红土含量对古建红灰性能的影响及作用机制

Influence of Red Clay Content on the Performance of Red Lime Using in Ancient Buildings and Its Mechanism

摘要:

制备了一定梯度红土含量的红灰样品，通过物理力学性能测试、冻融循环试验分析了红土含量对红灰性能的影响，并采用X射线衍射（XRD）、红外光谱（FTIR）、扫描电子显微镜（SEM）等技术探究了红土的作用机制.结果表明：添加红土后，红灰的防水性、力学性能与耐冻融性均得到改善；红灰中红土与Ca（OH）₂发生了火山灰反应，生成的水化硅酸钙填充在红灰孔隙中，提高了其结构的致密性；随着红土掺量的增加，红灰的碳化速率加快，有利于其早期强度的提升.

Abstract:

Red lime samples with a certain gradient of red clay contents were prepared. The influence of red clay contents on the performance of the red limes was analyzed through physical and mechanical performance tests and freeze-thaw cycle tests. The mechanism of action of red clay was explored by X-ray diffraction （XRD）， infrared spectroscopy （FTIR）， scanning electron microscope （SEM） and other techniques. The results show that after adding red clay， the water resistance， mechanical properties and freeze-thaw resistance of the redtime are improved. In the red lime， the pozzolanic reaction occurs in the red clay and Ca（OH）₂， and the hydrated calcium silicate produced is filled in the pores of the red lime， with the result that the compactness of its structure is improved. With the increase of red clay content， the carbonation rate of red clay accelerates， resulting in the improvement of the early strength.