Effects of LiAl-layered double hydroxides on early hydration of calcium sulphoaluminate cement paste

• DOI: 10.1007/s11595-017-1717-4
• Publication Date: 2017-10-06T11:35:53Z
• Authors: Haiyan Li; Xuemao Guan; Lei Yang; Songhui Liu; Jianwu Zhang; Yanan Guo
• Keywords: 02 engineering and technology; 0210 nano-technology

As a 3D micro-nano material, layered double hydroxides have been widely used in many fields, especially for reinforced composite materials. In this paper, LiAl-LDHs was obtained by a hydrothermal method. In order to investigate the effects of LiAl-LDHs on the early hydration of calcium sulphoaluminate (CSA) cement paste, compressive strength, setting time and hydration heat were tested while X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scaning electron microscopy (SEM) and differential scanning calorimetry (DSC) analysis were employed. The results indicated that LiAl-LDHs could significantly improve the early compressive strength and shorten the setting time of calcium sulphoaluminate cement paste with 3wt% concentration. Besides, the hydration exothermic rate within 5 h was accelerated with increasing LiAl-LDHs content. Moreover, the addition of LiAl-LDHs did not result in the formation of a new phase, but increased the quantity of hydration products providing higher compressive strength, shorter setting time and denser microstructure.