Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments
The early age volume changes occurring during the geopolymerisation reaction are not sufficiently understood yet, due to shortage of experimental data and theoretical models. This work presents new results on chemical and autogenous deformation of sodium-activated geopolymers from metakaolin, focuss...
Gespeichert in:
Veröffentlicht in: | Cement and concrete research 2021-06, Vol.144, p.106428, Article 106428 |
---|---|
Hauptverfasser: | , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
container_end_page | |
---|---|
container_issue | |
container_start_page | 106428 |
container_title | Cement and concrete research |
container_volume | 144 |
creator | Lolli, Francesca Thomas, Jeffrey J. Kurtis, Kimberly E. Cucinotta, Fabio Masoero, Enrico |
description | The early age volume changes occurring during the geopolymerisation reaction are not sufficiently understood yet, due to shortage of experimental data and theoretical models. This work presents new results on chemical and autogenous deformation of sodium-activated geopolymers from metakaolin, focussing on the first 72 h of reaction. The results show that the geopolymers undergo early-age chemical expansion, not shrinkage. A model is proposed to explain the experimental result, leveraging recent advances from molecular simulations. The model predicts how the extent of chemical expansion is controlled by confined water in the molecular structure of the geopolymer. However, despite this underlying chemical expansion, geopolymer samples undergo autogenous shrinkage at the macroscale, which excludes self-desiccation as the origin of autogenous deformation. A better insight is gained by monitoring the kinetics of geopolymerisation using isothermal and differential calorimetry. Two kinetic regimes are identified, with apparent activation energies of approximately 90 kJ/mol and 70 kJ/mol. This suggests that two microscopic mechanisms concur to determine the early-age volume changes of geopolymer pastes. |
doi_str_mv | 10.1016/j.cemconres.2021.106428 |
format | Article |
fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_journals_2536820580</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S0008884621000776</els_id><sourcerecordid>2536820580</sourcerecordid><originalsourceid>FETCH-LOGICAL-c458t-9266e1bc38a26aaa11abdf87decc94ec03949cbcd4959c4999eae6df720114633</originalsourceid><addsrcrecordid>eNqFUMtOwzAQtBBIlMI3YIlziu0krs2tqgpUqsQFzpbrbFKHxC52UtG_x1URV0770MzsziB0T8mMEsof25mB3ngXIM4YYTRtecHEBZpQMc-zXBbiEk0IISITouDX6CbGNo2c5WKCmpUO3RHrBvDBd2MP2Oy0ayBi63APg_7UvkttA37vu2MPIT7htYu22Q0R18H3uPcdmLHTAUfbpzpY7yLWrsLwvYdge3BDvEVXte4i3P3WKfp4Xr0vX7PN28t6udhkpijFkEnGOdCtyYVmXGtNqd5WtZhXYIwswJBkR5qtqQpZSlNIKUEDr-o5I5QWPM-n6OGsuw_-a4Q4qNaPwaWTipU5F4yUgiTU_IwywccYoFb79KcOR0WJOqWqWvWXqjqlqs6pJubizIRk4mAhqGgsOAOVDWAGVXn7r8YPPnyHUg</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>2536820580</pqid></control><display><type>article</type><title>Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments</title><source>Access via ScienceDirect (Elsevier)</source><creator>Lolli, Francesca ; Thomas, Jeffrey J. ; Kurtis, Kimberly E. ; Cucinotta, Fabio ; Masoero, Enrico</creator><creatorcontrib>Lolli, Francesca ; Thomas, Jeffrey J. ; Kurtis, Kimberly E. ; Cucinotta, Fabio ; Masoero, Enrico</creatorcontrib><description>The early age volume changes occurring during the geopolymerisation reaction are not sufficiently understood yet, due to shortage of experimental data and theoretical models. This work presents new results on chemical and autogenous deformation of sodium-activated geopolymers from metakaolin, focussing on the first 72 h of reaction. The results show that the geopolymers undergo early-age chemical expansion, not shrinkage. A model is proposed to explain the experimental result, leveraging recent advances from molecular simulations. The model predicts how the extent of chemical expansion is controlled by confined water in the molecular structure of the geopolymer. However, despite this underlying chemical expansion, geopolymer samples undergo autogenous shrinkage at the macroscale, which excludes self-desiccation as the origin of autogenous deformation. A better insight is gained by monitoring the kinetics of geopolymerisation using isothermal and differential calorimetry. Two kinetic regimes are identified, with apparent activation energies of approximately 90 kJ/mol and 70 kJ/mol. This suggests that two microscopic mechanisms concur to determine the early-age volume changes of geopolymer pastes.</description><identifier>ISSN: 0008-8846</identifier><identifier>EISSN: 1873-3948</identifier><identifier>DOI: 10.1016/j.cemconres.2021.106428</identifier><language>eng</language><publisher>Elmsford: Elsevier Ltd</publisher><subject>Activation energy ; Age ; Chemical shrinkage ; Expansion ; Geopolymers ; Metakaolin ; Molecular modelling ; Molecular structure ; Pastes ; Shrinkage</subject><ispartof>Cement and concrete research, 2021-06, Vol.144, p.106428, Article 106428</ispartof><rights>2021 Elsevier Ltd</rights><rights>Copyright Elsevier BV Jun 2021</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c458t-9266e1bc38a26aaa11abdf87decc94ec03949cbcd4959c4999eae6df720114633</citedby><cites>FETCH-LOGICAL-c458t-9266e1bc38a26aaa11abdf87decc94ec03949cbcd4959c4999eae6df720114633</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://dx.doi.org/10.1016/j.cemconres.2021.106428$$EHTML$$P50$$Gelsevier$$H</linktohtml><link.rule.ids>314,780,784,3550,27924,27925,45995</link.rule.ids></links><search><creatorcontrib>Lolli, Francesca</creatorcontrib><creatorcontrib>Thomas, Jeffrey J.</creatorcontrib><creatorcontrib>Kurtis, Kimberly E.</creatorcontrib><creatorcontrib>Cucinotta, Fabio</creatorcontrib><creatorcontrib>Masoero, Enrico</creatorcontrib><title>Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments</title><title>Cement and concrete research</title><description>The early age volume changes occurring during the geopolymerisation reaction are not sufficiently understood yet, due to shortage of experimental data and theoretical models. This work presents new results on chemical and autogenous deformation of sodium-activated geopolymers from metakaolin, focussing on the first 72 h of reaction. The results show that the geopolymers undergo early-age chemical expansion, not shrinkage. A model is proposed to explain the experimental result, leveraging recent advances from molecular simulations. The model predicts how the extent of chemical expansion is controlled by confined water in the molecular structure of the geopolymer. However, despite this underlying chemical expansion, geopolymer samples undergo autogenous shrinkage at the macroscale, which excludes self-desiccation as the origin of autogenous deformation. A better insight is gained by monitoring the kinetics of geopolymerisation using isothermal and differential calorimetry. Two kinetic regimes are identified, with apparent activation energies of approximately 90 kJ/mol and 70 kJ/mol. This suggests that two microscopic mechanisms concur to determine the early-age volume changes of geopolymer pastes.</description><subject>Activation energy</subject><subject>Age</subject><subject>Chemical shrinkage</subject><subject>Expansion</subject><subject>Geopolymers</subject><subject>Metakaolin</subject><subject>Molecular modelling</subject><subject>Molecular structure</subject><subject>Pastes</subject><subject>Shrinkage</subject><issn>0008-8846</issn><issn>1873-3948</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2021</creationdate><recordtype>article</recordtype><recordid>eNqFUMtOwzAQtBBIlMI3YIlziu0krs2tqgpUqsQFzpbrbFKHxC52UtG_x1URV0770MzsziB0T8mMEsof25mB3ngXIM4YYTRtecHEBZpQMc-zXBbiEk0IISITouDX6CbGNo2c5WKCmpUO3RHrBvDBd2MP2Oy0ayBi63APg_7UvkttA37vu2MPIT7htYu22Q0R18H3uPcdmLHTAUfbpzpY7yLWrsLwvYdge3BDvEVXte4i3P3WKfp4Xr0vX7PN28t6udhkpijFkEnGOdCtyYVmXGtNqd5WtZhXYIwswJBkR5qtqQpZSlNIKUEDr-o5I5QWPM-n6OGsuw_-a4Q4qNaPwaWTipU5F4yUgiTU_IwywccYoFb79KcOR0WJOqWqWvWXqjqlqs6pJubizIRk4mAhqGgsOAOVDWAGVXn7r8YPPnyHUg</recordid><startdate>202106</startdate><enddate>202106</enddate><creator>Lolli, Francesca</creator><creator>Thomas, Jeffrey J.</creator><creator>Kurtis, Kimberly E.</creator><creator>Cucinotta, Fabio</creator><creator>Masoero, Enrico</creator><general>Elsevier Ltd</general><general>Elsevier BV</general><scope>AAYXX</scope><scope>CITATION</scope><scope>7QQ</scope><scope>7SR</scope><scope>8BQ</scope><scope>8FD</scope><scope>FR3</scope><scope>JG9</scope><scope>KR7</scope></search><sort><creationdate>202106</creationdate><title>Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments</title><author>Lolli, Francesca ; Thomas, Jeffrey J. ; Kurtis, Kimberly E. ; Cucinotta, Fabio ; Masoero, Enrico</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c458t-9266e1bc38a26aaa11abdf87decc94ec03949cbcd4959c4999eae6df720114633</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2021</creationdate><topic>Activation energy</topic><topic>Age</topic><topic>Chemical shrinkage</topic><topic>Expansion</topic><topic>Geopolymers</topic><topic>Metakaolin</topic><topic>Molecular modelling</topic><topic>Molecular structure</topic><topic>Pastes</topic><topic>Shrinkage</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Lolli, Francesca</creatorcontrib><creatorcontrib>Thomas, Jeffrey J.</creatorcontrib><creatorcontrib>Kurtis, Kimberly E.</creatorcontrib><creatorcontrib>Cucinotta, Fabio</creatorcontrib><creatorcontrib>Masoero, Enrico</creatorcontrib><collection>CrossRef</collection><collection>Ceramic Abstracts</collection><collection>Engineered Materials Abstracts</collection><collection>METADEX</collection><collection>Technology Research Database</collection><collection>Engineering Research Database</collection><collection>Materials Research Database</collection><collection>Civil Engineering Abstracts</collection><jtitle>Cement and concrete research</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Lolli, Francesca</au><au>Thomas, Jeffrey J.</au><au>Kurtis, Kimberly E.</au><au>Cucinotta, Fabio</au><au>Masoero, Enrico</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments</atitle><jtitle>Cement and concrete research</jtitle><date>2021-06</date><risdate>2021</risdate><volume>144</volume><spage>106428</spage><pages>106428-</pages><artnum>106428</artnum><issn>0008-8846</issn><eissn>1873-3948</eissn><abstract>The early age volume changes occurring during the geopolymerisation reaction are not sufficiently understood yet, due to shortage of experimental data and theoretical models. This work presents new results on chemical and autogenous deformation of sodium-activated geopolymers from metakaolin, focussing on the first 72 h of reaction. The results show that the geopolymers undergo early-age chemical expansion, not shrinkage. A model is proposed to explain the experimental result, leveraging recent advances from molecular simulations. The model predicts how the extent of chemical expansion is controlled by confined water in the molecular structure of the geopolymer. However, despite this underlying chemical expansion, geopolymer samples undergo autogenous shrinkage at the macroscale, which excludes self-desiccation as the origin of autogenous deformation. A better insight is gained by monitoring the kinetics of geopolymerisation using isothermal and differential calorimetry. Two kinetic regimes are identified, with apparent activation energies of approximately 90 kJ/mol and 70 kJ/mol. This suggests that two microscopic mechanisms concur to determine the early-age volume changes of geopolymer pastes.</abstract><cop>Elmsford</cop><pub>Elsevier Ltd</pub><doi>10.1016/j.cemconres.2021.106428</doi><oa>free_for_read</oa></addata></record> |
fulltext | fulltext |
identifier | ISSN: 0008-8846 |
ispartof | Cement and concrete research, 2021-06, Vol.144, p.106428, Article 106428 |
issn | 0008-8846 1873-3948 |
language | eng |
recordid | cdi_proquest_journals_2536820580 |
source | Access via ScienceDirect (Elsevier) |
subjects | Activation energy Age Chemical shrinkage Expansion Geopolymers Metakaolin Molecular modelling Molecular structure Pastes Shrinkage |
title | Early age volume changes in metakaolin geopolymers: Insights from molecular simulations and experiments |
url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-01-01T18%3A55%3A23IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Early%20age%20volume%20changes%20in%20metakaolin%20geopolymers:%20Insights%20from%20molecular%20simulations%20and%20experiments&rft.jtitle=Cement%20and%20concrete%20research&rft.au=Lolli,%20Francesca&rft.date=2021-06&rft.volume=144&rft.spage=106428&rft.pages=106428-&rft.artnum=106428&rft.issn=0008-8846&rft.eissn=1873-3948&rft_id=info:doi/10.1016/j.cemconres.2021.106428&rft_dat=%3Cproquest_cross%3E2536820580%3C/proquest_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=2536820580&rft_id=info:pmid/&rft_els_id=S0008884621000776&rfr_iscdi=true |