Experimental and Analytical Investigations of Innovative Composite Materials Using GFRP and Iron Slag for Railway Sleepers

This paper presents further results of experimental testing and analytical investigation on the mechanical properties of fiber composite sleeper in order to evaluate its strength and behavior. Recycled high density polyethylene, iron slag, calcium carbonate, styrene and polyester resin were used with different percentages for manufacturing the proposed composite sleepers. Adding glass fiber ropes and woven laminates as a reinforcement to enhance the flexural capacity of the proposed composite material. Negative bending at center and positive rail seat compression were performed on full scale sleeper. Two full scale sleepers were proof loaded up to 72, 82 KN under negative bending test without any generated cracks. Also, under positive rail seat compression test, first crack occurred at load ranged from 170, 195 KN and failure load happened at load 270, 250 KN. That's mean that the strength of sleeper ranged from 36.39 to 39.30 MPa. This result showed that the proposed composite material of sleeper has sufficient strength to hold mechanical connections. Nonlinear finite element analysis (NLFEA) predicted the behavior up to failure load of the proposed composite sleeper reasonably well. This confirms that the behavior and failure modes of composite sleeper can be well predicted by simplified analysis procedures. Comparison of proposed composite with commercially available composite and timber sleepers' behavior was presented. It is found that proposed composite sleeper performance is near or similar to that of timber and better than that of commercially available composite sleepers. It is concluded that the proposed composite sleeper can be effectively used for timber sleeper replacement.