Load-carrying capacity prediction of single rods glued into cross-laminated timber

Bonded-in Rods in Beech Glulam - Efficiency of a Recess in the Bondline

“…It is well known that the stress distribution along the length of the BiR is not uniform, with stress concentrations near the ends of the bondline. Recently, Vallée et al [16] studied the distribution of shear (τRL) and radial (σR) stresses along the bondline via numerical modelling of single BiR in CLT and glulam. Figure 5 illustrates the results for four different bonded lengths of a 12.7 mm (1/2-in) rod.…”

“…Fabris [12] studied the interaction of the stresses on the BiR performance and suggested that a recess of the bondline into the wood creating an unbonded zone near the outer end increases the stressed wood volume around the rod and hence improves the resistance to splitting, as shown in Figure 6. [16] Figure 6: Interaction of shear and transverse tensile stresses, modified from [12] The beneficial effects of a recess in the bondline on the pull-out resistance has been demonstrated experimentally by Salenikovich et al for BiR in CLT [17] and in glulam [18]. It allowed achieving a higher load capacity and minimizing the risk of splitting and other brittle failure modes, such as plug shear in CLT for rods bonded perpendicular to the grain.…”

“…Figure 5: Shear stresses, τRL, and radial stresses, σR, along the adhesive-wood interface, reference load F0= 100 kN, from[16] …”

Development of Comprehensive Testing Procedures for High-Performance Bonded-in Rods

“…Bonded-in rods in cross-laminated timber (CLT) are permitted according to the next generation of prEN 1995-1-1 Eurocode 5 [17]. However, Vallée et al [43] state that the prediction of the load-carrying capacity of bonded-in rods in CLT is more challenging than in glued-laminated timber due to the increased anisotropy arising from the orthogonal arrangement of the layers. Brittle failure modes of the rods with tear-out of wood blocks from the different layers of the CLT were observed in tests in [44]& [45].…”

In Brettsperrholz eingeklebte Stahlgewindestäbe – Experimente, numerische Simulation und Traglastbestimmung

“…Vallée et al [48] haben die Versuchsergebnisse von Tannert et al [36] mithilfe eines probabilistischen Ansatzes nachgerechnet. Anders als bei der BM, basierte die Modellierung auf der Annahme linear elastischen Werkstoffverhaltens.…”