摘要随着国内运输市场的不断发展，半挂车架广泛应用于汽车运输行业，并成为行业的首选运输工具之一，需求量不断加大，对于安全性和经济性的要求更高，但传统的设计方法满足不了半挂车架的发展要求。传统的半挂车车架设计主要是利用安全系数法，通过计算应力变形小于最大许用量来进行设计，这种设计方法的优点是车架的安全性得到保障，但却忽略了车架的轻量化设计，使车架变得笨重。本文中介绍的是利用有限元法对车架进行设计，该方法在国内外广泛使用。通过有限元法设计车架的优点是车架在保证安全性的同时，能减轻车架的自重，达到轻量化设计的要求。
本文根据工作状态和受力特点，确定车架总的结构尺寸，选取合适的材料。通过弯曲用力确定纵梁的截面尺寸、横梁及其他结构件的尺寸，并对纵梁进行强度和刚度校核。32077
对车架纵梁进行有限元分析。首先通过Pro/E绘图软件绘制车架实体模型图，然后将模型导入workbench中进行分析。选取solid实体单元，材料Q235的基本属性是弹性模量 ，密度 ，泊松比 。通过车架整体结构默认划分网格；对于车架，主要对纵梁上翼面施加均匀载荷，对牵引板和中间车轴处施加约束条件。分析表明最大应力出现在工况1中的 ，出现在中间车轴处的连接横梁处，下于材料许用应力，满足要求；最大变形出现在工况2中，最大变形 ，满足设计要求。
车架的结构稳定性还受到路面情况的影响，当路面情况较差时，车架会产生振动而威胁车架安全。进行车架的模态分析，可以分析路面固有频率与车架的频率之间的关系，进而对车架进行改进。
在结构设计、有限元静力分析及模态分析的基础上，完成该型车架的装配图及零件图。
毕业论文关键词：半挂车架;有限元;模态分析
Semitrailer frame structure design and finite element analysis
Abstract
With the continuous development of the domestic transportation market, semi trailer frame is widely used in the industry of automobile and transportation industry, and become a preferred means of transport of, demand continued to increase, for safety and economic requirements higher, but the traditional design method can not meet the semi-trailer frame development requirements. Traditional semi trailer frame design is mainly by the safety coefficient method, the calculation should force deformation is smaller than the maximum allowable amount of the design, the advantages of this design method is guarantees security of the frame, but ignore the lightweight design of the frame, the frame becomes unwieldy. In this paper, the use of the finite element method for the design of the frame, the method is widely used in China and abroad. The advantages of the frame are the safety of the frame, and can lighten the weight of the frame, and meet the requirements of the lightweight design..
According to the working status and the characteristics of the load, the structure size of the frame is determined, and the appropriate material is selected.. By bending force to determine the size of beam section size, beams and other structural parts, and for longitudinal strength and rigidity check.
Finite element analysis of the frame beam. Firstly, the frame solid model chart is drawn by Pro/E drawing software, and then the model is imported into workbench for analysis.. The basic attribute of solid is the elastic modulus , density , Poisson's ratio of Q235 entity element . By default mesh frame structure; for the frame, mainly on the upper wing surface of the longitudinal beam applied uniform load and the traction plate and the middle axle position constraint conditions are imposed. Analysis shows that the maximum stress in condition 1, the intermediate axle connected with the cross beam at, than the material allowable stress, meet the requirements; maximum deformation in condition 2, maximum deformation meet the design requirements. 半挂汽车车架结构设计及有限元分析+CAD图纸:http://www.751com.cn/jixie/lunwen_28493.html