| With the wildly development of high-speed railway, passenger railway line, the subway,and modern trams, the usage of ballastless track technique in track structure is also increased,but the problem of the track plate cracking is also appeared. The current track plate fracture repairing techniques are all passive techniques which can not solve the problem of the crack appearing thoroughly.Combined with pre-stressed Carbon Fiber Reinforced Plastic strengthening technology of the bridge, analyzed from four aspects, strength of materials, construction plan,applicability of construction and the late maintenance, determined that the pre-stressed CFRP strengthening technology can be used to track slab reinforcement. Summarized the existing tension characteristics of the equipment by studying the existing tensioning device. Showed the sketch of tensioning device which can be applied to the track plate structure reinforcement by combining with the actual requirement of existing lines construction. Measured the debonding bearing capacity of the carbon fiber cloth reinforced concrete interface by the carbon fiber cloth and concrete bonding performance experiment.According to the relevant specification, deduced the formula for the bearing capacity of track plate’s normal section of pre-stressed CFRP and according to the formula, wrote an available program which can be used to guide the pre-stressing of carbon fiber cloth during construction. Set up two kinds of reinforcement model by ANSYS, and by comparing with the different reinforcement effect, found that it is much easier to make the concrete get bigger tensile stress by the way of sticking between the two sleepers, so decided to reinforce on the both side of sleeper as the way of reinforcement. Set up four groups of model which is based on principles of control variables, respectively compare the effects of with or without reinforcement, the initial pre-stressing, the thickness of CFRP. The analysis shows that the cracking moment of reinforced track slab is greatly improved.Set up the fracture mechanics model by Workbench, surface elliptical crack model is used as crack model. Compare the effect of with and without reinforcement and the size of the initial pre-stressing. Proved that the elastic-plastic fracture model will get larger discreteness which is calculated by K integral. After calculating the J integral, contrast the J integral values of the crack front in each group, found that after strengthening the track plate,the main development direction of crack will change. With the increase of initial pre-stressing,the influence to the crack tip is almost not changed. |
