This paper presents measurements of the moisture storage capacity for several different porous building materials. The storage capacity is measured by a sorption balance in the hygroscopic range and with pressure plate and pressure membrane extractors in the superhygroscopic range. The results are presented both as retention curves and sorption isotherms and indicate, among other things, that some materials have a large hysteresis between absorption and desorption in the superhygroscopic range. This is contrary to what sometimes has been postulated.
Fagerlund, G.
(1999), “Hysteresis between pore water pressure and moisture content: Conse- quences of drying shrinkage and frost resistance”(in Swedish), Report TVBM-7138, Division of Building Materials, Lund Institute of Technology, Lund.
2.
Letey, J.
, Osborn, J. and Pelishek, R. E. (1962), “Measurement of liquid–solid contact angles in soil and sand,”Soil Science, Vol. 93, No. 3, pp. 149—153.
3.
Wadsö, I.
and Wadsö, L. (1996), “Anewmethod for determination of vapour sorption isotherms using a twin double microcalorimeter,”Thermochimica Acta, Vol. 271, pp. 179–187.
4.
Wadsö, I.
and Wadsö, L. (1997), “A second generation twin double microcalorimeter: Measurements of sorption isotherms, heats of sorption and sorption kinetics,”Journal of Thermal Analysis, Vol. 49, pp. 1045–1052.
5.
Wadsö, L.
(1997), “Areviewof methods to measure sorption isotherms and heats of sorption,” paper presented at the International Conference on Wood–Water Relations, Copenhagen, 16–17 June.
6.
Nordtest Standard
. (1997), “Retention curve and pore size distribution,” NT BUILD 481.
7.
Krus, M.
and Kießl, K. (1991), “An experimental comparison between pore size distributions obtained with mercury porosimetry and pressure extractors”(in German), Report FtB-11, Fraunhofer-Institut für Bauphysik, Holzkirchen, Germany.
8.
Fagerlund, G.
(1973), “Determination of pore size distribution from freezing-point depression,”Materials and Structures, Vol. 6, No. 33, pp. 215–225.
9.
Fagerlund, G.
(1973), “Determination of pore size distribution by suction porosimetry,”Materials and Structures, Vol. 6, No. 33, pp. 191–201.
10.
Lindborg, U.
(1990), “Air pollution and the cultural heritage: Action plan 90”, Report RIK 1, The Central Board of National Antiquities and the National Historical Museum, Stockholm, Sweden.
11.
Fagerlund, G.
(1977), “The critical degree of saturation method of assessing the freeze/thaw resistance of concrete,”Materials and Structures, Vol. 10, No. 58.
12.
Richards, L. A.
(1948), “Porous plate apparatus for measuring moisture retention and transmission by soil,”Soil Science, Vol. 66, pp. 105–109.
13.
Krus, M.
(1995), “Moisture transport and storage coefficients of porous mineral building materials: Theoretical principles and new test methods”(in German), Der Fakultät Bauingenieurund Vermessungswesen der Universität Stuttgart.
14.
Janz, M.
(1997), “Methods of measuring the moisture diffusivity at high moisture levels”, Report TVBM-3076, Division of Building Materials, Lund Institute of Technology, Lund.
15.
Wessman, L.
(1997), “Studies on the frost resistance of natural stone”, Report TVBM-3077, Division of Building Materials, Lund Institute of Technology, Lund.
16.
Penner, E.
(1965), “Suction and its use as measure of moisture contents and potentials in porous materials,”Humidity and Moisture, Vol. 4, Reinhold Publ. Co., New York.
