Giant Barrel Javorník - use of glued laminated timber

INTRODUCTION AND A DROP OF HISTORY
The building is a modern replica of a barrel that stood here as part of a tourist lodge. The Javornický barrel used to measure 12x14 m and was transported to the Liberec region from the Jubilee Exhibition celebrating 50 years of the reign of Franz Joseph I in Vienna in 1898, where this exhibition display served as a wine cellar. Wilhelm Huebel, the innkeeper from Dlouhé Mosty near Liberec, purchased it for 600 gold coins, had it dismantled, and transported it by rail in four wagons from Vienna to Liberec. The grand opening of the Giant Barrel took place on June 18, 1899. It provided refreshments to hikers on the Ještěd ridge for decades and was still in operation after World War II. The definitive end came in 1974 when the entirely wooden structure succumbed to fire.

DESCRIPTION OF THE BUILDING
This is the eastern part of the recreational sports complex Obří sud in Javorník. As indicated by the name, it is a building in the shape of a lying barrel, which has four above-ground floors. The first floor hosts a restaurant, while the others are used for accommodation. In the front part, the individual floors are connected by a common space reaching the full height of the building, which is illuminated through a glazed "lid." The wooden supportive structure of the glazed wall, formed by posts, purlins, and a perimeter beam, is set directly on the foundation, and stability is ensured by a joint connection with the reinforced concrete skeleton.
All buildings in the complex share a unified architectural expression. The northern facade of the giant barrel is built with lightweight ceramic blocks. The facade is insulated with mineral wool panels, partially covered with stone cladding and elsewhere with wooden siding. In both cases, it features a ventilated outer shell. The ventilated air layer is connected to the external environment by ventilation openings in the gables. The shell is made of folded titanium-zinc sheet.

WOODEN STRUCTURE
The basic dimensions of the structure are a diameter of 15 m across the "belly," and a length of 15 m. The shell structure is supported by 17 curved rafters "hoops," mostly with a profile of 100 x 300 mm at about 0.9 m intervals. The radius of curvature of the rafters varies according to their position on the barrel shell, with 10 different radii used, ranging from 6.55 to 7.55 m. Longitudinally, the object is bordered in the area of the glazed lid by three tie beams of 200 x 460 mm, two with a radius of 21.60 m and one measuring 26.30 m. In areas where there is no reinforced concrete skeleton, the position of the rafters is stabilized by braces.
The supporting structure of the lid's wall consists of three columns, the largest measuring 12.3 m long and 200 x 440 mm in profile, along with purlins of 160 x 160 mm.
For the resulting aesthetic effect and favorable static properties, most connections are realized with bolts and internal plates placed in grooves.

ANCHORING

ASSEMBLY
Due to the relatively small radii of the rafters, the arcs were divided into two or three parts, adapted for transport from production to the construction site. Considering the timeline of the entire construction, it was necessary to begin assembly during the winter, when the peak for freight transport was inaccessible. Therefore, a helicopter was used to transport the completely pre-prepared wooden elements to the top of Javorník.

During the actual assembly, there were certain height inaccuracies of the crowns and reinforced concrete structures to which the wooden structure is anchored. Due to the addition of more snow, the partially completed structure was covered and preserved until spring. Under more favorable conditions, the southern part of the barrel was completed, including the finishing of the wooden formwork with a thickness of 24mm made of impregnated boards.

Source: http://www.areal-obrisud.cz/
Author of the article: Eva Grochalová, TAROS NOVA s.r.o.