Compressive and splitting tensile strength of autoclaved aerated concrete (AAC) containing perlite aggregate and polypropylene fiber subjected to high temperatures
This paper presents the results of an experimental study on the residual compressive and splitting tensile strength of autoclaved aerated concrete (AAC) containing perlite and polypropylene (PP) fiber subjected to high temperatures. Cylinder specimens were subjected to various temperature ranges of 100, 200, 400, 800, and 1,000°C. The mixtures were prepared with AAC cementitious materials containing perlite at 15%, 20%, and 30% sand replacement. The polypropylene fiber content of 0, 0.5%, 1%, 1.5%, and 2% by volume was also added to the mixture. The results showed that the unheated compressive and splitting tensile strength of AACs containing PP fiber were not significantly higher than those containing no PP fiber. Furthermore, the presence of PP fiber was not more effective for residual compressive strength than splitting tensile strength. The 30% perlite replacement of sand gave the highest strength. Based on the results, it can be concluded that addition of PP fiber did not significantly promote the residual strength of AAC specimens subjected to high temperatures.
STUDY OF MECHANICAL PROPERTIES OF CONCRETE AT ELEVATED TEMPERATURES - A REVIEW
Concrete, the second highest consumed material afte r water in the world, plays a vital role in the con struction field because of the versatility in its use. Developments during the las t two decades have shown a marked increase in the n umber of structures involving the long time heating of concrete. In recognition of its importance, many researchers have attempted to investigate the effect of elevate d temperature on mechanical properties of concrete. These researchers, during t heir investigation, used materials with varying com bination and different experimental conditions. These materials include ce ment, different percentages of admixtures like fly ash, silica fume, metakaolin, finely grounded pumice(FGP), group granulated blast furnace slag(GGBS), polypropylene fibre(PP fibre), palm oil fuel ash(POFA), Portland pozzolana cement(PPC), rice husk ash(RHA), different fine and coarse aggregates, super plasti cisers, retarders and the conditions included a temperature range of 28 o C to 1200 o C . The other conditions that were varied are the s hapes and sizes of test specimens, curing methods, curing conditions and te st methods. The analysis of these investigations an d their results are reviewed and presented in this paper.
CNC Desktop Vertical Machining Bench Design and Cooling Fluid Application
Today's manufacturing technologies, the human work force is used and at least a minimum level of margin of error is used in CNC machines. Desktop CNC machine tools and CNC machine tools are developed in parallel with the development of personal computers. This study provides CNC training institutions for education, small and medium-sized enterprises for commercial purposes use the low-cost desktop machine has been designing and manufacturing of CNC vertical machining was carried out. Desktop CNC machine tools and production capacity to handle the kind of material was applied to increase the cooling fluid. Through A199 and Fe37 the cooling fluid application desktop CNC machine tools, such as processing of materials that are difficult to successfully processed. Keywords—CNC, Desktop CNC Machine, CNC Design