Scarf and splice joints enabled the joining of two elements lengthways. They were used when available materials could not provide the required piece length. Usually, wherever possible, they were applied in the least stressed cross-section because the joined elements could never achieve the same load bearing capability as that of a solid cross-section [6]. In historical structures, aside from elongating ground and capping beams in building frames [7], scarf and splice joints were used to elongate roof elements. Up until the introduction of glue laminated timber technology, this was the common method for elongating wood elements [8]. Today, carpentry joints are used inter alia in the case of restoring historical joints or where the material need to be replaced in heritage elements. It is possible to distinguish several basic types of scarf and splice joints in historical structures, which were applied depending on their location in the structure and on the forces, which they needed to transfer (Fig. 1).
A stop-splayed scarf joint (described inter alia in [11,12,13,14]) was a sophisticated form of joining elements lengthwise. However, it was commonly used in historical buildings. Elements joined along their whole length with so-called stop-splayed scarf joints are composite beams with a teethed joint (also known as built-up beams, which are described inter alia in [15,16,17]) (Figs. 2 and 3). They have been used since ancient times, e.g. in the construction of Roman bridges, and later in building elements forming wooden floors in town halls or churches, as well as in rafter framing right up to the end of the nineteenth century. A special development phase of this type of beam joint occurred during the Italian Renaissance period. With development of adhesive wood technologies, such as glue laminated timber, this type of joint is used today only in strengthening and repairing historical buildings. There are no rules provided in the available literature related to forming and dimensioning such elements.
Common Wire Splices And Joints Pdf Download --
The results of research carried out at the University of Bath in the UK by the team of Walker, Harris, Hirst et al. [51] concern static behaviour of scarf joints, which are most common in historical structures across England. The joints research includes: under-squinted butt in halved scarf with two pegs, side-halved and bridled with two pegs, stop-splayed and tabled scarf with key and four pegs, and face-halved and bridled scarf with four pegs. The authors underline that making the openings for the pegs involved displacement in both the elements being joined in order to allow tightening of the joint after insertion of the peg (see for example [9]). The joints analysed are presented below (Fig. 8). 2ff7e9595c
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