| In recent years, the school bus traffic accidents frequentlyoccur in our country,which comes to the bad damage to the children’s occupant injury and social property damage.“School bus safety “has become the focus of the society.According to the incomplete statistics, from January in 2010 to the middle of December in 2011,there were 29 large school bus traffic safety accidents happened throughout the country.The total death were 108 and 358 light injured, involved 13 provinces.In addition, the extensively distributed and large base of the compulsory education of school-age children in our country and the implementation of the national rural elementary and middle schools mergepolicy, the potential of the domestic demand for the school bus has become a sharp growth trend.Therefore,the performance test and simulation research to the school bussafety,the finding to the potential safety problems and the analysis to the children’s school bus structure occupant injury situation are great practical significance to ensure the safety of life of the child occupant.The essay is based on the research status quo of the school bus at home and abroad,combined with the latest regulations of the school busissued in the country and by Hypermesh software to establish FEM of the safety test of the school bus to analyze the safetyof school body structure and to improve the research.Then, adding children occupants to build the simulated conditions, where the school bus is under the frontal and side-rolling crash’s safety test.Meanwhile, under the different belts constraints’ protection, the children’s dynamic response and injury are studied.This paper is to analyze and summarize the research results to provide the indicative data file to the school bus vendors and the research for the school bus& children’s injury.The study core could be concluded several aspects as below:1. This essay is based on a large number of related literature to introduce the safety performance test and the research and developmentsimulationof the school bus at home and abroad.then Summed up the domestic bus passive safety and simulation research is of great significance2.This essay involves the domestic bus regulations, the tools and theories of simulationand the theoretical foundation and damage parameters of the human body injury criteria and so on.3.Combined with the regulations---"The strength of student seat systems and their anchorages of special school bus”in my country to build the finite element modeling of the school bus seat, and than, in accordance with the regulations to verifide"“the backward of static load test ",and "the dynamic test".Through the comparison of the simulation and experimental results show that seat model available and effectively.4.Makers build FEM under the geometric frame structure of the bus body,according to the " Provisions of Strength for the Superstructure of Bus", bus makers set up relevant working conditions of the rollover test accordingly, and analyze collision energy absorption characteristics of the bus body structure. then verify the effectiveness of the model of car body.In addition to summarizes the results of rollover and find out the weak area of the bus and design flaws that appeared in front of body and side connections at the transition.To solve this problem add a different direction and forms the steel bracing strengthen optimization program at the beam waist up and down of the side body.After the rollover, the results reached rollover regulations,which also provide constructive suggestion school bus manufacturers to design and produce a safe and reliable school buses.5.We will put the verified school bus seat into the finite element model of school bus body frame, and build the simulation experiment condition of school bus roof pressure according to“The safety technique specifications of special school buses "requirement. By comparing the top pressure actual vehicle tests and finite element simulation test results of roof pressure, we validate effectively on the finite element model of the school bus-seat combination.The results showed that: Both coincide better, school bus body- Seat FEM effectively and available.6.In the effective body of school bus-seat model placed four fake passengers of Hybird III 6-year-old child in the seat model, research about sitting without a seat belt, two point seat belt or three-point seatbelt in frontal crash(collision speed of 20, 30 and 40 km/h) and rollover rolling condition and consider dynamics and damage parameters(head acceleration,the damage index HIC, head forward displacement, the chest synthetic acceleration) and so on with the regard to the characteristics of damage risk of injury and protection.The results showed that: the case that the 3-point seat belt protective properties is greater than the 2-point seat belt and the 2-point seat belt protective properties is greater than the 0-point seat belt.In the rollover conditions,the protection of the three-point seatbelt performance and injury risk associated with straps direction.Strap the same direction as the direction of the rollover, which protection performance is good, the opposite.Otherwise different。... |
