Study of metakaolin geopolymer composites reinforced by clean broom-like bristle bamboo fibers

Abstract

Natural fiber-reinforced geopolymer (GP) is gaining popularity in the construction and building materials industries due to its natural renewability, accessibility, low cost, and excellent mechanical properties. In light of this, an investigation was conducted on the effect of bamboo fiber (BF) loading and fiber pretreatment methods on final composites. Mechanical tests showed that compared to pure GP, the compressive strength and flexural strength of GP composites were slightly negatively affected by the addition of either untreated or alkali-treated BFs. However, the loading of KH550 significantly improved the mechanical properties of GP with the addition of alkali-treated BFs more than untreated BFs. Scanning electron microscopy (SEM) analysis illustrated that the employment of KH550 effectively improved the interfacial performance between the BF and GP matrix. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) tests demonstrated the successful synthesis of GP and that the addition of KH550 had little effect on the main crystal structure and chemical composition of GP. This study provides a new method of bamboo fiber preparation and the feasibility of applying it to reinforce GP.