Hygric properties of porous building materials (V): Comparison of different methods to determine moisture diffusivity

This paper compares the X-ray method, the ruler method and the multi-step method to non-destructively determine the moisture diffusivity of calcium silicate and ceramic brick. Results show that the ruler method and multi-step method produce acceptable diffusivities and λ-profiles compared with the common X-ray method, meaning that both methods can determine moisture diffusivity reliably to some extent without the expensive X-ray setup and complicated data processing.

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A round robin campaign on the hygric properties of porous building materials

MATEC Web of Conferences ◽

10.1051/matecconf/201928202011 ◽

2019 ◽

Vol 282 ◽

pp. 02011 ◽

Cited By ~ 1

Author(s):

Chi Feng ◽

Ana Sofia Guimarães ◽

Nuno Ramos ◽

Lixin Sun ◽

Dariusz Gawin ◽

...

Keyword(s):

Building Materials ◽

Round Robin ◽

Capillary Absorption ◽

Reliable Determination ◽

Porous Building Materials ◽

Vacuum Saturation ◽

Experimental Protocols ◽

Hygric Properties ◽

Data Processing Methods

The reliable determination of the hygric properties of porous building materials is important. In earlier round robin campaigns large discrepancies of measured hygric properties were found among different labs. Later studies indicated that differences in lab conditions and more importantly, personnel’s operation procedures and data processing methods, might have the greatest impact. To gain further insight, a new round robin campaign has been launched by KU Leuven (Belgium), to which another eight institutes contributed. A relatively stable and homogeneous ceramic brick is tested, and 3 standard tests are performed: the vacuum saturation test, the capillary absorption test and the cup test. During the campaign, two rounds of measurements are performed. In the 1st round, tests are performed according to participants’ respective experimental protocols. Next, a strict and detailed common protocol is prescribed. This paper reports on the results obtained in the 1st round of measurements. Results show that not much progress has been made since the EC HAMSTAD project: the vacuum saturation test leads to the most consistent results, while the cup test produces the largest discrepancies, most probably originating from sample sealing and humidity control.

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Hygric properties of porous building materials (VII): Full-range benchmark characterizations of three materials

Building and Environment ◽

10.1016/j.buildenv.2021.107727 ◽

2021 ◽

Vol 195 ◽

pp. 107727

Author(s):

Chi Feng ◽

Hans Janssen

Keyword(s):

Building Materials ◽

Full Range ◽

Porous Building Materials ◽

Hygric Properties

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Hygric properties of porous building materials (IV): Semi-permeable membrane and psychrometer methods for measuring moisture storage curves

Building and Environment ◽

10.1016/j.buildenv.2019.01.054 ◽

2019 ◽

Vol 152 ◽

pp. 39-49 ◽

Cited By ~ 2

Author(s):

Chi Feng ◽

Hans Janssen

Keyword(s):

Building Materials ◽

Permeable Membrane ◽

Porous Building Materials ◽

Moisture Storage ◽

Hygric Properties

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Hygric properties of porous building materials (III): Impact factors and data processing methods of the capillary absorption test

Building and Environment ◽

10.1016/j.buildenv.2018.02.038 ◽

2018 ◽

Vol 134 ◽

pp. 21-34 ◽

Cited By ~ 17

Author(s):

Chi Feng ◽

Hans Janssen

Keyword(s):

Data Processing ◽

Building Materials ◽

Impact Factors ◽

Capillary Absorption ◽

Absorption Test ◽

Processing Methods ◽

Porous Building Materials ◽

Hygric Properties ◽

Data Processing Methods

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Comparison of Two Different Modes of Inverse Analysis Used for Determination of Moisture Diffusivity of Building Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.982.49 ◽

2014 ◽

Vol 982 ◽

pp. 49-53 ◽

Cited By ~ 2

Author(s):

Jan Kočí ◽

Zbyšek Pavlík ◽

Robert Černý

Keyword(s):

Genetic Algorithms ◽

Laboratory Experiment ◽

Inverse Analysis ◽

Building Materials ◽

Moisture Diffusivity ◽

Inverse Methods ◽

Short Discussion ◽

Porous Building Materials

This paper gives a brief overview of two different approaches within the inverse analysis used for determination of moisture diffusivity of porous building materials. The inverse methods are represented by Boltzman-Matano approach and genetic algorithms. Both methods are described in this paper and its application is demonstrated on a simple laboratory experiment. Finally, the results of both treatments are compared together and short discussion is given.

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