A Bio-Inspired Strategy for In-Plane Energy Dissipation through Suture Interfaces

该研究将探索一种新的策略，用于在板和壳的各个部分之间建立机械连接。这种方法的灵感来自于天然材料中的发现，其中各个部分经常被发现相互连接在拼图般的结构中。一个这样的例子是一些植物的种皮，其由刚性的、名义上平面的构建块组成，这些构建块通过柔性之字形接缝彼此连接。这些接缝称为缝合界面。本研究将重点关注缝合界面网络如何有助于韧性、损伤容限和构件之间的载荷传递效率。将对3D打印板壳系统进行工程分析、计算机模拟和实验。从这项研究中获得的知识将为设计新的轻质和损伤容限材料系统提供指导方针，这些材料系统在航空航天，海军，建筑结构，地面车辆和装甲中具有广泛的工程应用。研究的跨学科性质将涉及多元化的参与者，并将使学生接触到力学，材料，生物学和制造领域。该研究将采用综合分析，计算和实验方法，系统地量化生物启发拼图复合材料板和壳的机械形态效应。将采用混合分析和有限元建模方法来预测缝合界面和拼图复合材料的力学行为，包括混合模式损伤的产生和演变、缝合界面的两种基本失效机制以及失效机制的转变。3D多材料打印机将广泛用于制造缝线和复合材料样本，用于机械实验，以验证分析和数值模型或为分析和数值模型提供输入。在仿生工程领域，虽然在理解生物结构的机械响应方面取得了实质性进展，但具有精确控制的界面形态和材料组成的人工复合材料的制造仍然是一个具有挑战性的目标。3D打印技术的发展为克服这一困难提供了机会。因此，这项研究不仅将探索天然复合材料的新增韧和能量耗散机制，而且所开发的方法揭示了一种使用3D打印作为工具来探索基础工程和科学问题以及仿生设计新概念的范例。

The research will explore a new strategy for the creation of mechanically sound connections between individual parts of plates and shells. This approach is inspired by findings in natural materials where individual parts are often found to be connected to each other om jigsaw-puzzle-like structure. One such example are seed coats of some plants, which consist of stiff, nominally planar building blocks that are connected to one another via compliant zigzag seams. These seams are called suture interfaces. This investigation will focus on how the network of suture interfaces contributes to toughness, damage-tolerance, and the efficiency of load transmission between building blocks. Engineering analysis, computer simulations and experiments on 3D printed plate and shell systems will be conducted. The knowledge gained from this research will provide guidelines for designing new lightweight and damage-tolerant material systems with broad engineering applications in aerospace, naval, architectural structures, ground vehicles, and armor. The interdisciplinary nature of the research will involve diversified participants and will expose students to the areas of mechanics, materials, biology and manufacturing. The research will employ an integrated analytical, computational and experimental methodology to systematically quantify the mechano-morphological effects in the bio-inspired jigsaw composite plates and shells. A hybrid analytical and finite element modeling approach will be used to predict the mechanical behaviors of suture interfaces and jigsaw composites, including the mixed-mode damage initiation and evolution, two basic failure mechanisms of suture interfaces and the failure mechanism transition. A 3D multi-material printer will be extensively used to fabricate suture and composite specimens for mechanical experiments to verify or provide inputs to the analytical and numerical models. In the area of bio-inspired engineering, although substantial progress has been made on understanding the mechanical response of biological structures, the manufacture of artificial composites with precisely-controlled interface morphology and material composition remains a challenging goal. The development of 3D printing technology provides an opportunity to overcome this difficulty. Therefore, this research will not only explore a new toughening and energy-dissipation mechanisms of a natural composite material but also the methodology developed reveals a paradigm for using 3D printing as a tool to explore fundamental engineering and scientific questions and new concepts in biomimetic design.