Description
Summary: | Scandinavian researchers have identified reduction of moisture content to 6 percent and sufficient prehardening as conditions under which mortar in masonry walls will withstand early freezing without damage. This paper reports the results of a study in which volume changes due to freezing were measured in mortars to assess these conclusions for Canadian masonry materials. Volume changes in mortar samples encased in a rubber balloon immersed in alcohol in a cylinder connected to a calibrated capillary were measured as the temperature was lowered through the freezing zone. The effect of variable moisture contents and setting times for a 1:1:6 cement-lime mortar and a 1:3 masonry-cement mortar were studied. It was found that freezing expansions of the order of 2 percent for cement-lime mortar control samples dropped sharply after a setting time of 4 h and virtually disappeared at 16 h. Expansions of 1.25 percent in masonry-cement control mortars decreased to negligible values after a setting time of 4 h. Reductions to 6 percent moisture content reduced freezing expansions to negligible values for both mortars, although problems were encountered in bringing moisture contents down to 6 percent. The possible application of the results to field conditions is discussed
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Physical Description: | 1 online resource (11 pages) : illustrations, figures, tables |
Bibliography: | Includes bibliographical references and indexes |
Access: | Restricted for use by site license. |