洪水作用下车辆稳定性试验与安全标准研究

对洪水作用下车辆失稳时的受力情况进行分析,推导出车辆失稳临界条件方程,并结合三款不同型号1:18的车辆模型渡槽试验,确定方程中拖曳力系数、摩擦力系数、淹没深度与排开水质量关系。根据流动相似原理计算原型车辆失稳的临界水深-流速关系,并以此提出了车辆部分淹没时“大中小”车型的多层次安全标准。研究结果表明：随着水流流速增大,失稳临界水深变小,且流速-水深曲线“凹凸性”发生变化；随着车辆部分淹没水深增加,不同来流情况的临界流速逐渐趋近；同款车型在相同的水深条件下,侧向来流比正向来流更容易失稳；三车并列时稳定性介于侧向来流和正向来流之间；路面坡度越大,车辆越容易失稳；质量越大车辆,稳定性越好。

Experiment and Safety Criteria Analysis of Vehicles Stability under Flood

The force state of the vehicles under submerged condition is analyzed. According to the equilibrium slip theory, the critical force condition equation of vehicle instability is deduced. Then three different kinds of models in 1:18 scale in flume experiment is conducted, which confirms the drag force coefficient, friction coefficient and the relationship between submerged depth and drain water quality of different vehicles in the critical force condition equation. Finally, the multi-level safety standard of the vehicles under the flooding is put forward. The results show that: (1) the critical water depth decreases with the increase of the flow velocity ; With the increase of the submerged depth of the vehicle, the critical flow velocity of different flow conditions is approaching; (2)comparing with the positive flow, the lateral flow is easier Instability in the same depth of water condition; the stability of three cars parallel parking is between the lateral flow and the positive flow; (3) the greater the slope of the road, the more easily the vehicle instability;(4) the greater the quality of the vehicle, the better stability.