Mechanism-based development and validation of a structural health monitoring for climate adaptive architectural Cottonid elements

棉纤维是一种可持续利用的纤维素基材料，由于化石资源的有限性，它在当今显示出新的应用潜力。由于其材料的粘性，Cottonid可用作可持续的，气候适应性的功能材料以及尺寸稳定的建筑材料。这些特性将该材料定义为用于生产传统结构应用以及创新仿生建筑的建筑元素的有效候选物。在联合项目的第一阶段，得出了单一制造和环境参数对棉纤维材料性能的基本关系。此外，优化了制造工艺，目的是增加材料的吸湿性。获得的结果允许建立一个基本的了解棉的相互作用与环境。关于Cottonid作为建筑元素的应用，在后续项目中，将探索在结构健康监测（SHM）材料中实施传感器和传感元件（组件）。Cottonid的制造原理是将单层纸层层叠加在一起，这对于SHM传感器的集成具有很大的潜力。关于集成例如用于温度和应变测量的光纤传感器（FBG）的一个基本问题是，它们是否通过保持其功能而经受住了羊皮纸化过程。应首先采用物理化学方法对此进行验证，然后在驱动和疲劳实验中根据材料厚度进行研究。在这里，还将考虑并进一步开发用于评估材料含水量的电阻测量。已建立的SHM方法将进一步与固有应变测量的创新方法进行对比，其中Cottonid试样将用压电氧化锌进行改性。同时，应分别通过长期实验推导和研究不同棉科变种的气候特异性应变谱。最后，对材料的生物降解行为进行了表征。第一阶段资金的优化制造工艺将在后续项目中得到进一步发展，以实现气候适应性建筑Cottonid元件的SHM传感器的应用。将通过分析研究以及驱动和疲劳实验来验证仪器化Cottonid元件的功能和性能，以获得有关材料行为和真实的天气条件下的长期行为的基本结果。通过实施SHM传感器和探索该领域的创新仿生方法，后续项目代表了Cottonid元素在建筑和土木工程中的预期应用。

Cottonid is a cellulose-based, sustainably available material, which exhibits new application potential nowadays due to the finite nature of fossil resources. As a function of its material tickness, Cottonid can be used as sustainable, climate adaptive functional material as well as dimensionally stable construction material. These properties define the material as an efficient candidate for the production of architectural elements for conventional structural applications as well as for innovative biomimetic architecture. In the first phase of the joint project, basic relationships between single manufacturing as well as environmental parameters on the material behavior of Cottonid were derived. Further, the manufacturing process was optimized with the aim to increase the hygroscopicity the material. Obtained results allowed to build up a basic understanding of Cottonid‘s interaction with its environment. With regard to the application of Cottonid as architectural element, in the follow-up project the implementation of sensors and sensory elements (assemblies) in the material for a structural health monitoring (SHM) will be explored. The manufacturing principle of Cottonid by layering single paper layers on top of each other has great potential for the integration of SHM sensors. One fundamental question concerning the integration of e.g. fiber optic sensors for temperature and strain measurements (FBG) is, if they withstand the parchmentizing process by maintaining their function. This shall be verified first with physicochemical methods and subsequently investigated in actuation and fatigue experiments as a function of the material thickness. Here, also electrical resistance measurement for assessment of materials‘ moisture content will be considered and further developed. Established SHM methods will further be contrasted with an innovative apporach for intrinsic strain measurement, where Cottonid specimens will be modified with piezoelectric zinc oxide. Accompanying, climate specific strain spectra of different Cottonid variants shall be derived and investigated via long-term experiments, repectively. Finally, the biological degradation behavior of the material is characterized. The optimized manufacturing process from funding phase 1 will be further developed in the follow-up project to realize an application-oriented implementation of SHM sensors for climate adaptive architectural Cottonid elements. Functionality and performance of the instrumented Cottonid elements will be verified via analytical investigations as well as actuation and fatigue experiments to derive essential findings concerning the material behavior and ist long-term behavior under real weather conditions. By the implementation of SHM sensors and the exploration of innovative biomimetic approaches in this field, the follow up project represents a brigde to the intended application of Cottonid elements in architecture and civil engineering.