| With the implementation of China's large-scale railway speed improvement and transformation, and a strong need for the development of high-speed passenger line, ballastless track began large applicated. But ordinary slab track also produced a number of difficult issues to overcome, such as great stiffness, too easy to crack, hard to maintance, one of them is a serious noise hazard. In a variety of railway noise, wheel/rail rolling noise, as the train speeds increase to become a major noise source. Currently measures in control of wheel-rail rolling noise mainly by improving and optimizing the rail structure to achieve, but rarely considered the impact of the foundation under rail. Asphalt concrete as a good material get a lot of applications in the highway, having the advantages of good elasticity, waterproof, easy to maintain that the cement concrete is not available. This thesis relying on the subject-the study of the embankment structure test for the full section of asphalt reinforced foundation of Chengdu-Dujiangyan inter-city rail, using Abaqus finite element software, establish the wheel/track noise model of three kinds of structures that is ACRS-1 type, ACRS-2 type and ordinary slab track. With the numerical simulation of the wheel/track noise of these structures, through calculation and comparison, this thesis analyses the noise level of different foundations under rail.The mian content and results of the study are as follows:(1) Established the wheel/rail rolling noise model with asphalt concrete foundation under track;(2) By calculating and comparative, analysed the noise reduction performance of asphalt concrete foundation under rail, the results showed that the noise of the ACRS-1 type is 2dB(A) lower than the ordinary slab track's.(3) Through the Parameter Sensitivity Analysis of the ACRS-1 type, found that the noise decreases with the increase of the thickness of asphalt layer, increases as the increase of the temperature of the asphalt layer, but this change is not obvious. |
