Folded plate structures made of cementitious composites

利用折纸原理的折叠技术在工程学科中越来越受欢迎，并在具有承载功能的折叠结构领域开辟了新的机会。结合新型水泥基复合材料与柔性织物连续增强，折叠技术提供了一种创新的方法，设计和制造的轻质结构的原则的基础上，形状跟随力。由于制造过程的高度适应性，该方法适合于大规模定制，因为它符合高可变性和经济生产的要求。在第一个项目期间，已经开发了水泥基折叠结构的设计和制造方法的基本组成部分。新算法的折叠过程的模拟和几何基础的找形方法已在数学上制定和实施的插件在模拟工具包称为oricrete。基于所进行的模拟，设备控制的折叠过程中已经开发和验证的单弯曲壳的基础上的吉村折痕图案。目标配置已通过折痕线中的灌浆固定。灌浆折痕线的力学性能进行了测试，弯曲，拉伸，横向和剪切载荷。承载行为进行了分析，使用有限元模型自动生成的oricrete工具包。第二个项目周期的目标是设计和生产方法的扩展，有效的静态基础上的形状发现算法和制造策略结合几种折叠方法。所提出的概念的可行性将代表演示对象进行评估。特别是，应在oricrete工具包中开发和实施反映折痕线刚度特性的找形方法。这一发展将解决普遍需要的有效形式发现的方法，反映了机械性能和可折叠性的限制。所发展的几何与静力学找形方法与演算法，将被用来分析几种已知折痕图样的成形性与静力学性能。将通过承载性能的几何和物理非线性分析来验证找形方法。所开发的制造策略将用于生产几个薄的折叠试样的模拟结果的实验验证。作为该项目的最终目标，一个由几个折叠部分组成的折叠屋顶结构将作为开发方法的演示。

The folding technique exploiting principles of origami is becoming increasingly popular in engineering disciplines and opens up new opportunities also in the field of folded structures with load-carrying function. In combination with novel cement-based composites continuously reinforced with flexible textile fabrics, the folding technique provides an innovative method for design and manufacturing of light-weight structures based on the principle of form follows force. Due to the high adaptivity of the manufacturing process the method lends itself to mass-customization as it complies with the requirements on high variability and economic production. In the first project period, basic components of the design and manufacturing methodology for cement-based folded structures have been developed. New algorithms for the simulation of the folding process and for geometrically based form-finding methods have been mathematically formulated and implemented as plug-ins in the simulation toolkit called oricrete. Based on the conducted simulations, devices controlling the folding process have been developed and validated for singly curved shells based on the Yoshimura crease pattern. The target configuration has been fixed by grout in the crease lines. The mechanical properties of the grouted crease lines have been tested for bending, tensile, transverse and shear loadings. The load-carrying behavior has been analyzed using a finite element model automatically generated by the oricrete toolkit. The goal of the second project period is the extension of the design and production methodology with efficient statically based form-finding algorithms and manufacturing strategies combining several folding approaches. The feasibility of the proposed concepts is to be evaluated on behalf of demonstrator objects. In particular, form-finding methods reflecting the crease line stiffness properties shall be developed and implemented in the oricrete toolkit. This development will address the general need for efficient form-finding methods reflecting the mechanical properties and foldability constraints. The developed methods and algorithms for a geometrically and statically based form-finding will be employed to analyze the formability and static performance of several know crease patterns. The form-finding methods will be validated by geometrically and physically nonlinear analysis of the load-carrying behavior. The developed manufacturing strategies will be used to produce several thin folded specimens for the experimental validation of the simulation results. As a final goal of the project a folded roof structure consisting of several folded segments will be built as a demonstrator of the developed methodology.