Study On Road Oversize Cargo Transportation Turning Safely On Longitudinal Slope

Since the implementation of urban development planning strategy in the western region of China,the road transportation industry in the western region has developed rapidly and the freight volume is increasing day by day,among which the road freight volume accounts for more than 70% of the total freight volume.Bulk transport,as an important support for the national large-scale key engineering projects,plays an important role in road freight transport.Most of the western regions of China are mountainous landforms,and there are many longitudinal slope turning roads,which are more likely to occur in the transportation of large vehicles and goods.However,there are few studies on the longitudinal turning of large truck groups,so it is necessary to analyze the longitudinal turning of large truck groups to improve the transportation safety of large truck groups.In this paper,relevant literature at home and abroad is reviewed to study the current situation of longitudinal slope turning of large vehicle groups.The longitudinal slope turning is divided into three stages: straight uphill stage(ramp section),straight uphill stage into circular arc stage(curved slope section)and circular arc stage(curve section).The tractive force,strength,stiffness and stability of the fully mounted vehicle group in three stages are analyzed.Traction analysis includes three stages.Traction safety model is established under the critical condition that the traction force is greater than the driving resistance.Strength and stiffness analysis consists of three phase front axle load and bending moment and deformation analysis,to empty front axle allowed minimum load,full load when the front axle and rear axle to allow maximum load to critical conditions to establish load security model,with the goods two maximum bending moment and deformation of the fulcrum force under the action of bending moment and deformation is established with the critical conditions of security model;The stability analysis includes three-stage rollover stability analysis and sideslip stability analysis.The safety model of stability is established under the critical stability state that the vehicle group does not rollover on the ramp and bend,and no sideslip occurs on the slope,bend and bend.Then,ANSYS is used for modeling and simulation,Trucksim for stability analysis.and ANSYS is compared with the theoretical safety model to verify the correctness of the model.Finally,by using VS language and Access database,the safety system of longitudinal turning of highway bulk-transport is developed based on the theoretical models of traction,stiffness,strength and stability,and the safety of longitudinal turning of bulk-transport vehicles is obtained.