高速公路弯道路段载重汽车侧滑仿真及安全行车速度

Sideslip simulation and safe driving speed of truck on highway curve section

为了揭示高速公路载重汽车侧滑事故发生机理,分析侧滑时驾驶输入-道路-车辆的响应状态,寻找弯道路段载重汽车侧滑安全临界。针对侧滑事故研究受到真实试验无法开展的制约,采用ADAMS仿真软件,依据高速公路弯道路段载重汽车平衡条件,建立考虑刚柔耦合效应的载重汽车整车模型。分别采用3D样条路面和闭环控制方式建立非实测弯道路面模型和驾驶人模型,构建侧滑事故发生时驾驶人-道路-车辆瞬态动力学响应模型,并采用转向盘转角阶跃输入下的转向瞬态响应来评价载重汽车的操纵稳定性,实现仿真模型的可行性验证。参照实际采用参数值,对比设置道路条件、车辆条件、制动减速度、非实测路段特征点等ADAMS侧滑仿真工况。按照等差异划分,开展包含400、500、600、700、800、1 000、1 500、2 500 m共8种弯道半径,2%、3%、4%、5%、6%、7%、8%、10%共8种超高,0.2、0.4、0.6共3种路面附着系数的多组正交侧滑仿真试验,揭示载重汽车以不同速度在不同半径、不同附着系数的弯道路段下的侧滑轨迹变化规律,结合行车轨迹侧向偏移分析弯道特征点处的临界侧滑安全行车速度。结果表明:不同试验条件下高速公路弯道路段载重汽车轨迹侧向偏移量差异明显,最大可达2.456m,最小为0.053m,不同半径、不同附着系数下的弯道路段载重汽车瞬时转向临界侧滑安全行车速度阈值区间为47~97km/h。

To reveal the mechanism of sideslip accident of highway truck, the response state of driving input-road-vehicle in the case of sideslip was analyzed to find the truck sideslip safety criticality on curve section. As the data limit brought by the difficulties in field experiment, the whole truck model considering rigid flexible coupling effect was built by ADAMS according to truck＇s balance condition on highway curve section. The non-measured curve pavement model and driver model were built based on 3D spline pavement and closed-loop control, then the driver- road-vehicle transient dynamic response model was established when sideslip happened. Also, the steering transient response under step input of steering wheel angle was used to evaluate the operation stability of truck, which verified the feasibility of simulation model. Referring to the actual value, the ADAMS sideslip simulation conditions were set up, such as road condition, vehicle condition, braking deceleration, and characteristic points of non-measured section, etc. According to the equal difference, a series of orthogonal sideslip simulation tests on 8 kinds of turning radius （400, 500, 600, 700, 800, 1 000, 1 500, 2 500 m）, 8 kinds of super elevation （2%, 3%, 4%, 5%, 6%, 7%, 8%, 10%） and 3 kinds of pavement adhesion coefficients （0.2, 0.4, 0.6） were carried out, the simulation results revealed the sideslip trajectory change law of truck with different speeds and under different radii and different adhesion coefficients. Critical sideslip safe driving speed of characteristic points on curve section was obtained based on driving trajectory lateral offset. The results show that the truck driving trajectory lateral offset on highway curve section differs from each other obviously under different test conditions. The maximum is 2. 456 m, and the minimum is 0. 053 m. And critical sideslip safe driving speed of truck instant turning threshold on curve road section under different turning radius and pavement adhesion coefficients is between 47 to 97 km/h. 4 tabs, 7 figs, 18 refs.