Fracture and post-fracture behaviour of glass and laminated glass structures

夹层玻璃作为承重结构在建筑和工程建设中的应用越来越重要。除了用于大面积的玻璃幕墙外，夹层玻璃结构还可用作防坠落装置、可行走的玻璃地板以及梁柱形式的重要承重构件。新型结构玻璃的设计和优化需要了解材料和结构特性。特别是，玻璃的断裂机理的理解和可靠的预测分层夹层玻璃的结构断裂后的行为是必需的。目前，结构玻璃的施工和设计是基于对已批准设计方法的保守处理。达姆施塔特工业大学结构力学与设计研究所在夹层玻璃结构的制造和实验研究方面有多年的经验。德累斯顿工业大学结构分析研究所专注于数值模型的开发和实施。结合大量的实验专业知识和全面的经验，在数值模型是一个有前途的方法来开发模型，以预测层压玻璃结构的断裂和断裂后的行为。热预应力玻璃的断裂特性和主要影响参数的识别系统的实验文件是调查的重点。在此基础上，分析和数值模型的开发，以描述和可靠地预测断裂过程。分析模型建立在对整个结构进行能量分析的基础上，用于预测断裂模式。采用新的相场模型描述裂缝形态和断裂过程。首先，为了理解和描述玻璃断裂的基本过程，建立了玻璃微碎片形成的连续介质力学模型。随后，该配方被转移到一个板单元，这样，在结构层面上的断裂过程的模拟是可能的。在玻璃中的断裂过程的记录和建模之后，用作夹层玻璃中的夹层的聚合物膜的行为是实验研究和数值建模的焦点。最后，研究了玻璃和聚合物的结合对断裂的影响。该研究项目的最终目标是为夹层玻璃结构的断裂和断裂后特性开发一个系统的实验数据库，以及通过裂纹演变和材料建模相结合来描述所观察到的行为的数值概念的开发、实施和应用。

The use of laminated glass as load bearing structure in buildings and engineering constructions gains increasing importance. Next to the use for extensive glass facades, laminated glass structures are applied as fall protection, walkable glass floor as well as essential load bearing component in form of beams and columns.The design and optimisation of novel structural glazing requires knowledge in material and structural behaviour. Especially, the understanding of the fracture mechanism in glass and the reliable prediction of the structural post-fracture behaviour of layered laminated glass is required. The construction and design of structural glazing is currently based on a conservative handling of approved design approaches. The Institute of Structural Mechanics and Design of TU Darmstadt has experience in manufacturing and experimental investigation of laminated glass structures for many years. The Institute for Structural Analysis of TU Dresden is focused on the development and implementation of numerical models. The combination of large experimental expertise and comprehensive experience in numerical models is a promising approach to the development of models to predict the fracture and post-fracture behaviour of laminated glass structures.Initially, the fracture mechanical behaviour of sole glass structures is investigated. The systematic experimental documentation of the fracture characteristics of thermally pre-stressed glass and the identification of the main influence parameters are in the focus of the investigation. Based on this, analytical and numerical models are developed, in order to describe and reliably predict the fracture process. The analytical model is founded on an energetic analysis of the whole structure for the prediction of the fracture pattern. The novel phasefield model shall be adopted for the description of the fracture configuration and the fracture process. At first, a continuum mechanical model is developed for the genesis of a micro-fragment, in order to understand and depict the fundamental fracture processes in glass. Subsequently, the formulation is transferred into a plate element and, this way, the simulation of the fracture process on the structural level is enabled. After documentation and modelling of the fracture processes in glass, the behaviour of the polymeric membrane, which is used as interlayer in laminated glass, is in the focus of the experimental investigation and the numerical modelling. Concluding, the combination of glass and polymer with respect to fracture is investigated. The final goal of the research project is the development of a systematic experimental data base for fracture and post-fracture characteristics of laminated glass structures as well as the development, implementation and application of a numerical concept for the description of the observed behaviour via the combination of crack evolution and material modelling.