变幅值多轴载荷工况下橡胶隔振器疲劳特性的试验与建模方法研究

Rubber isolators are widely used in many areas, such as automotive industries, national defenses, bridges and constructions, because of their large reversible elastic deformation, waterproof and airproof, and wearable. Usually, rubber isolators are used under a preload and excited with variable amplitude and multiaxial loads. To experiment and to model the fatigue characteristics of a rubber isolator is a complex research work for testing and modeling sophisticate rubber components under large deformation and with complex excitations...This project will research on experiment method and carry out experiments on rubber materials used for rubber isolators under variable amplitude and multiaxial (biaxial or triaxial) loads. To test and to model the fatigue characteristics for some commonly used rubber isolators and hydraulically damped rubber isolator in automotive industries under the complex loads, the following steps are to be carried out.Firstly, to obtain the stress or strain parameters of ruber materaials , the dynamic finite element analysis (FEA) of rubber isolator will be carried out by superimposing three constitutive models (hyper-elastic model, viscoelastic model and elasto-plastic model) to characterize the rubber materials,or fluid-structure interaction FEA will be done for hydraulically damped rubber isolators. Secondly, the damage parameter used for estimating the fatigue life is established, and it is the stress-based or strain-based parameters or the combination of stress and strain calculated with FEA. Thirdly, the cyclic counting method will be presented if the rubber isolators are used under variable amplitude and multiaxial loads. ..The objective of this research is : (1) to establish the fatigue database for rubber materials used commonly for automotive rubber isolators; (2) to establish the experiment method for measuring the fatigue life of rubber isolators under variable amplitude and multiaxial loads; (3) to model the fatigue performances for predicting the fatigue life of rubber isolators and hydraulically damped rubber isolators; (4)to enhance the fatigue life of rubber isolators for using the above experiment and modeling methods.

橡胶隔振器因其具有很强的弹性和良好的可塑性、隔水隔气、抗拉和耐磨等特点，广泛应用于汽车工业、国防、桥梁、建筑等领域。橡胶隔振器常在一定的预载和在变幅值、多轴载荷工况下的工作。对橡胶隔振器疲劳的试验和建模分析是一种变幅值、多轴复杂载荷工况下，由大变形、非线性材料组成的复杂橡胶结构部件疲劳试验与建模研究。.项目将开展常用于汽车橡胶隔振器配方的橡胶材料在变幅值、多轴复杂疲劳工况下的疲劳特性的试验研究。建立常用类型的橡胶隔振器和液阻型橡胶隔振器在复杂载荷工况下疲劳寿命特性的分析模型：用于疲劳寿命的分析参量是基于超弹性、粘弹性和弹塑性本构模型叠加得到的橡胶力学性能参量，或者是一些参量的组合；建立适用于变幅值、多轴复杂载荷工况的载荷循环计数法。项目以完善和发展橡胶材料疲劳性能数据库，建立提高橡胶隔振器疲劳特性的试验和建模方法，提高橡胶隔振器和液阻型橡胶隔振器疲劳特性为最终目标。

项目背景：橡胶隔振器因其具有很强的弹性和良好的可塑性、隔水隔气、抗拉和耐磨等特点，广泛应用于汽车工业、国防、桥梁、建筑等领域。橡胶隔振器常在一定的预载和变幅值、多轴载荷工况下工作。对橡胶隔振器疲劳的试验和建模分析是一种变幅值、多轴复杂载荷工况下，由大变形、非线性材料组成的复杂橡胶结构部件疲劳试验与建模研究。..主要研究内容：项目开展了汽车橡胶隔振器不同配方的橡胶材料在变幅值、多轴复杂疲劳工况下疲劳特性的试验研究。建立了常用类型的橡胶隔振器和液阻型橡胶隔振器在复杂载荷工况下疲劳寿命特性的分析模型；建立了适用于变幅值、多轴复杂载荷工况的载荷循环计数法。..重要研究成果：基于变幅载荷隔振器橡胶材料的裂纹扩展试验及建模方法，建立了15种材料的橡胶裂纹扩展模型，建立了变幅载荷下填充型天然橡胶疲劳试验与预测方法研究，提出了不同损伤参量对橡胶隔振器疲劳寿命预测结果的影响，对汽车动力总成橡胶悬置的疲劳寿命进行了实测与预测，证明了建立模型的正确性。..关键数据：发表论文：30篇， 其中SCI收录12篇， EI收录18篇。培养博士生：3名；硕士生6名，年轻教师1名。..科学意义： 项目建立了常用橡胶材料疲劳性能数据库，对由粘弹性、超弹性材料组成的隔振器的疲劳分析建立了理论分析的方法。