نوع مقاله : مقاله پژوهشی
1 استاد، دانشکدة مهندسیراهآهن، دانشگاه علم و صنعت ایران، تهران، ایران
2 دانش آموخته کارشناسیارشد، دانشکدة مهندسیراهآهن، دانشگاه علم و صنعت ایران، تهران، ایران
عنوان مقاله [English]
The use of steel fibre instead of Rebar reinforcement or in combination with them have advantage such as increasing flexibility, energy absorption and control of crack. Laboratory studies have been performed on the performance of slabs with steel fibres, but no specific numerical study has been performed that enters the fibre properties directly into the analysis process. Steel fibre concrete in this study modeled with finite element method and laboratory work with existing fibre-reinforced slab compare and validate. Then, with the development of fibre-reinforced slab track model, relies on the rebound under the bed moving a simulated load. The results show that the presence of fibres in the service load range has little effect on the shear and flexural forces of the slab.In the following, using FIB regulations, the process of designing steel fibre concretes and the possibility of using steel fibres in slab track is examined. The results show that the use of fibres in the slab alone does not have the necessary flexural strength to withstand the incoming loads and the crack width is obtained several times the allowable value of the regulations. As a result, the combination of fibres and reinforcement is used to control cracks and the design graph of the combination of fibres and reinforcement in the slab is obtained. The results show that with the addition of fibres, the amount of reinforcement required is slightly reduced and the crack width is significantly reduced. For example, in the case of axial load of 25 tons, load speed of 120 km / h and hardness of 32,000 kN/m with fibre volume percentages of 0.25, 0.5 and 0.75 in slab track model, the reinforcement used is reduced by 26, 30 and 35% respectively.as well as crack width used is reduced by 3.5, 4.9 and 6.3% respectively.