Conference, Proceedings

More documents

Recommendations

Info

Thermal properties The thermal parameters data in Table 6 show that both materials achieved similar values of thermal conductivity in the whole range of moisture content. This was not in a good agreement with the open porosity data in Table 3 as in general a material with higher porosity should have lower thermal conductivity. However, the differences between both materials were relatively low, within the error range of the measuring method. Also, the lowering of matrix density after 1‐year as compared to the 28‐days results indicated a possible change in the composition of the porous matrix, the lowering of the open porosity then a change in the topology of the pore space which could be manifested in somewhat different way of mixing the basic phases into the resulting thermal conductivity values. The differences in specific heat capacity of both materials were in the whole moisture range relatively low, up to 10%, which was well within the error range of the measurement method. Conclusions 198 Type of mixture Table 6: Thermal properties of SCC after 28 days u λ c [% kg‐water/kg‐ dry material] [Wm ‐1 K ‐1 ] [Jkg ‐1 K ‐1 ] SCC‐3 0.0 2.84 716 SCC‐3 2.1 3.27 728 SCC‐3 3.8 3.42 725 SCC‐3 4.4 4.17 733 SCC‐4 0.0 2.79 639 SCC‐4 1.8 3.45 764 SCC‐4 3.4 3.70 766 SCC‐4 3.7 3.78 738 The results of measurement of basic physical parameters and the hygric and thermal properties of SCC produced with cement containing blast furnace slag in this paper showed that the effect of slag was positive in a long term view. Comparing the results obtained 28 days and 1 year after mixing, the values of open porosity, water vapor diffusion coefficient and water absorption coefficient were after 1‐year significantly lower than the corresponding 28‐days data. This indicates an improvement of durability. The thermal conductivity and specific heat capacity of the studied SCC were for both time periods almost the same, within the error range of the experimental methods. The obtained data can be considered as a step towards establishment of a material database for SCC which is currently not available and which should serve for hydro‐thermo‐chemo‐ mechanical models, making it possible to perform complex durability and reliability based studies of building constructions involving SCC in various applications.
Acknowledgements This research has been supported by the Czech Ministry of Education, Youth and Sports, under project No MSM 6840770031. References [1] OZAWA K., KUNISHIMA M., MAEKAWA K., Development of high performance concrete based on the durability design of concrete structures. <strong>Proceedings</strong> of the second East‐Asia and Pacific <strong>Conference</strong> on Structural Engineering and Construction (EASEC‐2), Vol. 1, pp. 445‐450, January 1989. [2] OZAWA K., MAEKAWA K., OKAMURA H., Development of high performance concrete. J. Faculty Eng. Univ. Tokyo (B), 1992, XLI(3), 381‐439. [3] OKAMURA H., MAEKAWA K., OZAWA K., High Performance Concrete, Gihoudou Pub., Tokyo 1993. [4] OKAMURA H., OZAWA K., Mix design for self‐compacting concrete. Concrete Library, JSCE, No. 25, pp. 107‐120, June 1995. [5] ZHU W., BARTOS P.J.M., Permeation properties of self‐compacting concrete. Cement and Concrete Research 33(2003), 921‐926. [6] PERSSON B., A comparison between mechanical properties of self‐compacting concrete and the corresponding properties of normal concrete. Cement and Concrete Research 31(2001), 193‐198. [7] SARI M., PRAT E., LABASTIRE J.F., High strength self‐compacting concrete. Original solutions associating organic and inorganic admixtures. Cement and Concrete Research 29(1999), 813‐818. [8] ROELS, S., CARMELIET, J., HENS, H., ADAN, O., BROCKEN, H., ČERNÝ, R., PAVLÍK, Z., HALL, C., KUMARAN, K., PEL, L,, PLAGGE, R., Interlaboratory Comparison of Hygric Properties of Porous Building Materials. Journal of Thermal Envelope and Building Science 27 (2004) 307‐325. [9] KUMARAN, M.K., Moisture Diffusivity of Building Materials from Water Absorption Measurements.IEA Annex 24 Report T3‐CA‐94/01, Ottawa 1994. [10] ČERNÝ R, ROVNANÍKOVÁ P., Transport Processes in Concrete. Spon Press, London 2002. 199
Page 1 and 2:
Thermophysics 2009 29 th and 30 th
Page 3 and 4:
Content Ivan Baník, Jozefa Lukovi
Page 5 and 6:
Measurement of the thermo‐physica
Page 7 and 8:
As the right side of the previous r
Page 9 and 10:
The initial vector k r in the k1, k
Page 11 and 12:
2.4 The computer programs testing T
Page 13 and 14:
Investigation of moisture influence
Page 15 and 16:
⎛ t t ⎞ −1 ⋅ ln⎜ ⎝ tm t
Page 17 and 18:
Density [kg.m -3 ] 620 600 580 560
Page 19 and 20:
for a new building have to be great
Page 21 and 22:
Fig.1. Photo of the hot ball sensor
Page 23 and 24:
Fig.6.Left: formation of blocks. Ri
Page 25 and 26:
4. Conclusions With this experiment
Page 27 and 28:
1a. Three‐dimensional temperature
Page 29 and 30:
n+ ∞ ( ) 4 ( ) ∑ π n= 1 ( 2 1)
Page 31 and 32:
a 2 2 ( Fo) ⎛ l ⎞ r = ⎜ ⎟
Page 33 and 34:
Substitution of ordinates of the in
Page 35 and 36:
Moisture transport through porous m
Page 37 and 38:
Data acquired through the hot ball
Page 39 and 40:
In this way, the water spreading wa
Page 41 and 42:
Thermal conductivity [W m -1 K -1 ]
Page 43 and 44:
Relationship between relative permi
Page 45 and 46:
( ) i n Φ − Φ K i = ki i i, cri
Page 47 and 48:
Figure 4: Comparison of measured an
Page 49 and 50:
Computational modelling of coupled
Page 51 and 52:
a ξ = d 2 ( lnκ − lnκ ) lnξ +
Page 53 and 54:
on the results of experiments and c
Page 55 and 56:
Figures 8a, b: Moisture content (a)
Page 57 and 58:
Conclusions The computer simulation
Page 59 and 60:
properties as are the bulk density,
Page 61 and 62:
elation determined from the measure
Page 63 and 64:
In the evaluation of the difference
Page 65 and 66:
Heat source I RT-Lab II Specimen Ch
Page 67 and 68:
Thermal conductivity [W m -1 K -1 ]
Page 69 and 70:
silicon glue epoxy probe hole Figur
Page 71 and 72:
Computational modelling of temperat
Page 73 and 74:
1 2 3 EXT. INT. 5-15 50-60 375 5 Nu
Page 75 and 76:
Fig. 4 shows a comparison of the re
Page 77 and 78:
Envelope D Figs. 14, 15 present the
Page 79 and 80:
Application of computational modell
Page 81 and 82:
Table 2: Basic material characteris
Page 83 and 84:
Temperature [K] 320 300 280 260 240
Page 85 and 86:
Mineral wool has the same effect as
Page 87 and 88:
Nowadays, most of concrete building
Page 89 and 90:
Figure 2: Ceramic dessicator plate
Page 91 and 92:
dessicators are decreased by the pe
Page 93 and 94:
The surface water vapour diffusion
Page 95 and 96:
where h is the Planck constant and
Page 97 and 98:
(a) (b) Figure 2: Schematic picture
Page 99 and 100:
[7] BLUM, V.; HART, G. L. W.; WALOR
Page 101 and 102:
Analysis of moisture hysteresis of
Page 103 and 104:
The water content during scanning b
Page 105 and 106:
All analysed cellulose based materi
Page 107 and 108:
Thermodilatometry of ceramics using
Page 109 and 110:
of the dilatometric cell with the s
Page 111 and 112:
thermal expansion / % 2 1,5 1 0,5 0
Page 113 and 114:
[8] KAMSEU, E. ; LEONELLI, C. ; BOC
Page 115 and 116:
heating, the temperatures were meas
Page 117 and 118:
temperature difference [°C] 140 12
Page 119 and 120:
temperature difference [°C] 180 16
Page 121 and 122:
[4] ČÍČEL, B. - NOVÁK, I. - HOR
Page 123 and 124:
space and the crystallization press
Page 125 and 126:
20 mm face to the penetrating KNO3
Page 127 and 128:
Cb [kg/m 3 (sample)] 1800 1600 1400
Page 129 and 130:
D [m 2 /s] 1.0E-03 1.0E-04 1.0E-05
Page 131 and 132:
Thermomechanical modelling of matur
Page 133 and 134:
ε ε (velocity rates) a x , t . By
Page 135 and 136:
ε ε w v The process of redistribu
Page 137 and 138:
Conclusion In this paper we have br
Page 139 and 140:
most popular among direct technique
Page 141 and 142:
• Closed pores (not available for
Page 143 and 144:
espective volume of inclusions frac
Page 145 and 146:
Summary Among the indirect methods
Page 147 and 148: Thermal, hygric and salt‐related
Page 149 and 150: The water vapor diffusion coefficie
Page 151 and 152: Thermal properties Thermal conducti
Page 153 and 154: On the other hand, apparent moistur
Page 155 and 156: Thermal conductivity.. [Wm -1 K -1
Page 157 and 158: Properties of innovative materials
Page 159 and 160: or hygrothermal analysis of buildin
Page 161 and 162: where Da is the diffusion coefficie
Page 163 and 164: The bending and compressive strengt
Page 165 and 166: moisture diffusivity which was caus
Page 167 and 168: Abstract: Thermal conductivity in d
Page 169 and 170: , (5) where λ is thermal conductiv
Page 171 and 172: 4.Measured values and calculation I
Page 173 and 174: Acknowledgements This research has
Page 175 and 176: 3 Results During heating, the struc
Page 177 and 178: Acknowledgment This work was suppor
Page 179 and 180: mixture by short mixing, the mixtur
Page 181 and 182: detected by MIP and thus the intrus
Page 183 and 184: diffusion. The general Arrhenius eq
Page 185 and 186: Thermal conductivity measurement of
Page 187 and 188: S s o 2 4 4 λ ∇ T = wεσ ( T
Page 189 and 190: steel (20 W m ‐1 K ‐1 ) is arou
Page 191 and 192: significant larger cross‐section.
Page 193 and 194: Water and heat transport properties
Page 195 and 196: The open porosity ψ0 [%], bulk den
Page 197: Table 3: Basic material parameters
Page 201 and 202: comparison of results we can determ
Page 203 and 204: specimen and heat source R at infin
Page 205 and 206: 6.E-04 4.E-04 ΔU (V) 2.E-04 0.E+00
Page 207 and 208: [3] KUBIČÁR Ľ. Pulse method of m
Page 209 and 210: silicate binders as partial replace
Page 211 and 212: Table 2. Mechanical properties HPC
Page 213 and 214: HPC Table 5. Water transport proper
Page 215 and 216: The results obtained for using high
Page 217 and 218: aerospace engineering, cryogenic en
Page 219 and 220: 4 ⎡ ′ ⎤ Δθ( t) = ⎢ l ∫
Page 221 and 222: Alloy Components Weight Percent, [%
Page 223 and 224: Figure 8: Final results of the ther
Page 225 and 226: Figure 11: Preliminary results of t
Page 227 and 228: In case of the FeNi35, FeNi39 and F
Page 229 and 230: Experimental Methods Compressive st
Page 231 and 232: Type of mixture Water transport pro
Page 233 and 234: Thermal properties The thermal para
Page 235 and 236: Identification of Some Thermophysic
Page 237 and 238: Physical model of the direct proble
Page 239 and 240: 2 ( λ − Bi) sin( λ) − 2λ Bic
Page 241 and 242: To calculate the sensitivity coeffi
Page 243 and 244: symmetry of the specimen when the t
Page 245 and 246: Figure 5: View of experimental setu
Page 247 and 248: During the inverse calculations the
Page 249 and 250:
temperature dependence for the blac
Page 251 and 252:
4. Conclusions The results of the t
Page 253 and 254:
cross‐planar direction applying s
Page 255 and 256:
3. Thermal diffusivity identificati
Page 257 and 258:
Table 2: Effect of the convective h
Page 259 and 260:
[2] BODZENTA, J.; BURAKA, B.; NOWAK
Page 261 and 262:
doc. Ing. Jiří Vala, CSc. Brno Un
Page 263 and 264:
263
show all

Conference, Proceedings

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?