Assessment of intermediate support of multi-span sandwichpanels

多跨夹芯板中间支撑评估

• 批准号: 401248346
• 负责人: Professor Dr.-Ing. Jörg Lange
• 金额: --
• 依托单位: Fachgebiet Stahlbau
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/401248346?language=en
• 关键词: Assessment; intermediate; support; multi; span

Sandwich panels in construction are made of two thin steel faces which are connected by a heat-insulating core material, usually polyurethane-foam (PUR) or mineral wool. In Germany approximately 20 million m² are installed for walls and roof covering annually. They are characterized by a very good combination of waterproofing, thermal insulation, and load-bearing. The complete wall or Roof structure is combined in one single element, which also carries live loads such as wind and snow. Due to the prefabrication and the low self-weight large panels can be mounted in a single lift. This leads to continuous beams. In this application a combination of large bending moments and bearing forces result at the internal bearing points. The bearing force reduces the ultimate moment capacity (Moment-bearing force-interaction). This reduction can only be assessed experimentally. A generally approved design provision which takes the local loading situation into account is not available. Goal of this research project is the identification of the decisive mechanical relationships that affect the interaction. Furthermore a design model shall be developed in order to avoid further experimental analyses. Most available design models are based on a theoretical approach in which the ultimate moment (e.g. the wrinkling stress) is calculated assuming no interaction. This has to be seen skeptical, since the exact calculation of the wrinkling stress is still an unsolved problem. However the theoretical wrinkling stress in undisturbed regions might be helpful for the assessment of the interaction-problem. Up to now most theoretical approaches for the calculation of wrinkling stresses depending on bearing loads are based on a global analysis of the bending moment which is superimposed on the local bearing loads. A look into the hitherto existing publications shows a large difference in the models and the results combined with a small accordance with experimental results. This proofs the need for further research.

建筑中的夹层板由两个薄钢面制成，这两个薄钢面由隔热芯材连接，通常是聚氨酯泡沫（PUR）或矿棉。在德国，每年约有2000万平方米的墙壁和屋顶覆盖物被安装。它们的特点是防水、隔热和承重的很好结合。完整的墙或屋顶结构组合在一个单一的元素，它也可以承受风和雪等活荷载。由于预制和低自重，大型面板可以安装在一个单一的电梯。这导致连续梁。在该应用中，内部支承点会产生大的弯曲力矩和支承力。承载力降低了极限弯矩承载力（弯矩-承载力-相互作用）。这种减少只能通过实验来评估。没有一个普遍认可的设计规定，考虑到当地的负载情况。本研究项目的目标是确定影响相互作用的决定性机械关系。此外，应开发设计模型，以避免进一步的实验分析。大多数可用的设计模型都是基于理论方法，在该方法中，极限弯矩（例如，弯曲应力）是在假设没有相互作用的情况下计算的。这是值得怀疑的，因为精确计算的应力仍然是一个未解决的问题。然而，在未扰动区的理论应力可能有助于相互作用问题的评估。到目前为止，大多数计算轴承载荷下的弯曲应力的理论方法都是基于叠加在局部轴承载荷上的弯矩的整体分析。到目前为止，现有的出版物的外观显示了很大的差异，在模型和结果相结合的小符合实验结果。这证明需要进一步研究。