高温环境下碳硫硅钙石-钙矾石固溶体的研究

Research of Thaumasite-Ettringite Solid Solution at High Temperatures

由碳硫硅钙石引起的硫酸盐侵蚀破坏在许多国家都有相关工程案例。铝相可以加速碳硫硅钙石的生成,并能够与钙矾石形成固溶体,但铝相的作用机理目前尚无定论。在不同温度下合成了一系列固溶体,并利用XRD,SEM-EDS及红外对固溶体进行了测试分析,结果表明:40℃温度下亦可以生成碳硫硅钙石/固溶体;20℃与40℃均能够形成碳硫硅钙石型与钙矾石型两种形态固溶体;a轴固溶体间隙随温度升高而增大,20℃环境下固溶体间隙为1.1076~1.1182 nm,40℃时固溶体间隙为1.1069~1.1189 nm;随温度升高碳硫硅钙石-钙矾石固溶体晶体形貌更加细长。

There has been much reported recently on the occurrence of thaumasite of sulfate attack in concrete in many countries. Research has shown that this process can be accelerated by aluminum phases and form thaumasite-ettringite solid solution,but the specific mechanism is uncertain. A series of solid solution phases have been prepared and analysed by XRD,SEM-EDS and FTIR. Results indicate：thaumasite/solid-solution can also form at 40 ℃; thaumasite types and ettringite types solid solution are formed in all samples; the gap in the a-dimensions is increased with the increasing of temperature,the gap in the a-dimensions is 1. 1076-1. 1182 nm at 20 ℃ and the gap is 1. 1069-1. 1189 nm at 40 ℃; the morphologies is more long and thin when the temperature increased.