Showing papers on "Geopolymer published in 1996"

Fire response of geopolymer structural composites

Abstract: : The fire response of a potassium aluminosilicate matrix (geopolymer) carbon fiber composite was measured and the results compared to organic matrix composites being used for infrastructure and transportation applications. At irradiance levels of 50 kW/sq m, typical of the heat flux in a well developed fire, glass- or carbon-reinforced polyester, vinylester, epoxy, bismaleimde, cyanate ester, polyimide, phenolic, and engineering thermoplastic laminates ignited readily and released appreciable heat and smoke, while carbon-fiber reinforced geopolymer composites did not ignite, burn, or release any smoke even after extended heat flux exposure. The geopolymer matrix carbon fiber composite retains sixty-three percent of its original 245 MPa flexural strength after a simulated large fire exposure. (MM)

Mechanical properties and fire response of geopolymer structural composites

Abstract: One of the major concerns in using Fiber Reinforced Composites in applications that might be subjected to fire is their resistance to high temperature. Some of the fabrics used in FRC, such as carbon, are fire resistant. However, almost all the resins used cannot withstand temperatures higher than 200{degrees}C. This paper deals with the development and use of a potassium aluminosilicate (GEOPOLYNER) that is inorganic and can easily sustain more than 1000{degrees}. The results presented include the composite behavior in tension, flexure, and shear. Tests have been conducted on the virgin samples and samples exposed to temperatures from 200 to 1000{degrees}. The results indicate that the composite can withstand 327, 245, and 14 MPa in tension, flexure, and shear respectively. It retains about 63 percent of its original flexural Strength at 800{degrees}. The fire response of the carbon fiber composite was measured and the results compared to organic matrix composites being used for infrastructure and transportation applications. At irradiance levels of 50 kW/m{sup 2} typical of the heat flux in a well developed fire, glass- or carbon-reinforced polyester, vinylester, epoxy, bismaleimde cyanate ester, polyimide, phenolic, and engineered thermoplastic laminates ignited readily and released appreciable heat and smoke, while carbon-fiber reinforcedmore » GEOPOLYNER composites did not ignite, bum, or release any smoke even after extended heat flux exposure.« less

Solidification and materialization of fly ash powder with geopolymer

Abstract: PURPOSE: To effectively utilize the fly ash of industrial waste to produce a material high in surface hardness and strengths by solidifying a sodium silicate aqueous solution and fly ash as raw materials at the ordinary temperature or under a steam-ageing condition. CONSTITUTION: For example, 33.3 pts.wt. of a sodium silicate aqueous solution having a density of 1.278g/cm and 66.7 pts.wt. of fly ash having a density of 2.28g/cm and a specific surface area of 4050cm /g are mixed, aged at room temperature for 28 days and in the presence of steam at 60 deg.C for a day, immersed in water for three days for the removal of unstable components, and further aged at room temperature under a natural drying condition for seven days to obtain a specimen, which has a flexural strength and a compression strength that are expressed in the table.

Solidification and materialization of kaolin powder with geopolymer

Abstract: PURPOSE: To simplify the production method by solidifying a sodium silicate aqueous solution and kaolin powder as raw materials at the ordinary temperature or in a steam-ageing state without calcining the kaolin powder. CONSTITUTION: For example, a sodium silicate aqueous solution in an amount of 42.9 pts.wt. kaolin powder in an amount of 51.4 pts.wt., potassium silicofluoride or blast-furnace water-granulated slag as a reaction accelerator in an amount of 5.7 pts.wt. based on the whole weight of the mixture are mixed, aged and solidified in air at room temperature for 28 days, and subsequently immersed in water for three days to obtain a specimen (A) from which unstable components are removed. Further, the specimen A is dried at room temperature for seven days to obtain a specimen (B). The specimen A has a flexural strength of 2.1-4.1MPa and a compression strength of 3.4-7.2MPa, and the specimen B has a flexural strength of 2.6-22.4MPa and a compression strength of 5.2-34.3MPa.