Reducing Ettringite- and Thaumasiteformation in damaged sulfate containing Masonry

减少受损的含硫酸盐砌体中钙矾石和硅灰石的形成

• 批准号: 230660215
• 负责人: Professor Dr.-Ing. Horst-Michael Ludwig
• 金额: --
• 依托单位: F. A. Finger-Institut für Baustoffkunde
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/230660215?language=en
• 关键词: Reducing; Ettringite; Thaumasiteformation; damaged; sulfate

During the maintenance of sulfate containing masonry still serious mistakes are made today. One reason for this is the fact, that for many of those measures practicable solutions for maintenance are missing. So for example the inserting of water by conventional injections in those masonries does not only show that damaging reaction cannot be stopped, but also lead to less capacity of the masonry. Preliminary tests have shown that it is possible to suppress a further volume expansion by inserting silica acid ester. The silica acid ester will be inserted in its liquid form without adding water, which ensures that neither slide can take place nor loss of resistance will occur caused by a moisture penetration of the sulfate containing material. The exact mechanisms of action of the silica acid ester as well as the essential parameters for its effectiveness are not known yet. It is expected that due to the polycondensation of the silica acid ester reactive silicon is available, which allows the formation of secondary C-S-H phases with the existing calciumhydroxid. They stabilize the structure and reduce the Portlanditcontent (Ca/Si-ratio) of the hydraulic material. As a result of this a higher sulfate resistance is expected. In the work program chemical/mineralogical and physical aspects of the silica acid ester usage are investigated to prepare the use of those materials in practice. The usage of optimized silica acid ester-material on a test object is planned.

在维持含有砌体的硫酸盐期间，今天仍然犯了严重的错误。原因之一是事实是，对于许多这些措施，可行的维护解决方案都缺失了。因此，例如，在这些砌体中，通过常规注射插入水不仅表明破坏性反应不能停止，而且还会导致砌体的容量较小。初步测试表明，可以通过插入二氧化硅酸酯来抑制进一步的体积扩张。二氧化硅酸酯将在不加水的情况下以其液态插入，这确保载玻片不能发生，也不会因含硫酸盐含有材料的水分渗透而导致耐药性丧失。硅酸酯的确切作用机理以及其有效性的基本参数尚不清楚。可以预期，由于硅酸酯反应性硅的多浓度，可以使用现有的钙羟基氧化二次C-S-H相。他们稳定结构并减少液压材料的portlanditcontent（Ca/si-ratio）。因此，预计将具有较高的硫酸盐耐药性。在工作计划中，研究了硅酸酯使用​​的化学/矿物学和物理方面，以准备在实践中使用这些材料。计划在测试对象上使用优化的硅酸酯材料。