Abstract: In order to avoid vehicle rear-end collision accidents, this paper analyzes the braking behavior characteristics of the vehicle group based on the roadside fixed collection tests. The results show that the reasons for the braking of the car group are the changes in the running state of the preceding vehicle and the prediction of the hazard of the vehicle. The main reasons for the braking of the first car in the car group are the lane change and the close distance of the following car. When the car group brakes, the first car mostly brakes slightly. the greater the braking deceleration of the preceding car, the more obvious the braking response of the driver of the following car. as the following distance and the time headway of the vehicles in the car group decrease, when the front brake light is on, the following car will output larger braking deceleration. the increase time of braking deceleration varies greatly depending on the driving style of the driver.

Key words: Expressway car group; Following behavior; Braking behavior; Braking deceleration

摘要： 为避免车辆连环追尾事故，文章基于路侧固定式采集试验，对车群制动行为特性进行 分析。结果表明，导致车群发生制动的原因有前方车辆运行状态变化和自车危险预测；车群 首车产生制动的主要原因有前车换道和跟车距离过近。车群制动时首车多为轻微制动，前车 制动减速度越大，后车驾驶人制动反应越明显。当前车制动灯点亮时，跟车距离和跟车时距 越小，后车的制动减速度越大。制动减速度增长时间因驾驶人驾驶风格的不同存有较大差异。

关键词: 高速公路车群；跟车行为；制动行为；制动减速度