Glass Fibre Reinforced Concrete Use in Construction Eng
Glass-fibre reinforced concrete (GRC) is a material made of a cementatious matrix composed of cement, sand, water and admixtures, in which short length glass fibres are dispersed. It has been widely used in the construction industry for non-structural elements, like façade panels, piping and channels. GRC offers many advantages, such as being lightweight, fire resistance, good appearance and strength. In this study trial tests for concrete with glass fibre and without glass fibre are conducted to indicate the differences in compressive strength and flexural strength by using cubes of varying sizes. Various applications of GFRC shown in the study, the experimental test results, techno-economic comparison with other types, as well as the financial calculations presented, indicate the tremendous potential of GFRC as an alternative construction material.
The role of the interface in glass fibre reinforced cement
Abstract Glass fibre reinforced cement (GRC) provides an interesting example of interaction between a brittle fibre and a porous brittle matrix which is reactive towards the reinforcement. It is also a case in which the composite fails by multiple fracture. The durability of GRC produced from ordinary Portland cement and an alkali-resistant glass fibre recently developed in the U.K., has been studied over a period of three years under different environmental conditions by measuring the variations in the mechanical properties of these composites with age. The experimental results are interpreted in terms of the micromechanics of failure for these composites and an assessment is made of the role of the interface in controlling the behaviour of the composite at various stages of its life. It is concluded that the properties of the interface in GRC change with time, partly due to chemical attack on the fibre which weakens the reinforcement but also due to changes in the physical properties of the fibre bundle and porosity and volume changes in the matrix as it sets and hardens. It has, however, not yet been possible to characterise the materials nature of the interface in GRC composites.
Full-scale measurements of SO2 gas phase concentrations and slurry compositions in a wet flue gas desulphurisation spray absorber
Abstract Two measurement campaigns were carried out at ENERGI E2's Asnaes Power plant, unit 5. The unit has a capacity of 620 MW e and is equipped with a wet flue gas desulphurisation (FGD) plant employing a counter-current spray absorber with five spray levels. In the first campaign, the power plant was firing Orimulsion ® with 2.85 wt% S resulting in a flue gas concentration of SO 2 exceeding 2000 ppmv. In the second campaign, the fuel applied was a low-S blended coal and the SO 2 concentration in the raw gas was around 400 ppmv. A novel probe for in situ sampling of gas phase concentrations in wet FGD spray absorbers was developed and applied for measuring axial profiles of the SO 2 gas phase concentrations in the absorber. The expected decrease in SO 2 concentrations along the height of the absorber was found in the spray section (from height 26.5 to 36.2 m) whereas the SO 2 concentration above the holding tank and below the gas inlet was quite low probably due to long local residence times in the region. Horizontal variations, due to somewhat different flow conditions near the column wall were investigated and the SO 2 concentrations were found to be higher near the wall. Measurements at different gross loads showed that the SO 2 gas phase concentration at a given position inside the absorber was roughly linearly related to the L/G ratio in the measuring interval. Turning off one of the lower spray levels, while burning coal with low S content, did not lower the overall removal efficiency of the absorber. However, the SO 2 gas phase concentration inside the lower part of the absorber was increased by a factor of 2–3. Measurements of slurry pH at different positions showed a decrease of approximately 0.5 units from the upper to the lower part of the absorber. The full-scale measurements provide a detailed set of experimental data for validation of mathematical models of a wet FGD spray absorber.