为了研究踏面凹形磨耗车轮的动力学行为，改进Kik-Piotrowski方法提出一种可考虑轮对摇头和轮轨多点接触的非Hertz接触模型，结合车辆-轨道耦合动力学理论计算具有实测踏面凹形磨耗车轮的CRH2高速动车组在钢轨上运行时的轮轨动态相互作用行为。计算结果表明，改进的Kik-Piotrowski方法可以很好地模拟磨耗车轮与钢轨的多点接触和非Hertz接触行为，轮轨法向力、轮轨蠕滑力以及接触斑形状都与CONTACT计算结果比较接近。对于踏面凹形磨耗的车轮，接触区域分布在车轮磨耗边缘的两个孤立位置，当接触斑从一个区域向另一区域转换时存在瞬时的两点接触。由于两点接触的过渡，接触区域在两个位置转换时造成的冲击效应并不明显。与无磨耗车轮的动力学响应对比，该类车轮踏面凹形磨耗对轮轨力的影响从总体上来说不大，对轮轨横向力的影响略大于对轮轨垂向力的影响，磨耗会增加轮轨垂向力和轮轨横向力的高频成分。
A modified Kik-Piotrowski method which is able to consider the yaw angle of the wheelset and multi-point contact is established in order to study the dynamic behavior of the vehicle with tread worn-wheel. Combining the vehicle-track coupled dynamics, wheel-rail dynamic interaction is investigated for the CRH2 EMU with tread hollow-worn wheel running on the straight line. Results show that the modified Kik-Piotrowski method can be used to accurately simulate the multi-point and non-Hertzian contact between worn wheel and rail; both the predicted wheel-rail contact patch and the wheel-rail contact force have good agreements with CONTACT. The contact patch is distributed in two discontinuous areas at the boundary of the main wear region of the wheel tread, and instantaneous two-point wheel-rail contact occurs when the contact patch switches from one area to another area. The impact effect induced by the variation of wheel-rail contact point is not significant due to the transition of the two-point wheel-rail contact. Compared with the dynamic response of the vehicle without worn-wheel, the wheel-rail forces are slightly affected by the tread hollow-worn wheel, the effect on the wheel-rail lateral force is more significant than that on the wheel-rail vertical force. Both the wheel-rail vertical force and the wheel-rail lateral force are increased to a certain extent at the high frequencies.
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