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Holz als Roh- und Werkstoff

, Volume 65, Issue 1, pp 71–77 | Cite as

Influence of initial moisture induced stresses in multiple steel-to-timber dowel joints

  • Johan SjödinEmail author
  • Carl-Johan Johansson
ORIGINALARBEITEN ORIGINALS

Abstract

In this experimental study, multiple steel-to-timber dowel joints were first exposed to controlled climate changes. After being stored in climate chambers, the joints were loaded to failure. The major aim of the study was to investigate how and to what extent initial decrease in moisture in the joint area inducing shrinkage deformations affects the load-bearing capacity of joints of this type loaded in tension parallel to the grain. The load-bearing capacity of the joints was found to be reduced under these conditions, the decrease being greatest for joints in which steel dowels connected to a steel plate inserted into a slot in the wood restrained the shrinkage deformations during storage in the climate chamber. It was also found that the reduction in load-bearing capacity was greater and moisture-induced cracks were more frequent when the distance between the dowel rows were greater.

Keywords

Timber Steel Plate Climate Chamber Moisture Gradient Timber Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Einfluss Feuchte induzierter Spannungen auf die Tragfähigkeit von Holz–Stahl-Stabdübelverbindungen

Zusammenfassung

In dieser Arbeit wurden Stabdübelverbindungen von Holz mit Stahlteilen bestimmten Klimaänderungen ausgesetzt und nach Klimatisierung bis zum Bruch belastet. Hauptziel dieser Studie war es, herauszufinden, wie und in welchem Umfang sich eine durch Änderung der Holzfeuchte im Bereich der Verbindung induzierte Schwindverformung auf die Tragfähigkeit solcher Verbindungen bei Zugbeanspruchung in Faserrichtung auswirkt. Es zeigt sich, dass sich unter diesen Bedingungen die Tragfähigkeit der Verbindungen verringert. Dabei ergab sich die größte Abnahme bei den Verbindungen, bei denen die Schwindverformungen während der Lagerung in der Klimakammer durch die Stabdübel und die eingeschlitzten Bleche behindert wurden. Darüber hinaus zeigte sich, dass mit zunehmendem Abstand der Dübelreihen die Tragfähigkeit stärker beeinträchtigt wurde und mehr Schwindrisse auftraten.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.School of Technology and DesignVäxjö UniversityVäxjöSweden
  2. 2.SP Swedish National Testing and Research InstituteBorasSweden

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