拖拉机安全驾驶室强度非线性有限元分析

为了避免由于拖拉机翻车事故引起的人员伤亡，提高拖拉机工作时的安全性，设计安全可靠的大中马力拖拉机驾驶室，并且使之能通过OECD标准，以某型号拖拉机驾驶室为研究对象，建立了该安全驾驶室的精确三维模型，并采用非线性有限元方法，按照OECD标准规定的要求，对模型进行了加载分析。驾驶室被简化成梁和板单元，采用弹簧单元模拟驾驶室与机身前支架之间的橡胶减震垫。计算结果表明：拖拉机驾驶室在按照试验要求模拟加载完成后，驾驶室变形吸收能量达到OECD标准规定的要求时，驾驶室部分粱和底板的应力已经达到屈服应力，进入了塑性变形，但变形后的驾驶室没有侵入安全容身区。后推、后压、侧推、前压和前推试验中驾驶室的最大变形分别为111、4、168、19和 47 mm，变形最大发生在力的作用位置处。该方法为设计能通过OECD标准试验的拖拉机安全驾驶室提供了一定的参考依据。

Nonlinear finite element analysis of strength of tractor safety cab

In order to reduce fatal work-related injuries caused by tractor roll over accidents, fixing safety cabs on tractors was proved to be the best choice. A kind of large horsepower tractor safety cab integrated with roll over protective structure (ROPS) was designed. The exact three-dimensional model of the tractor cab was established, and the strength of the cab was analyzed by using non-linear finite element method. The test was simulated according to OECD codes. The cab was simulated by using beam and shell element. Rubber anti-vibration mountings fixed between the cab and front bracket of the tractor were simulated by spring element. The analysis results showed that, at end of the simulation test when the energy absorption met the requirement of the OECD codes, the maximum stress in some parts of the cab reached yield stress and appeared plastic deformation. However, the clearance zone was not infringed. During the first and second longitudinal loading test, the maximum deformation was 111 mm and 47 mm, respectively. In loading from the side test the maximum deformation of 168 mm was found. In the first and second crushing tests, the maximum deformation was 4 mm and 19 mm, respectively. The maximum deformation happened in the place where the loads were applied. Therefore, the analysis results provided a basis for designing tractor cab with ROPS which could pass the homologation tests established in OECD code 4.