Fast Inverse-Analysis Calculation of Diffusion Coefficient for Salt Transport in Porous Building Materials

2015 ◽  
Vol 1126 ◽  
pp. 117-122 ◽  
Author(s):  
Igor Medveď ◽  
Zbyšek Pavlík ◽  
Milena Pavlíková ◽  
Robert Černý
Keyword(s):  
Diffusion Coefficient ◽  
Inverse Analysis ◽  
Analytical Approach ◽  
Building Materials ◽  
Salt Transport ◽  
Porous Building Materials ◽  
Advection Diffusion ◽  
Analysis Calculation ◽  
Salt Diffusion

An analytical approach to the determination of a varying salt diffusion coefficient is discussed. It is argued that the approach is fast and reliable and can be very convenient in various civil engineering applications dealing with the transport of salts in porous building materials. The advection-diffusion model of Bear and Bachmat is used to describe the salt transport, and the Bolztmann-Matano inverse analysis is applied to calculate the salt diffusion coefficient. Possible extensions to other models of transport are pointed out. The results are applied to a sandstone from the Msene quarry, Czech Republic.

scholarly journals Role of Time Relaxation in a One-Dimensional Diffusion-Advection Model of Water and Salt Transport

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Igor Medved’ ◽  
Robert Černý
Keyword(s):  
Diffusion Coefficient ◽  
Structural Damage ◽  
Building Materials ◽  
Chloride Transport ◽  
Salt Transport ◽  
One Dimensional ◽  
Advection Diffusion ◽  
Dimensional Diffusion ◽  
Lime Plaster

The transport of salt, necessarily coupled with the transport of water, through porous building materials may heavily limit their durability due to possible deterioration and structural damage. Usually, the binding of salt to the pore walls is assumed to occur instantly, as soon as the salt is transported by water to a given position. We consider the advection-diffusion model of the transport and generalize it to include possible delays in the binding. Applying the Boltzmann-Matano method, we calculate the diffusion coefficient of the salt in dependence on the salt concentration and show that it increases with the rate of binding. We apply our results to an example of the chloride transport in a lime plaster.

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

2014 ◽  
Vol 982 ◽  
pp. 49-53 ◽  
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.

Salt transport and crystallization in porous building materials

2003 ◽  
Vol 21 (3-4) ◽  
pp. 317-320 ◽  
Author(s):  
L. Pel ◽  
H. Huinink ◽  
K. Kopinga
Keyword(s):  
Building Materials ◽  
Salt Transport ◽  
Porous Building Materials

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

2019 ◽  
Vol 282 ◽  
pp. 02011 ◽  
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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