Flück Holzbau AG Work Platform, Wangen bei Dübendorf

The Starting Point

The new work platform at Flück Holzbau AG in Wangen near Dübendorf is 15 meters long, 7.5 meters wide, 36 centimeters thick, weighs 18 tons—and is made mostly of wood. It is used to process the wooden elements from the newly installed TW-Agil 3000 joinery system, which has an input width of 3,000 millimeters.

The Challenge

The enormous spans combined with the high live loads posed a major challenge for the timber construction. The platform consists of three cross-laminated timber panels that have been glued together using TS3 technology to form a single large panel. To relieve stress on the adhesive tension side and minimize deflection and vibrations, the panel was eccentrically pre-stressed with tension rods.

The height of the platform’s support beam, which spans the entire 15 meters, was limited. The reason: The feed mechanism for the panel processing system was to be located on the underside, and on the upper side, the beam was not to protrude too high above the platform so that the forklift could remove the packages of wood.

The girder height therefore had to be limited to 700 millimeters. For this reason, a high-performance girder made of beech laminated veneer lumber was used. However, this resulted in excessive deformation. Therefore, two steel tension rods were inserted into the girder in a fishbelly shape and pre-stressed. This allowed the girder to be raised in height while also making it stiffer and reducing deformation.

Construction data

• Cross-laminated timber panels: 40 m³
• Construction beech laminated veneer lumber: 3 m³
• Platform area: 110 m²