5. STRUCTURAL DESIGN OF CONNECTIONS Table 5.4. Minimum spacings, end distances and edge distances for 6-30 mm dowels 32. 5.3 WOOD FAILURE MODES OF CONNECTIONS 5.3.1 Risk of splitting due to connection forces at an angle to the grain of face veneers When a force in a connection acts at an angle to the grain (see Figure 5.9) the possibility of splitting caused by the tension force component, FEd ∙sin α, perpendicular to the grain, shall be taken into account. For timber, glulam and LVL-P the following should be satisfied: Fv,Ed ≤ F90,Rd (5.1) (EC5 8.2) Figure 5.9. Inclined force transmitted by a connection (modified from EC5 Figure 8.1) where F90,Rd is the design splitting capacity; Fv,Ed ≤max{█(F_(v,Ed,1)@F_(v,Ed,2) )┤ (5.2) (EC5 8.3) Fv,Ed,1 and Fv,Ed,2 are the design shear forces on either side of the connection caused by the connection force component (FEd ∙ sin α) perpendicular to the grain. v,Ed ≤ max { v,Ed,1 v,Ed,2 (5 v,Ed,2 are the design shear forces on either side of the con connection force component (FEd ∙ sin α) perpendicular to the grain. Figure 5.8. Inclined force transmitted by a connection (modified from (Kuva_107_a splitting force in connections 190314, Ku in connections 190314, Kuva_107_c splitting force in connections 19 Design splitting capacity is calculated from the characteristic splitting equation (4.3), in subsection 4.1.6. For softwoods, the characteristic arrangement shown in Figure 5.8 should be taken as: 90,k =14 ∙ √ ℎe (1 − ℎ ℎ e) [ ] (5 where F90,Rk is the characteristic splitting capacity [Ν]; he is the loaded edge distance to the centre of the most di h is the timber member height, [mm]; and Spacing or distance, see Figures 5.4-5.7 Angle α Minimum spacing or end/edge distance LVL-P / GLVL-P or LVL-C / GLVL-C edge face LVL-C / GLVL-C wide face Spacing a1 (parallel to grain) 0° ≤ α ≤ 360° (4 + 3│cos α│) d a) (3 + │cos α│) d Spacing a2 (perpendicular to grain) 0° ≤ α ≤ 360° 3d 3d Distance a3,t (loaded end) -90° ≤ α ≤ 90° max (7d; 105 mm) b) max (4d; 60 mm) c) Distance a3,c (unloaded end) 90° ≤ α < 150 ° 150° ≤ α < 210° 210° ≤ α ≤ 270° a3,t │sin α│ 3d a3,t │sin α│ (3 + │sin α│) d Distance a4,t (loaded edge) 0° ≤ α ≤ 180° max [(2 + 2 sin α) d; 3d] max [(2 + 2 sin α) d; 3d] Distance a4,c (unloaded edge) 180° ≤ α ≤ 360° 3d 3d a) minimum spacing a1 may be reduced to 5d if fh,0,k is multiplied by a1 / (4 + 3│cos α│) d b) minimum end distance a3,t may be reduced to 7d for d < 15 mm if fh,0,k is multiplied by a3,t /105 mm c) minimum end distance a3,t may be reduced to 4d for d < 15 mm if fh,0,k is multiplied by a3,t / 60 mm LVL Handbook Europe 149
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