Strength Analysis And Crashworthiness Research Of Double-decker Coach Body Structure Frontal Impact

With the sustained and rapid development of society economy and improvement of road conditions, retain number of buses increases sharply, and the passenger buses running on highway have developed towards large-scale and high-speed. To ensure driving safely, a large quantity of active and passive safety devices are widely used on coaches, which greatly improve bus safety than before. However, extra serious traffic accident caused in collision and rolling accidents still account for a large proportion each year, which bring about enormous losses to the national economy and people's lives. So, the automotive crash safety has become one of the main research topics in auto industry, and also got high priority by government, business and popular. Double-decker coach is a new model invested to adapt to the development of highway coach industry in recent years, whose carrying capacity is 1.5 to 2 times of the ordinary type. Once accidents occurred, the casualties and property loss will be great. Therefore, the crash safety of double-decker coach has been attracted extensive attention.At present, the major automotive-producing countries in the world have established strict regulations to crash safety, which the exploitation and production of motor vehicles must follow rigidly. Along with the constant norms of the passenger car market in our country, the bus safety has been greatly improved, and safety regulations obtained important development. Though lots of related research domestic and abroad have been carried out, no safety regulations on market access was laid down as yet, which result in the lack of evaluation index of bus frontal impact safety.In this paper, based on the study of our country's traffic safety in recent years, according to the test requirements of frontal impact regulations ECE/R94 and GB11551-2003, using FEA procedure LS-DYNA, we study a 6140 double-decker coach deformation characteristics and crash safety in frontal impact through finite element analysis method for the first time. To get more objective and accurate evaluation of the double-decker coach frontal crash safety, we also put the test dummies and the occupant restraint device into the coach's frontal impact safety evaluation. Meanwhile, referring to the simulation results, we optimized the body structure, and increased the compression buffer absorption device, then do the simulation analysis of the improved body structure again. The results show that, the 6140 double-decker coach has a poor frontal impact safety, and large deformation exists in the front body structure, which caused that the driver and front passengers were acute shortage of residual space, seriously threaten the passengers' lives. The improved project mentioned in this paper can effectively enhance the crashworthiness of this double-decker coach, and also provides the effective way to improve the bus' frontal impact safety. Furthermore, the research in this paper can provide reference to the formulation of regulations to bus crash safety.