Road traffic accidents involving coaches do not happen very often, but they are very dangerous because they affect a large number of passengers. Coaches (or intercity buses) are not equipped with safety belt harnesses. Valid regulations do not impose any obligation on coach manufacturers to provide intercity buses with either two- or three-point safety belts. This fact may result from the unawareness of risks and injuries that might befall the passengers with no safety belts during accidents. That is the reason why this work aims to compare the aftermath of coach accidents with no safety belts and the ones with safety belts. A detailed aim of this research is to analyse the results of dynamic loads during a frontal impact exerted on coach passengers travelling with and without (two- and three-point) safety belts. This objective was achieved by performing experimental studies and modelling which focused on the process of dynamic load transfer on the human body during a traffic accident. The research was conducted parallel on an adult and a child. The equivalent of a 50th percentile male was a hybrid III dummy (M50), whereas a child at the age of about 10 was represented by a P10 dummy. A numerical model was generated and verified in experimental testing in the scope of kinematics. Also, the comparison of the recorded courses of forces, acceleration, and moments was conducted. The results obtained from the tests were analyzed regarding the injury criteria for head, neck, and thorax. It was observed that both for the two-point safety system and the lack of safety belts, there were high values of acceleration recorded in the centre of gravity of the head. On the basis of the investigations conducted, it was ascertained that only a three-point safety belt system ensures the satisfaction of all injury criteria within admissible standards both in the case of criteria defined in the rules no. 80 and the rules no. 94 determined by the United Nations Economic Commission for Europe. It is the three-point safety belt system which should be obligatory in all intercity buses.

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正面碰撞时教练员乘客安全的实验和模型研究

涉及教练的道路交通事故并不经常发生，但是它们非常危险，因为它们影响了大量的乘客。教练（或城际公交车）未配备安全带线束。有效的法规不强加给大巴制造商任何义务为城际巴士提供两点或三点式安全带。此事实可能是由于在事故期间没有安全带的乘客可能会掉落的危险和伤害而没有意识到。这就是为什么这项工作旨在比较没有安全带的教练事故和有安全带的教练事故后果的原因。这项研究的详细目标是分析在有和没有（两点和三点）安全带行驶的长途旅客受到正面撞击时的动态载荷结果。通过进行实验研究和建模来实现此目标，该研究和建模的重点是交通事故期间人体上的动态载荷传递过程。这项研究是针对成年人和儿童同时进行的。相当于第50个百分位的男性是混合型III假人（M50），而约10岁的孩子则是P10假人。在运动学范围内，在实验测试中生成并验证了数值模型。另外，还比较了所记录的力，加速度和力矩的变化过程。分析从测试中获得的有关头部，颈部和胸部伤害标准的结果。观察到，对于两点式安全系统和缺少安全带，在头部的重心中都记录有较高的加速度值。根据所进行的调查，可以确定只有三点式安全带系统才能确保在规则No.2中定义的标准的情况下都满足可接受标准内的所有伤害标准。80号规则 94由联合国欧洲经济委员会决定。这是三点式安全带系统，在所有城际巴士中都必须使用。