Skip to content

Trepped Block Laminated Beam Across the Agger River

Refurbishment of "Lölsberger Steg"


The refurbishment and repair of ‘Lölsberger Steg’ in Overath included minor repairs in the section above the flood plain area. The major part of the project consists of the renewal of the main span corssing the Agger. For this part, we developed two alternatives. Verion 1 includes a protected timber structure with a main carrier as stepped and block laminated fishbellied girder. Version 2 includes a main structure made of two steel beams with cross beams of steel. The decking and railing of the bridge base on the existing elements made of Azobé (Ekki). The client chose the timber variant for ecological and aesthetic reasons.

The centerpiece of the bridge is the block laminated glulam beam as treppted fishbellied girder. It is made of Spruce GL28h and GL24h. The carrier is constructed as follows:
– Top layer Gl28h, section B / H = 84 / 36cm
– Middle layer GL24h, section B / H = 64 / 24cm
– Bottom layer Gl28h, section B / H = 44 / 12cm
The middle and bottom layer are arranged in accordance to the bending moment diagram.

Heimat- und Bürgerverein Overath e.V.

Year of construction

Length: 63,00 m
Width: 1,00 m
Length substitute: 20,00 m

Block laminated beam GL28h trepped in cross and longitudinal view. reinforcement against transversal tension by fully threaded screws. Decking made of Azobe planks. Protection against weathering using a metal sheeting on top and a sacrificial timber cladding.

Our services
Design planning, enigneering, structural planning, tender procedure, site management – service phase 1-9 according to German HOAI

Other views of the bridge