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| Avtorstvo: |
Jana ŠELIH // 1.01 Izvirni znanstveni članek
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| Leto: |
1996 |
| Citat: |
ŠELIH, Jana. Gibanje vlage med sušenjem nasičenega betona. Gradb.
vestn., januar-februar 1996, let. 45, št. 1-2, str. [41-50]. |
| Povzetek: |
V
članku je predstavljena raziskava spreminjanja vsebnosti vode v betonu med
sušenjem. Poudarek je na začetni fazi tega procesa, kjer je vsebnost vode
visoka in za katero je v literaturi le malo padatkov. Eksperimentalne in
numerične raziskave so potekale na betonskih cilindrih, izpostavljenih
sušenju na zgornji površini. Cilindri so narejeni iz normalnega in lahkega
betona s spreminjajočim se vodocementnim faktorjem. Vpliv teh spremenljivk
na proces izsuševanja smo eksperimentalno ovrednotili. V primerjavi z
normalnim so v lahkem betonu višji nivoji vsebnosti vode, povečanje
vodocementnega faktorja pa poveča hitrost sušenja. Visoke, konstantne
vrednosti hitrosti sušenja opazimo v začetni fazi sušenja tako med
eksperimentom kot z numerično simulacijo. Razviti numerični model temelji na
posplošeni matematični formulaciji masnega in toplotnega prenosa v poroznih
materialih, njegovi rezultati pa se ujemajo z eksperimentalnimi podatki
znotraj pričakovane negotovosti vhodnih podatkov.
Moisture
transport in fully saturated concrete during drying. Moisture content
changes during drying were investigated in the present work. Particular
emphasis was placed on the initial stage of drying of saturated concrete,
where moisture contents are high. For this stage of drying, experimental
data are lacking, and no comprehensive theory exist to describe it. The
present investigation was performed experimentally and numerically for
drying of cylinders with one exposed end, made of normal weight and
lightweight concrete with varying water to cement ratio. The lightweight
concrete cylinders as compared to those made of normal weight concrete
exhibited higher levels of moisture content throughout the process. At high
w/c ratios, the moisture profiles for both types of cylinders, as expected,
show steeper changes with time. Large, constant drying were observed both
experimentally and numerically in the beginning of the drying. The numerical
model developed is based on a generalized mathematical formulation for mass
and heat transfer in porous media, and its predictions are in good agreement
with the experimental data with the uncertainty range of the input data.
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| Tipologija: |
1.01 Izvirni znanstveni članek |
| COBISS ID |
16787461 Polni zapis iz sistema COBISS |
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Vpisal 2001/08/08 19:56
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