Moisture dynamics in walls: response to micro-environment and climate change
Moisture dynamics in walls: response to micro-environment and climate change
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DOI：
10.1098/rspa.2010.0131
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发表时间：
2011-01
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影响因子：
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通讯作者：
C. Hall;A. Hamilton;W. D. Hoff;H. Viles;J. Eklund
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文献类型：
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作者：
C. Hall;A. Hamilton;W. D. Hoff;H. Viles;J. Eklund
耦合锐锋 (SF) 液体传输和蒸发模型用于描述整料和砖石结构中水分的毛细管上升。这为此类结构中水分动态的定量工程分析提供了基础，特别适用于历史建筑和古迹的保护。我们利用英格兰南部和希腊雅典的气象数据展示了这样的系统如何响应直接环境潜在蒸发量 (PE) 的季节性变化。将 SF 分析模型的结果与有限元非饱和流模拟的结果进行比较。我们检查通过结构的总流量的大小和变化，将其作为浸出、盐结晶和化学降解造成的长期损害的主要因素。我们发现水分上升高度的季节性变化很大，这与估计的大量水流量一起为观察到的盐结晶损害位置提供了新的解释。该分析还使我们能够估计未来气候变化对巨石和砌体结构的毛细管湿度动态的影响。例如，对于英格兰南部，预测 2070 年至 2100 年期间 PE 的增加表明水通量大幅增加，因此我们预计损害率会增加。
A coupled sharp-front (SF) liquid transport and evaporation model is used to describe the capillary rise of moisture in monoliths and masonry structures. This provides a basis for the quantitative engineering analysis of moisture dynamics in such structures, with particular application to the conservation of historic buildings and monuments. We show how such a system responds to seasonal variations in the potential evaporation (PE) of the immediate environment, using meteorological data from southern England and Athens, Greece. Results from the SF analytical model are compared with those from finite-element unsaturated-flow simulations. We examine the magnitude and variation of the total flow through a structure as a primary factor in long-term damage caused by leaching, salt crystallization and chemical degradation. We find wide seasonal variation in the height of moisture rise, and this, together with the large estimated water flows, provides a new explanation of the observed position of salt-crystallization damage. The analysis also allows us to estimate the effects of future climate change on the capillary moisture dynamics of monoliths and masonry structures. For example, for southern England, predicted increases in PE for the period 2070–2100 suggest substantial increases in water flux, from which we expect increased damage rates.