A chemo-mechanical model of lime hydration in concrete structures

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• 作者：Bernardino Chiaia¹ ; ^{bernardino.chiaia@polito.it} ; Alessandro P. Fantilli ; ^{alessandro.fantilli@polito.it} ; Giulio Ventura² ; ^{giulio.ventura@polito.it}
• 关键词：Free lime ; Finite element analysis ; Chemo-mechanical model ; Concrete shrinkage
• 刊名：Construction and Building Materials
• 出版年：2012
• 出版时间：April 2012
• 年：2012
• 卷：29
• 期：Complete
• 页码：308-315
• 全文大小：1221 K

文摘

A size-effect theory is herein introduced to investigate the average expansion of concrete containing free lime (CaO) and impurities. By drawing an analogy with the structural size-effect, the phenomenon of CaO hydration shows a characteristic length, whose dimension remains constant at all scales. If a grain of free lime is assumed to be a sphere, only a thin layer on the external surface hydrates and doubles the volume, as confirmed by the results of 2D finite element analyses and by some experimental observations. For practical applications, a simplified chemo-mechanical model of CaO hydration is eventually proposed, to predict the consequences of uncombined lime in concrete structures.