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Dowel type timber joints are popular in timber construction and they can be used in timber trusses and moment resisting frames (i.e. beam-to-column joints). Bearing strength is an important design parameter that influences the strength of each failure mode a joint can experience. Therefore, in order to enhance the load carrying capacity of dowel-ty...
Contexts in source publication
Context 1
... shear and splitting failure modes were observed in the plain timber joints (see Fig. 6). The ductile bearing failure mode occurred when the timber that was in contact with the bolt crushed due to the bearing strength of the timber being reached. As the bolt moved into the crushed timber, the load was maintained. After completion of the test, irrecoverable deformation of the bolt hole was then observed (see Fig. 6a). A ...
Context 2
... timber joints (see Fig. 6). The ductile bearing failure mode occurred when the timber that was in contact with the bolt crushed due to the bearing strength of the timber being reached. As the bolt moved into the crushed timber, the load was maintained. After completion of the test, irrecoverable deformation of the bolt hole was then observed (see Fig. 6a). A brittle shear failure mode was observed when a wedge of timber was displaced from the specimen in the direction of the load. The width of the wedge and the diameter of the bolt in this case were approximately the same length. Specimens that failed in shear typically contained three cracks that propagated parallel to the timber ...
Context 3
... of the wedge and the diameter of the bolt in this case were approximately the same length. Specimens that failed in shear typically contained three cracks that propagated parallel to the timber grain direction: two shear cracks that formed on the bearing side of the joint and one splitting crack that formed on the opposite side of the joint (see Fig. 6b). As cracking began to occur, the joint swiftly lost its strength. The brittle splitting failure mode occurred when a single splitting crack propagated through the bolt hole (see Fig. 6c). This was the result of the perpendicular-to-grain tensile strength of the timber being reached. In addition, there was a sudden loss of strength ...
Context 4
... timber grain direction: two shear cracks that formed on the bearing side of the joint and one splitting crack that formed on the opposite side of the joint (see Fig. 6b). As cracking began to occur, the joint swiftly lost its strength. The brittle splitting failure mode occurred when a single splitting crack propagated through the bolt hole (see Fig. 6c). This was the result of the perpendicular-to-grain tensile strength of the timber being reached. In addition, there was a sudden loss of strength when this failure mode ...
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Citations
... The peak strain tends to lie in the middle line of surface (see Fig. C.24 L-M-D8) or localize between the net and gross shear lines (see Fig. C.24 L-M-S10) [84,85]. This is consistent with the observed two types of failure mode, shear and splitting failure [62,[86][87][88][89]. Additionally, it can be reflected by the strain distribution of bolt head that the rope effect can be modeled by the proposed FEM model. ...
... Pioneering works about strengthening and stiffening of dowelled connections were performed using injection of resins in proximity of the holes [12], applying external toothed metal plates to share embedment between steel and timber [13], or reducing installation gaps with expanded steel tubes [14]. More recently, CFRP (Carbon Fiber Reinforced Polymer) laminates and GFRP (Glass Fiber Reinforced Polymer) fabrics were investigated as local strengthening of traditional dowels [9,10,15] and large diameter tubes [16]. Lately, local strengthening to avoid shear plug failure was explored by gluing a squared steel plate with polyurethane adhesive [13]. ...
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