Lightweight ceiling structures made of layered high-perfomance concrete

由层状高性能混凝土制成的轻质天花板结构

• 批准号: 198117966
• 负责人: Professor Dr.-Ing. Manfred Curbach
• 金额: --
• 依托单位: Institut für Massivbau
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/198117966?language=en
• 关键词: Lightweight; ceiling; structures; made; layered

The aim of the requested extension period is the exploration of the load bearing behaviour of form optimized layered two-way slabs. Due to the stratification of the cross-section, the materials can be arranged according to the existing stress distribution along the cross-section height. Consequently, each of the applied materials can be put to its best possible use. The high compression and tensile stresses at the top and bottom layer of the sandwich structure are carried by thin layers of suitable concrete or by a reinforcement. In the centre of the cross section, which is under less stress, the load transfer can be achieved through special lightweight concretes. These concretes join the top and bottom layer shear rigid. Through an additional form optimization of the bottom layer according to the principle form follows force, the efficiency of the layered slab can be further increased.Fundamental research carried out in the first funding period served to show that slabs with a layered cross section have a significantly lower self-weight than conventional slabs. The main focus of the work was on choosing an ideal material combination. In particular, the core layers load bearing capacity has to be sufficiently high to guarantee the shear rigid connection of the top and bottom layer (without shear reinforcement). In experimental investigations of one-way slabs, the load bearing behaviour of layered slab elements was analysed and the transition zones between the different failure modes were determined. In the requested project period these fundamental findings are to be transferred to two-way slabs. Furthermore, the influence of layered cross-sections on the biaxial load-transfer is to be determined. Toward this aim, two-way slabs will be numerically and experimentally investigated. The mutual verification of experiment and numerical model will be carried out continually. Subsequently, a force flow optimized two-way slab will be developed. An engineering model and a construction recommendation will be provided for the design of form optimized layered slabs. Finally, the insights gained will be transferred to multi-span systems. Based on the results from project Cross Sectional Adaption for Rod-Shaped Elements, which an extension period has also been applied for, a demonstrator will be developed to prove that the form optimized members can be consolidated in one spatial structure.

请求延长期限的目的是探索形式优化的分层双向板的承载性能。由于横截面的分层，可以根据沿横截面高度的现有应力分布来布置材料。因此，每种应用的材料都可以得到最好的利用。夹层结构顶层和底层的高压缩和拉伸应力由合适的混凝土薄层或钢筋承受。在受力较小的横截面中心，可以通过特殊的轻质混凝土实现荷载传递。这些混凝土连接顶层和底层抗剪刚性。根据形状追随力的原理，通过对底层进行额外的形状优化，可以进一步提高分层板的效率。第一期资助期间开展的基础研究表明，具有分层截面的板具有显着的性能。比传统板的自重更低。这项工作的主要重点是选择理想的材料组合。特别是，核心层的承载能力必须足够高，以保证顶层和底层的抗剪刚性连接（无抗剪加固）。在单向板的实验研究中，分析了分层板单元的承载行为，并确定了不同失效模式之间的过渡区域。在所要求的项目期间，这些基本发现将被转移到双向板中。此外，还需要确定分层横截面对双轴载荷传递的影响。为了实现这一目标，将对双向板进行数值和实验研究。实验与数值模型的相互验证将持续进行。随后，将开发力流优化的双向板。将为形状优化分层板的设计提供工程模型和施工建议。最后，获得的见解将转移到多跨系统中。基于杆形构件横截面适应项目的结果（该项目也已申请延长期限），将开发一个演示器，以证明形式优化的构件可以合并在一个空间结构中。