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Authors:
Nehring, Gordon 
Document type:
Dissertation / Thesis 
Title:
Bemessung und Formfindung von kaltgebogenen Schalenstrukturen aus Dünnglas 
Parallel title:
Design and form finding of the cold bent shell structures of thin glass 
Advisor:
Siebert, Geralt, Univ.-Prof. Dr.-Ing. 
Referee:
Siebert, Geralt, Univ.-Prof. Dr.-Ing.; Belis, Jan, Prof. Dr. ir.-arch. 
Date oral examination:
26.11.2018 
Publication date:
03.07.2019 
Year:
2019 
Language:
Deutsch 
Subject:
Schale ; Dünnglas ; Träger ; Biegen ; Biegezugfestigkeit ; Prüftechnik ; Numerisches Verfahren ; Hochschulschrift 
Keywords:
Dünnglas, dünnwandiges Verbundglas, Bruchverhalten, Biegezugfestigkeit, Einachsig und doppelt gekrümmte Schalenform, Kaltbiegezustand, Lastzustand, Verbundwirkung, Relaxationsschubmodul, Bemessung, maximale statische Beanspruchbarkeit 
Abstract:
In this work, a dimensioning method for cold bent shell structures with double and uniaxial curvature of thin glass (t < 3mm) or thin-walled laminated safety glass (ttotal ≤ 5.38mm) is presented. For example, thin-walled laminated safety glass is cold bent onto shaping frame girder elements with subsequent continuous supports. In general, this leads to a spatial loading capacity of the single element under pressure and suction loads. For this purpose, the mechanical behavior of thin-walled laminated safety glass is investigated numerically and experimentally due to the time- and temperature-dependent states of cold bending and loading. The thermal internal stress or the characteristic value of the surface pressure stress equates to the maximum magnitude of the principal tensile stress on the glass element as a result of cold bending to avoid a possible crack growth. This can lead to glass breakage. By using two investigated methods for determining the thermal internal stress for different types of thin glasses, a qualitative description of their fracture behavior and structure can be made. The bending tensile strength of thin glass can not be determined with conventional testing methods which also account for the edge resistance. For this purpose, two testing methods have been developed which consider the geometrically nonlinear effects due to large deformations. The characteristic values of the bending tensile strengths are verified and validated on the basis of numerical and experimental investigations. Further tests are performed on small thin-walled laminated glass specimens to investigate the time- and temperature-dependent influence on their mechanical behavior due to uniaxial bending, which are subsequently compared to there results of larger uniaxially bent shell shapes. For both shell shapes, the results are validated by cold bending and loading tests on monolitic or laminated glass specimens. In addition, the results for the cold bending state are verified without consideration of stability effects. It is shown experimentally that the tested uniaxially bent laminated glass specimens had a full shear bonding due to cold bending state and a partial shear bonding behavior due to loading state. Finally, two comfordable dimensioning methods are presented to determine maximum static resistance ERd for both shell shapes. 
DDC notation:
693.96 
Department:
Fakultät für Bauingenieurwesen und Umweltwissenschaften 
Institute:
BAU 4 - Institut für Konstruktiven Ingenieurbau 
Chair:
Siebert, Geralt 
Open Access yes or no?:
Ja / Yes