Preloaded bolted connections made of stainless steel under fatigue loading in civil engineering structures

土木工程结构疲劳载荷下不锈钢预载螺栓连接

• 批准号: 521501197
• 负责人: Professorin Dr.-Ing. Natalie Stranghöner
• 金额: --
• 依托单位: Institut für Metall- und Leichtbau
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/521501197?language=en
• 关键词: Preloaded; bolted; connections; made; stainless

In the construction industry, structures and bolted connections made of stainless steel are increasingly being used as load-bearing components in steel construction, e.g. in bridge structures, roadway crossings and coastal protection systems, due to their excellent corrosion resistance in aggressive environments. While in the past mainly austenitic stainless steel was used, in recent years austenitic-ferritic stainless (duplex) steel has also been increasingly used. However, preloaded bolted connections made of stainless steel in fatigue-loaded structures have so far not been considered feasible due to ignorance of the expected preload losses as a result of the viscoplastic deformation behaviour of the components as well as fears regarding cold welding effects. For these reasons, the project does not only focus on the fatigue loading capacity, but also considers the principle tightening behaviour of the boltin assemblies including tightening parameters in order to prevent premature failure of the bolts. As further aspects, the viscoplastic deformation behaviour, the interfacial pressure of the clamping package to avoid plastic deformations and thus ultimately too high preload losses are considered. The central research objective of this application is thus the development of concepts for describing and recording the load- and structure-dependent non-linear behaviour of preloaded bolted connections made of metal construction bolting assemblies made of austenitic stainless and duplex steel in the typical diameter range M12 to M36 under fatigue loading for use in the construction industry. Ultimately, the aim is to transfer these findings into boundary conditions for an optimised bolting assembly type made of stainless steel for use in the construction industry. To achieve the research objectives, an extensive programme of experiments on the aspects mentioned is planned, which will be extended by numerical FE parameter studies with FE models validated on the experiments. Finally, an analytical model for describing the viscoplastic deformation behaviour is to be developed, interfacial pressures for clamping packages made of stainless austenitic and duplex steel for use in the construction industry are to be derived, the tightening behaviour of prestressed bolted joints as a basis for developing suitable criteria for describing the requirements for minimum ductility, The fatigue strength of stainless steel bolts under tensile and shear loads will be determined and boundary conditions for an optimised type of bolting assemblies for preloading for use in civil engineering will be developed on the basis of the results obtained.

在建筑行业中，由不锈钢制成的结构和螺栓连接越来越多地用作钢结构中的负载组件，例如在桥梁结构，道路穿越和沿海保护系统中，由于它们在侵略性环境中具有出色的耐腐蚀性。虽然过去主要使用了奥氏体不锈钢，但近年来，奥氏体 - 特洛米特不锈钢（双链）钢也越来越多地使用。然而，由于组件的粘膜变形行为以及对冷焊接效应的恐惧，由于对预期的预加载损失的无知以及对冷焊作用的恐惧而导致预期的预加载损失，因此尚未被认为是可行的。由于这些原因，该项目不仅关注疲劳载荷能力，而且还考虑了包括拧紧参数在内的玻丁组件的原理拧紧行为，以防止螺栓的过早故障。作为进一步的方面，粘膜变形行为，夹紧套件的界面压力，以避免塑性变形，因此最终考虑了过高的预加载损失。因此，该应用的主要研究目标是开发概念，用于描述和记录由典型的直径范围M12至M36制成的金属结构螺栓固定组件制成的预加载螺栓连接的载荷和结构依赖性的非线性行为。最终，目的是将这些发现转移到边界条件中，以使其在建筑行业中使用不锈钢制成的优化螺栓装配类型。为了实现研究目标，计划了一项关于提到方面的实验计划，该计划将通过数值FE参数研究扩展，并在实验中验证了FE模型。 Finally, an analytical model for describing the viscoplastic deformation behaviour is to be developed, interfacial pressures for clamping packages made of stainless austenitic and duplex steel for use in the construction industry are to be derived, the tightening behaviour of prestressed bolted joints as a basis for developing suitable criteria for describing the requirements for minimum ductility, The fatigue strength of stainless steel bolts under tensile and shear loads将根据获得的结果，将确定和优化类型的螺栓固定组件类型的边界条件用于土木工程的预加载。