کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1456800 989224 2012 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Permeability and elastic modulus of cement paste as a function of curing temperature
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی صنعتی و تولید
پیش نمایش صفحه اول مقاله
Permeability and elastic modulus of cement paste as a function of curing temperature
چکیده انگلیسی

The permeability and elastic modulus of mature cement paste cured at temperatures between 8 °C and 60 °C were measured using a previously described beam bending method. The permeability increases by two orders of magnitude over this range, with most of the increase occurring when the curing temperature increases from 40 °C to 60 °C. The elastic modulus varies much less, decreasing by about 20% as the curing temperature increases from 20 °C to 60 °C. All specimens had very low permeability, k < 0.1 nm2, despite having relatively high porosity, ϕ ~ 40%. Concomitant investigations of the microstructure using small angle neutron scattering and thermoporometry indicate that the porosity is characterized by nanometric pores, and that the characteristic size of pores controlling transport increases with curing temperature. The variation of the microstructure with curing temperature is attributed to changes in the pore structure of the calcium–silicate–hydrate reaction product. Both the empirical Carmen–Kozeny, and modified Carmen–Kozeny permeability models suggest that the tortuosity is very high regardless of curing temperature, ξ ~ 1000.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cement and Concrete Research - Volume 42, Issue 2, February 2012, Pages 440–446
نویسندگان
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