为了研究不同平纵线形指标条件下的互通式立交出口匝道分流鼻端行车安全性，采用小客车行车动力学仿真的方法，建立人、车、路仿真模型。通过改变分流鼻端的圆曲线半径、纵坡坡度，模拟不同条件下的行驶工况，分别对分流鼻端进行了平面线形和纵断面线形进行研究，得出不同工况条件下的车辆侧向加速度的响应输出，分析不同线形指标参数对分流鼻端行车安全的影响。研究结果表明：在匝道出口分流鼻端处，长缓和曲线+小半径圆曲线线形组合安全性优于短缓和曲线+大半径圆曲线线形组合。当主线设计速度为120km/h，纵坡为-5%时，车辆的侧向加速度最大值为0.58g，此时车辆侧滑危险性较大，建议设计中分流鼻端纵坡小于等于4%。为了保障分流鼻端行车安全，主线设计速度为120km/h时，分流鼻端圆曲线半径为350m，则纵坡应小于-3.5%；当圆曲线半径为300m，则纵坡应小于-3%。主线设计速度为100km/h时，分流鼻端圆曲线半径为300m，则纵坡应小于-4%；圆曲线半径为250m，则纵坡应小于-3.5%。

In order to study the safety of diverting ramp shunting nose end of interconnected interchange under the conditions of different vertical and longitudinal lines. The dynamic simulation analysis of the passenger car is carried out. The vehicle model, the road model and the driver's preview trajectory model are established. By changing the radius of the circular curve and the longitudinal gradient of the diverting nose, simulating the driving conditions under different conditions, the horizontal alignment and longitudinal profile of the diverting nose were studied respectively. The response output of the lateral acceleration of vehicles under different working conditions is obtained, and the influence of different linear parameters on the safety of the diverting nose end is analyzed. The research results show that: at ramp outlet, the safety of long transition curve with small radius circular curve combination is superior to that of short transition curve with large radius circular curve combination. When the design speed of the main line is 120km/h and the longitudinal slope is -5%, the maximum lateral acceleration of the vehicle is 0.58g, and the vehicle sideslip is more dangerous at this time. It is suggested that the longitudinal slope of the diverted nose is less than 4% in the design. In order to ensure the safety of the shunting nose end, when the design speed of the main line is 120km/h, the radius of the circular curved nose round curve is 350m, and the longitudinal slope should be less than -3.5%. And the radius of the circular curve is 300m, and the longitudinal slope should be less than -3%. When the design speed of the main line is 100km/h, the radius of the circular curved nose round curve is 300m, the longitudinal slope should be less than -4%, and the radius of the circular curve is 250m, then the longitudinal slope should be less than -3.5%.