Structural Elements with LVL KERTO®-S+Q - From Bridge to Building Construction Design
by L. Haefner, Dr.-Ing.
IBH-SE: L+T+R, Sophie-Charlottenstr. 9-10, 14059 BERLIN
1. Overview of Pedestrian and Bike Bridge with LVL Kerto-S/-Q
The bridge is a 4-span construction (Graphic 1) with the first span of a load bearing roof section above the walkway and 3-span T-beam construction with an open walkway. The bridge was built with modern wood composite of Kerto®, laminated veneer lumber (LVL) with available large boards bonded together. Steel elements are frames, truss girder and plate connections.
The first, covered span is the technical remarkable part with a weak torsion folded plate, built with LVL of type Kerto-Q wood composite boards and steel bracing truss girder underneath. There is load transfer from walkway by the hanger (vertical beam) into the timber roof and from there to steel frame at two supports. Bridge bearings are placed on a concrete pile wall and on middle pier (Graphic 2).
For the uncovered part of this modern bridge was used high-strength material of wood composite Kerto-Q with large boards and Kerto-S beams for continuous 3-span walkway. With the advantage of large Kerto-Q boards and overlapping as a 3-span continuous beam has been build (Graphic 3).
2. Building Construction of a Rooftop at Berlin + Tall Timber Building
With the experience of a bridge follows heightening of an existing building as rooftop with the advantage of construction material Kerto and foremost pre-fabrication. There are pre-fabricated walls with Kerto-Q boards as airtight construction. The rib-slab elements are covered with special concrete layer and connected as Timber-Concrete-Composite (TCC) for fire protection. This construction method results in an assembly with a high noise control structural element. Furthermore, there are research results here presented for tall Timber Building design with façade optimization against wind and vibration loading.
3. Advantage of LVL Kerto-S/Q and Construction Details
There are the dimension and material data with properties such as
• Large boards with width * length = 1.80m * 23m, and various thickness.
• High strength timber material, orthotropic timber properties.
• Transfers strength capabilities for Kerto-Q for load transfer,
With basic “pressure bonding” and/or “screw-pressure bonding” large pre-fabricated structural wall and plate elements can be produced. The required bracing of any building can be solved by Kerto-S or much better as bearing walls with Kerto-Q (Graphic 4).
Also, for our research activity some essential references and literature are following presented.
Berlin, Dec. 31st, 2017
Barber, D. (2017): “Fire Safety and Tall Buildings – What`s Next”, Report to ASCE/SEI Structures Congress 2017, at Denver Colorado / U.S.A, April, 8th 2017, published in ASCE/SEI Proceedings, edited by J.G, Soules, Vol. 3, p. 556 - 569.
Bodig, J., Jayne, B. A. (1982): “Mechanics of Wood and Wood Composites”, 1st Edition, Van Nostrand Reinhold Company Inc., New York, p. 1 - 712.
SOM Report (2013): “Timber Tower Research Project”, Chicago, p. 1 ÷ 105.
Tannert, T. and Moudgil (2017): “Structural Design, Approval and Monitoring of a UBC Tall Wood Building”, Report to ASCE/SEI Structures Congress 2017, at Denver Colorado/U.S.A, April, 8th 2017, published in ASCE/SEI Proceedings, edited by J.G, Soules, Vol. 3, p.541 - 547.