Abstract

Nowadays, concretes with better mechanical properties and durability are required, in order to develop structures with higher mechanical requirements and to resist construction aggressive environments. Following from that, the addition of superabsorbent polymers (SAP) as a method of internal curing in concrete, could provide a greater degree of hydration of the cement, reducing cracks generated by the self-drying of the paste, and improving concrete stability. However, the process of absorption in more complex cementitious systems has not yet been reviewed. In this investigation composite materials with and without SAP additions and with different degrees of substitution using supplementary cementitious materials were studied with the main goal to evaluate the development of the SAP additions in these complex composites. In order to analyze the hydration reactions, microstructure and mechanical behavior several tests were carried out as: compression strength, X-ray diffraction, isothermal calorimetry, scanning electron microscopy, and energy dispersion spectroscopy. The results obtained showed that the presence of SAP modified the rheology of concrete mixtures, and in some cases delaying pozzolanic reaction of the systems, having limited effects on the improvement of mechanical properties.

摘要

如今，需要具有更好机械性能和耐久性的混凝土，以开发具有更高机械要求的结构并抵抗施工侵蚀性环境。在此之后，添加高吸水性聚合物 (SAP) 作为混凝土内部固化的一种方法，可以提供更大程度的水泥水化，减少由浆体自干产生的裂缝，并提高混凝土稳定性。然而，尚未审查在更复杂的水泥体系中的吸收过程。在这项研究中，研究了添加和不添加 SAP 以及使用辅助胶凝材料进行不同程度替代的复合材料，主要目的是评估这些复杂复合材料中添加 SAP 的情况。为了分析水合反应、微观结构和机械行为，进行了多项测试：压缩强度、X 射线衍射、等温量热法、扫描电子显微镜和能量色散光谱。获得的结果表明，SAP 的存在改变了混凝土混合物的流变性，并且在某些情况下延迟了系统的火山灰反应，对改善力学性能的影响有限。