INTERNATIONAL CONGRESS ON RECENT ADVANCES IN SCIENCES AND TECHNOLOGY - Kuala Lumpur - Malaysia (2019-02-20)

Durability Characteristics of Geopolymer-based Materials Using Seawater and Water Glass Solution as Alkaline Activators
This paper illustrates a special investigation on geopolymer-based materials synthesized from fly ash (solid phase) in conditions of sodium silicate solution and seawater (liquid phases). The mixtures of geopolymer were designed with proportion changes of among materials to evaluate effects of the proportions to engineering properties of products. The specimens were molded into cubes with 50 mm of size, and then cured at room condition (28 oC, 80 % of humidity) for testing engineering properties for 28 days, 90 days, and 180 days. The engineering properties of geopolymer concrete samples included compressive strength (MPa), water absorption (kg/m3), and volumetric weight (kg/m3). Finally, the best specimens on engineering properties (the highest value of strength and low values of water absorption (kg/m3) were selected to characterize for microstructure using X ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). The results showed the fly ash-based geopolymer concrete using sodium silicate solution and seawater was very good performance with value of 180 day-compressive strength at 32 MPa, water absorption and volumetric weight were at 120 kg/m3 and 2150 kg/m3, respectively.
Dr. Hoc Thang Nguyen