Glued-in basalt FRP rods under combined axial force and bending moment: An experimental study

Performance of glued-in-rod connections in cross-laminated timber

“…Although many studies e.g. [13,16,43,57] have shown that the GiR strength increase with the anchorage length, some studies have reported that this increase is not linear due to stress concentrations [43,58,59]. Gehri [45] suggested moving the anchorage zone of steel rod away from the surface of timber into the inner part by leaving a gap at the face of the drilled hole where no adhesive is applied along the anchorage length, thus preventing the mechanical interlock around this zone, see The rod diameter (d) is one of the most commonly investigated GiR parameters.…”

“…Likewise, Steiger et al [42] found the failure load to reduce when the edge distance was less than 2.3d. Elsewhere [57], the optimum edge distance of 3.5d was identified as the distance with greatly reduced splitting failure and maintained strength. The edge distances were evaluated in [67] and it was recommended that greater than 3d should be used to prevent splitting failure of timber.…”

“…Sufficient spacing between rods is necessary to avoid premature timber failure [57]. In previous work [13], spacings of 3d, 4d and 5d were used and the load-carrying capacity of the connection increased with larger spacing and large spacing resulted in the yielding of the rod.…”

“…For example, the pull-pull test configuration (Figure 2.3) is a common loading set-up for connections parallel to the grain. For connections such as the moment-resisting connections where bending forces have to be accounted for, a pull-bending test set-up is appropriate [57,75]. Variations of the pull-pull test can also be made to fit specific specimen configuration.…”

“…EWPs offer these possibilities. To avoid wood splitting and glue line failure, the test specimens were designed with the minimum requirements for edge distance and glue line thickness as reported for solid timber and glulam [41,57], 4d and 1.6 mm were used.…”