The following figures show typical geometries of special glulam members. Additional member and building geometries can also be found in section “Construction Examples”.
For frequent case of curved glulam members as well as for all members that are subjected to extreme climatic changes, the lamella thickness is limited to 33 mm. Members with a camber of c ≤ l/100 (l = span width) are considered straight members and may therefore be made with lamella thicknesses up to 42 mm.
Curved members should typically be curved with a radius of at least 6.60 m. This corresponds to the minimum radius as per the former DIN 1052-1: 1988-04 for the typical lamella thickness of 33 mm. DIN 1052:2008 does allow smaller radii, but these can only be created with thinner lamellas (≤ 33 mm). As such lamellas must be ordered specially or have to be planed down from thicker lamellas with significant material losses, members with smaller curvature radii must be ordered sufficiently in advance and the additional manufacturing expense must be covered.
For tapered beams, the taper should always be situated in the area subject to compression stresses. If this is not desired for aesthetic reasons (as not to see the glue lines cut free by the taper), the taper can simply be covered by a single glued-on lamella.
Tapers exposed directly to weathering must be provided with an additionally glued-on lamella running along the entire length. As mentioned above, the weathering of glulam members should be avoided wherever possible.