacobson DL, Weiss WJ
Jazyk: angličtina
Zdroj: ACI materials journal [ACI Mater J] 2017 Jan 01; Vol. 114 (1), pp. 149-159.
DOI: 10.14359/51689488
Abstrakt: Some concrete pavements in the US have recently exhibited premature joint deterioration. It is hypothesized that one component of this damage can be attributed to a reaction that occurs when salt-laden water is absorbed in the concrete and reacts with the matrix. This study examines the absorption of CaCl 2 solution in mortar via neutron imaging. Mortar specimens were prepared with water to cement ratios, ( w/c ), of 0.36, 0.42 and 0.50 by mass and exposed to chloride solutions with concentrations ranging from 0 % to 29.8 % by mass. Depth of fluid penetration and moisture content along the specimen length were determined for 96 h after exposure. At high salt concentration (29.8 %), the sorption rate decreased by over 80 % in all samples. Along with changes in surface tension and viscosity, CaCl 2 reacts with the cement paste to produce products (Friedel's salt, Kuzel's salt, or calcium oxychloride) that block pores and reduce absorption.
Databáze: MEDLINE