EFFECTS OF DEICING SALTS ON THE DURABILITY OF CONCRETE INCORPORATING SUPPLEMENTARY CEMENTITIOUS MATERIALS
type: CreativeWork
description: The durability of concrete mixtures incorporating one of two supplementary cementitious materials (SCMs), slag cement or Class C fly ash, exposed to sodium chloride (NaCl), calcium chloride (CaCl2), or magnesium chloride (MgCl2) is evaluated based on damage due to wetting and drying and scaling, with the goal of determining appropriate replacement levels of portland cement using these SCMs. The mixtures had water-to-cementitious material ratios of 0.38 and 0.44 and SCM percentage replacements of portland cement of 0%, 20%, 35%, and 50% by volume. Fourteen concrete mixtures (204 specimens) were cast to evaluate the damage to concrete subjected to 300 cycles of wetting and drying while exposed to solutions of one of the three deicing salts or deionized water in which the temperature of the specimens ranged from 39.2 ºF (4 ºC) during the wetting cycle to 73 ± 3 ºF (23 ± 2 ºC) during the drying cycle. Of special interest were the effects of CaCl2 and MgCl2, which result in the formation of calcium oxychloride. Durability was evaluated based on the average relative dynamic modulus of elasticity and the nature of physical damage, if any. Mixtures subjected to CaCl2 or MgCl2 that exhibit no spalling at test completion are considered to be durable. Ten concrete mixtures (156 specimens) were cast with curing periods of 14 or 28 days to investigate scaling over 56 cycles in accordance with Quebec test BNQ NQ 2621-900 using NaCl or CaCl2. Mixtures are considered durable if the average cumulative mass losses are less than the BNQ NQ 2621-900 failure limit of 0.10 lb/ft2. The results show that wetting and drying with deionized water or an NaCl solution does not cause deterioration of concrete. Exposure to CaCl2 and MgCl2, however, both of which result in the formation of calcium oxychloride, causes physical damage and a reduction in the dynamic modulus of concrete with portland cement as the only binder, with CaCl2 being the more deleterious of the two. A partial replacement of …
abstract: The durability of concrete mixtures incorporating one of two supplementary cementitious materials (SCMs), slag cement or Class C fly ash, exposed to sodium chloride (NaCl), calcium chloride (CaCl2), or magnesium chloride (MgCl2) is evaluated based on damage due to wetting and drying and scaling, with the goal of determining appropriate replacement levels of portland cement using these SCMs. The mixtures had water-to-cementitious material ratios of 0.38 and 0.44 and SCM percentage replacements of portland cement of 0%, 20%, 35%, and 50% by volume. Fourteen concrete mixtures (204 specimens) were cast to evaluate the damage to concrete subjected to 300 cycles of wetting and drying while exposed to solutions of one of the three deicing salts or deionized water in which the temperature of the specimens ranged from 39.2 ºF (4 ºC) during the wetting cycle to 73 ± 3 ºF (23 ± 2 ºC) during the drying cycle. Of special interest were the effects of CaCl2 and MgCl2, which result in the formation of calcium oxychloride. Durability was evaluated based on the average relative dynamic modulus of elasticity and the nature of physical damage, if any. Mixtures subjected to CaCl2 or MgCl2 that exhibit no spalling at test completion are considered to be durable. Ten concrete mixtures (156 specimens) were cast with curing periods of 14 or 28 days to investigate scaling over 56 cycles in accordance with Quebec test BNQ NQ 2621-900 using NaCl or CaCl2. Mixtures are considered durable if the average cumulative mass losses are less than the BNQ NQ 2621-900 failure limit of 0.10 lb/ft2. The results show that wetting and drying with deionized water or an NaCl solution does not cause deterioration of concrete. Exposure to CaCl2 and MgCl2, however, both of which result in the formation of calcium oxychloride, causes physical damage and a reduction in the dynamic modulus of concrete with portland cement as the only binder, with CaCl2 being the more deleterious of the two. A partial replacement of …
author: ABDUL BAKI, ALI NATHEER
language: en
keywords: Civil engineering, calcium oxychloride, concrete, durability, replacement percentage, scaling resistance, wetting and drying cycles
date published: 2020-08-31
date modified: 2026-07-24T02:45:07Z
provider: University of Kansas
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Kansas

PropertyValue
property ID: Handle
value: http://hdl.handle.net/1808/32588