空间网架结构在设备激励下的损伤识别失效机理与修复策略的研究

There are many suspension devices and moving loads in space truss structures such as cement clinker silo, preliminary homogenization library and aviation maintenance hangar. Some local bolts of the space truss structures can loose and some members can bend or even crack under long term equipment loads and the overall structure failure caused by accumulation of the damage occurs frequently. There project consists of three parts. Firstly, dynamic characteristics and dynamic response of space truss structures under random excitation could be obtained through the method of dynamic test and health monitoring, so the damage detection theory caused by random excitation of the existing space truss structures will be established. Secondly, lose efficacy mechanism for overall structure caused by local damage will be analyzed deeply and failure path of the structure can be predicted, which will provide an early warning for the safe running of the structure. Thirdly, repair equipment and repair methods for local damage of the structure based on the experiment could be developed under the condition of safe equipment running and minimum cost. Combined with the dynamic detection technology and damage identification theory, this research emphasizes lose efficacy mechanism of complicated structure and repair of local damage and will be of great practical value to the safe running and disaster prevention and reduction of the existing large scale space structures.

在水泥行业熟料库、预均化库和航空业维修机库等空间网架结构中，存在大量的悬挂设备和移动荷载，这些设备的长期运行会造成网架结构局部的螺栓松动和杆件弯曲及断裂等结构损伤，损伤积累所导致的结构整体失效屡有发生。本项目的研究分三方面：首先，通过动力检测和健康监测方法获得设备随机激励下网架结构的动力特性和动力响应，建立起在役空间网架结构设备随机激励所导致的损伤识别理论。其次，对于网架结构局部损伤所导致的整体失效机理进行深入的分析，预知结构整体失效的开展路径，为保证结构的安全运行提供预警。然后，通过实验研究在保证结构安全运行和降低修复造价的前提下，开发一种适合网架结构局部损伤修复的实用修复设备和修复方法。本项目的研究涵盖动力检测和损伤识别理论，同时将复杂网架结构的失效机理和局部损伤修复作为研究重点内容，对保证在役大型空间结构安全运行和防灾减灾具有重要的应用价值。

在国家自然科学基金面上项目支持之下，主要科研工作和研究成果涵盖如下几项：（1）首先进行了网架杆件屈曲后性能的实验和理论分析，获得了精确的弹塑性屈曲后模型，该模型考虑了端部锥头、套筒和螺栓的组合效应。（2）对网架结构在移动悬挂荷载作用下进行模拟实验和理论分析，提出了设备激励下的网架结构的损伤识别方法，研制了相应的损伤识别预警机制。（3）对现有损伤识别方法进行了深入的研究和剖析，明确了其适用范围。（4）针对不同意外荷载作用下网架的垮塌行为进行模拟分析，明确了关键部位的损伤演化规律和结构的失效机理，进而提出了针对关键部位的加固策略。（5）考虑到网架结构杆件众多，将人工智能方法引入损伤识别，在传感器的优化布置方面获得了应用。（6）对网架结构风致作用和风振效应进行了初步研究，开发了基于FLUENT软件的网架结构风压和风振分析计算软件，对风荷载作用下的网架结构抗垮塌设计提供可靠的数值模拟依据。上述工作有些已经申请了相关专利，并获得了授权，有些则申请了相关的软件著作权。