基于索-梁组合结构的大跨斜拉桥BFRP拉索参数激励非线性振动机理研究

Applying Basalt Fiber Reinforced Polymer (BFRP) cables on long-span cable-stayed bridge can effectively improve the mechanical performance and economic performance of the long-span bridge, which will become a new type cable with good application prospect for the long-span cable-stayed bridge. However, BFRP cables are prone to large amplitude vibration induced by the parametric excitation under the actions of wind, rain and the traffic load due to their light quality, small stiffness and low internal damping, which seriously threatens the security and durability of the long-span cable-stayed bridge. Therefore, the effective measures should be taken to suppress this large vibration. However, the less research has been done, which refers to the large amplitude vibration of BFRP cables induced by the parametric excitation. Due to the unknown mechanism, the vibration control of the BFRP cables cannot be carried out. According to the problem of the unknown mechanism of the parametric vibration, this project will study the nonlinear vibration behavior induced by the parametric excitation, which take the BFRP cables as research object. Based on the cable-beam structure model, this project will adopt the method of the model vibration test, finite element analysis and mechanical modeling to carry out the study. Based on the model vibration test, the project will analyze the nonlinear vibration characteristics and determine the influence factors of the nonlinear vibration behavior of BFRP cables under the parameter excitation. Finally, the mechanical model with a high accuracy will be established. Based on the above studies, the nonlinear vibration mechanism of the BFRP cables under the parameter excitation will be developed. The study results will provide reference for vibration control of the BFRP cables on the long-span cable-stayed bridges, which have an important theoretical significance and application value of engineering.

玄武岩纤维增强复合材料(BFRP)拉索应用于大跨斜拉桥，能够有效地提升桥梁的力学性能与经济性能，是一种具有良好应用前景的新型桥梁拉索。但是由于其质量轻、刚度小、阻尼低，在风、雨及交通荷载的作用下，易发生由参数激励引起的大幅非线性振动，严重危害桥梁的安全性和耐久性，需要采取措施进行抑制。而目前关于BFRP拉索参数激励非线性振动的研究较少，其振动机理尚未明晰，导致拉索的振动控制无法有效开展。本项目针对BFRP拉索参数激励非线性振动机理不明的问题，基于索-梁组合结构模型，以BFRP拉索为研究对象，采用模型振动试验、有限元分析及力学建模的方法，对BFRP拉索的参数激励非线性振动行为进行研究，分析其非线性振动特性，确立其非线性振动的影响因素，建立求解精度较高的参数振动力学模型，揭示其参数激励非线性振动机理。项目研究成果能够为大跨斜拉桥BFRP拉索的振动控制提供依据，具有重要的理论意义和工程应用价值。

玄武岩纤维增强复合材料(BFRP)拉索应用于大跨斜拉桥，能够有效地提升桥梁的力学性能与经济性能，但是BFRP拉索质轻、阻尼低的特点，易产生参数激励作用下的大幅非线性振动，严重危害桥梁的安全性和耐久性。本项目基于索-梁组合结构模型，以大跨斜拉桥BFRP拉索为研究对象，通过动力学理论分析、有限元仿真模拟与模型振动试验，研究了大跨斜拉桥BFRP拉索参数激励的非线性振动机理。本项目主要完成了：①基于索-梁组合结构与相似准则，设计并开展了参数激励作用下大跨斜拉桥BFRP拉索的模型振动试验，阐明了参数激励作用下BFRP拉索的非线性振动规律。②利用BFRP拉索的模型振动试验设备，开展了参数激励BFRP索-梁组合结构的影响因素振动试验，揭示了参数激励作用下BFRP拉索非线性振动的关键影响因素及作用规律。③根据大跨斜拉桥BFRP拉索的构型，建立了BFRP索-梁组合结构的非线性振动力学模型，对参数激励作用下BFRP拉索的非线性振动进行了理论分析，并根据模型振动实验结果对该力学模型进行了修正，得到了高精度的参数振动力学模型；同时基于模型振动试验建立了BFRP索-梁组合结构的有限元仿真模型，并对比模型振动试验结果对有限元模型进行了修正，确立了能够有效模拟BFRP索-梁组合结构的仿真模型。本项目的研究成果为科学合理地进行大跨斜拉桥BFRP拉索的振动控制设计提供参考，有效地拓宽了高性能BFRP材料在桥梁工程中的应用，为后续的相关研究提供依据。基于本课题已发表论文14篇，其中SCI期刊论文8篇（中科院一区期刊论文3篇，二区期刊论文1篇，三区期刊论文4篇），中文核心期刊论文3篇，国际会议论文3篇，申请发明专利5项（全部受理进入实质审查程序），并参加国际会议2人次、国内会议3人次，培养硕士研究生6人。