کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10622785 989312 2005 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of alkali addition on the mechanical properties and durability of concrete
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی صنعتی و تولید
پیش نمایش صفحه اول مقاله
Effects of alkali addition on the mechanical properties and durability of concrete
چکیده انگلیسی
Increasing the concrete alkali content from 0.6% to 1.25% of Na2Oe of the cement mass by adding NaOH to the mixture water has harmful effects on most mechanical properties (compressive, splitting, direct tensile, and flexure strengths) of concrete made with a water-to-cement (w/c) ratio of 0.41 and limestone aggregates not susceptible to alkali-silica reaction (ASR), however not on the elasticity modulus measured under compression or direct tension. Shrinkage tests at 50% RH and 23 °C started after 7 days at 100% RH and 23 °C show that the low-alkali concrete shrinks more than the high-alkali one, despite similar water losses. Freeze-thaw tests performed on air-entrained concretes show that the two concretes resist well to freezing and thawing while showing similar air-void systems. When examined under the scanning electron microscope (SEM), the hydrates in the two concretes present similar microstructure; however, the high-alkali concrete shows a more reticular and porous microtexture, which could explain the reduction in strength.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cement and Concrete Research - Volume 35, Issue 2, February 2005, Pages 203-212
نویسندگان
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