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CemGEMS web app


Here we provide information about relevant changes from release to release, starting from v.0.4.0 beta, which is the first version of CemGEMS with unassisted user registration and streamlined workflow.

v.0.6.1, March 19, 2021

  • Corrections and extensions release: the 5-parameter logistic function (5PL) models for different clinker or SCM constituents are extended onto all 10 main cement types (for "min" data type), with the Hydration-5PL-AC process variant to be used with calcium (sulfo)aluminate cements only.

  • All hydration vs time process templates were updated after the harmonization of consitituents in template recipes. See materials-constituents-lists page for details. To fully benefit from these changes, we recommend to clean up once the application memory in the browser as described in the troubleshooting page. Your existing recipes, processes and plots will not be affected.

  • The phasesAliases table header and design improved in order to reduce the confusion about what phases are suppressed and what not in the equilibrated part of the recipe results.

  • Improved many tutorial pages by converting some lists into tables, making some links open in separate browser tabs, and adding documentation tables with constituents lists and the cement chemistry notation.

v.0.6.0, February 16, 2021

  • Extended functionality release: simulation of time-dependent cement hydration is now possible using either modified Parrot-Killoh (mP&K) or 4-m or 5-parameter logistic function (5PL) models for different clinker or SCM constituents in the same process. See redefining-processes page for details.

  • Cleaned recipe- and process templates from unused or obsolete data fields, added or corrected more recipe data, legend colors etc. Fixed issues in using specific surface areas of solids in mP&K simulations. Fixed the normalization of heat rates to the mass of cement instead of the mass of binder, and the use of equilibrated recipe heat capacity for computing adiabatic temperature rise.

  • Rearranged GEMS3K init files and JSON documents, made PT grid 4x26 default DCH file with thermodynamic data, elements, phases and species lists. xGEMS/GEMS3K now initializes from 3 JSON documents uploaded into the template database, where it is easy to check/fix.

  • Front-end: modularized all plot types, fixed rendering of tables and plots in Safari and Firefox browsers. Back-end: more secure monitoring of ArangoDB state with automatic restart when needed.

v.0.5.3, January 8, 2021

  • Bugfix release: In the GEMSW code, implemented a deep cleaning of Volume, bcMass and bcObject entities upon zeroing off a material or constituent Quantity.

  • Minor additions and corrections in recipe, phaseAliases and legend templates. A more conservative default selection of suppressed phases in phaseAliases table for better stability of GEM calculations.

  • Plot for processes: now allows a zoomed interval rendered both into the data table and in the main plot canvas (except stacked bar charts).

v.0.5.2, December 30, 2020

  • Bugfix release (fixes in rendering in tree-like tables, "Residual" table when no residual is present in the recipe).

  • Corrections in GEMSW backend code (processing of recipe-level formula list, normalization of percentages in formula lists, cleaning of unused objects in residual part, calculation of heat effects).

  • Numerous improvements and corrections in recipe-, process- and other templates; improved rendering of tree-like tables and plotting of Aqueous-Totals.

  • It is now possible to equilibrate "minimal" recipes, e.g. those composed only from CaO, SiO2 and H2O. "Minimal" and "Primitive" recipe templates facilitate this for didactic purposes.

  • Added two "Minimal" recipe templates composed of materials without constituents, with compositions defined via material-level formula lists (most processes can run from such parent recipes).

  • Added two "Primitive" recipe templates without materials and constituents, with bulk hydrated cement composition defined via a recipe-level formula list (most processes are disabled for such parent recipes).

  • Extended the applicability of 4PL hydration model ("Hydration-4PL" process) to parent recipes made of all templates (of "min" data type) except CEM-I-xx, Minimal and Primitive.

v.0.5.1, December 21, 2020

  • Fixed plots for isothermal and adiabatic heat effects.

  • Fixed bugs in GEMSW back-end code in calculations of heat effects in certain cases; adjusted correction factors for estimating adiabatic temperature rise.

  • Fixed many templates, especially adding the missing thermochemical data to recipe templates.

  • In "Ingress" process templates, made the compensatory removal of CaO upon addition of Salts optional.

  • Changed default phaseAliases template (selection of suppressed and allowed phases).

v.0.5.0, November 24, 2020

  • Implemented calculations of isothermal heat effects of cement hydration (Nanocem project extension). Both heat generation rate and cumulative heat are computed and plotted.

  • The standard specific enthalpies and heat capacities for clinker phases and SCMs are now automatically collected from GEMS internal data, wherever possible.

  • Implemented approximative estimates of possible adiabatic temperature rise, as the rate and the cumulative temperature (both are plotted for hydration processes).

  • Implemented an alternative cement hydration kinetics process model based on 4PL (5PL) logistic equations for CSA cements.

  • Re-implemented 'ingress' process templates for simulating carbonation or salt ingress, which now yield more realistic qualitative diagrams (especially for carbonation) because of the compensative removal of calcium and hydroxyl and the optional continued reaction of clinker or SCMs.

  • Added recently published thermodynamic data for zeolites (Ma, Lothenbach, Cem. Con. Res. 135 (2020), 106149) and phosphates (Lothenbach, Xu, Winnefeld, Appl. Geochem. 111 (2019), 104450) to GEMS input thermodynamic data files.

  • Checked, fixed and enhanced the input data in most of template cement recipes. Updated the default list of suppressed phases in phaseAliases table; fixed GEMS3K input files.

  • Improved some process templates and plot axis definitions; renamed the chart type 'StackedAreaLines' to 'StackedAreas'; improved the documentation for processes and plots.

  • Removed the "engineer" level from the tutorial and view option from the front-end (the descriptions in this tutorial were split between the "student" and the "expert" levels).

  • Upgraded CemGEMS web app server to Centos 8 and ArangoDB 3.7, implemented the automated dump and restore of the server database, with many other improvements on the DevOps side.

  • Substantially improved the look-and-feel of the front-end window and widgets (CSS styles of tree-like table rendering, plots, jsoneditor; table blueprints, etc.).

  • Implemented automatic clean-up of the web browser memory upon upgrade from the lower version (new features are available only for newly-created recipes, processes and plots).

v.0.4.2, August 3, 2020

  • Fixed a technical debt in GEMSW processing of quantities of constituents and formulae in mole amount or mole fraction units. However, quantities of materials and of the whole recipe can only be provided in mass units (g, kg, mg) because of pre-processing W/B ratios (otherwise, the units will be changed to g (grams)).

  • Upon GEMS failure in simulation of a new process, the new process document is now available for editing using jsoneditor, which allows an expert user to fix it and run the process completely.

  • Other minor bugfixes, more error detection and error messages.

v.0.4.1, June 30, 2020

  • Added a plot template "Aqueous-pH-pe-Eh-IS", improved process and recipe templates ("Calcite" constituent in "Cement" material is now "CaCO3").

  • Fixed bugs in templates resulting in wrong legend colors in horisontal and 2-D stacked bar charts for some cement recipes (e.g. LC3).

  • Fixed a glitch preventing the normal operation of CemGEMS web app for user names with period '.' (e.g. john.smith).

v.0.4.0 beta, June 22, 2020

The first release of CemGEMS with unassisted user registration and streamlined workflow (for beta-testing).

Last update: March 19, 2021