Study On The Barrier Of Equivalent Safety Degree In Mountainous Areas Of Highway

Roadside barrier as a kind of safety protection facilities to prevent the vehicle off the road,to reduce traffic accidents and protect the vehicle and personal safety plays a vital role.However,due to the mountainous area highway steep bend anxious,often lead to some vehicle speed too fast,or crashed across the roadside guardrail,traffic accident;in addition,the mountainous area highway around the terrain is very complex,the vehicle off the road,will be directly facing the complex road environment,easily lead to two accidents,so as to further increase the severity the traffic accident.Therefore,the roadside guardrail protection based on the effect of roadside environment on the traffic safety into consideration,put forward the concept of equivalent safety,used to describe the side of the road safety situation.The main work and research results are as follows:(1)First,combined with our country mountainous area highway roadside environment and traffic accident occurred in the roadside survey results,the main factors affecting the roadside will be divided into barrier,slope gradient and slope height,obstacle,roadside ditches,roadside water,and other factors in several aspects,and according to their characteristics analysis of the influence of the safety.(2)Combined with the characteristics of Chinese style highway roadside barrier,the roadside fence is divided into special barrier section and conventional barrier section.According to the special section of the roadside guardrail –the transition of guardrail and guardrail terminal,comparative experiments using the simulation software Hyper Works to simulate the vehicle collision with guardrail transition section and guardrail terminal,the experimental results show that the commonly used two lap type guardrail transition section did not reach a level of protection,two kinds of continuous transition can be achieved grade A and SB protection grade;round head type guardrail terminal and earth anchored end did not reach the standard of safety performance,the roll end can reach the standard.(3)According to the conventional section of roadside guardrail,using the theory of impact force to research,it was found that the use of B grade and above barrier can effectively resist the default under the condition of small passenger car;use the SB grade and above barrier can effectively resist the bus preset conditions;use the SA grade and above the preset conditions protective guardrail truck.Secondly,using the principle of function,the paper analyzes the concrete guardrail of the conventional barrier to resist the large capacity of the vehicle,and finally gets the minimum design height.(4)According to the actual road traffic accidents,analysis various factors associated with the level of roadside,and get the weight of their share in roadside traffic accident.Then through the analysis of roadside accident casualty data comparison and collision severity index ASI,combined with the research results of barrier protection ability,get the impact of various factors to quantify the numerical.According to the relationship between the factors,the establishment of the equivalent safety degree of the calculation model and evaluation criteria.