GemsHub
Model cement paste at elevated temperature #49
-
|
Hello. |
Beta Was this translation helpful? Give feedback.
Replies: 1 comment 3 replies
-
|
Dear @saeedsedighi1993 It is possible to model chemical transformations in GEMS at elevated temperatures. GEMS uses several methods to extrapolate the thermodynamic properties of substances or reactions at the desired T and P conditions. To be able to do this in calculations you need a thermodynamic database that contains all the phases that might form at these conditions with the input parameters for these methods. For cement modeling we mainly use cedmata18 database, but the calculations are limited to ~100C for most cement hydrate phases. This is due to lack of parameters but also lack of the other phases that may become stable at elevated temperatures, e.g. crystalline C-S-H. For doing calculations at 200-600 C you first need to find out what are the possible phases that might form, many of these are typical rock forming phases that are available in traditional geochemical databases (e.g. SUPCRT, MINES), but also other phases for which you need to compile the necessary thermodynamic properties and parameters. Once you compile the list of potential phases and complete properties you basically have a database based on which you can create a project and do calculations at different temperatures - then you can "model the chemical transformation of cement paste at elevated temperature". |
Beta Was this translation helpful? Give feedback.
-
|
I appreciate you for your guidance. According to the XRD results, the elevated temperature decomposes the main hydration products such as AFm, AFt. Only katotite can be formed at 300 Celsius degrees. I need a step step to step guidance for doing that project. Do you know any sources to learn how to model the chemical transformation at elevated temperatures.? A video or pdf file containing details of modeling and calculations can be helpful. |
Beta Was this translation helpful? Give feedback.
-
|
I would suggest to check the mines tutorials where the modeling is related to fluid rock interaction at elevated temperatures. The process is similar to your case. You can start with cemdata18 to create a project but remember that and you need the thermodynamic properties of phases that may form after the decomposition of the hydrates. If only katoite is of interest check that the method to calculate its properties with temperatures have the necessary parameters in GEMS (e.g., are there heat capacity coefficients, etc). You will see in the MINES tutorials examples of editing the database and adding new thermodynamic data. https://gemshub.github.io/site/community/materials/#fluidrock-interaction-hydrothermal |
Beta Was this translation helpful? Give feedback.
-
|
Thank you very much. I will start studying the tutorials. |
Beta Was this translation helpful? Give feedback.
Dear @saeedsedighi1993
It is possible to model chemical transformations in GEMS at elevated temperatures. GEMS uses several methods to extrapolate the thermodynamic properties of substances or reactions at the desired T and P conditions. To be able to do this in calculations you need a thermodynamic database that contains all the phases that might form at these conditions with the input parameters for these methods. For cement modeling we mainly use cedmata18 database, but the calculations are limited to ~100C for most cement hydrate phases. This is due to lack of parameters but also lack of the other phases that may become stable at elevated temperatures, e.g. crystalline C-S-H. For doin…