Grun Tobias B, Nebelsick James H
Department of Geosciences, University of Tübingen, Hölderlinstraße 12, 72074 Tübingen, Germany.
R Soc Open Sci. 2018 May 9;5(5):171323. doi: 10.1098/rsos.171323. eCollection 2018 May.
The clypeasteroid echinoid skeleton is a multi-plated, light-weight shell construction produced by biomineralization processes. In shell constructions, joints between individual elements are considered as weak points, yet these echinoid skeletons show an extensive preservation potential in both Recent and fossil environments. The remarkable strength of the test is achieved by skeletal reinforcement structures and their constructional layouts. Micro-computed tomography and scanning electron microscopy are used for microstructural and volumetric analyses of the echinoid's skeleton. It is shown that strengthening mechanisms act on different hierarchical levels from the overall shape of the skeleton to skeletal interlocking. The tight-fitting and interlocking plate joints lead to a shell considered to behave as a monolithic structure. The plate's architecture features distinct regions interpreted as a significant load-transferring system. The internal support system follows the segmentation of the remaining skeleton, where sutural layout and stereom distribution are designed for effective load transfer. The structural analysis of the multi-plated, yet monolithic skeleton of reveals new aspects of the micro-morphology and its structural relevance for the load-bearing behaviour. The analysed structural principles allow to be considered as a role model for the development of multi-element, light-weight shell constructions.
饼海胆类海胆的骨骼是一种通过生物矿化过程形成的多板、轻质的外壳结构。在外壳结构中，各个元件之间的关节被视为薄弱点，但这些海胆骨骼在现代和化石环境中都显示出广泛的保存潜力。测试的显著强度是通过骨骼增强结构及其构造布局实现的。微型计算机断层扫描和扫描电子显微镜用于海胆骨骼的微观结构和体积分析。结果表明，强化机制在从骨骼的整体形状到骨骼互锁的不同层次上起作用。紧密配合和互锁的板状关节导致外壳被视为一个整体结构。板的结构特征有不同区域，被解释为一个重要的载荷传递系统。内部支撑系统遵循其余骨骼的节段划分，其中缝合线布局和立体骨分布是为了有效传递载荷而设计的。对多板但整体的骨骼的结构分析揭示了微观形态的新方面及其与承载行为的结构相关性。所分析的结构原理使（海胆骨骼）可被视为多元素轻质外壳结构发展的一个范例。
