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Precise lifting of heavy steel bridge components

Darmstadt/St. Ingbert

After the start of the steel construction assembly on September 24th, 10 segments of the Grumbachtal bridge have now been assembled. The individual steel components with weights of up to 140 tons were manufactured at our headquarters in Darmstadt to the highest quality standards and delivered to St. Ingbert by heavy-duty transporters.

Massive mobile cranes with a maximum load capacity of 500 tons lifted the heavy steel bridge segments precisely onto their piers. Following the lifting assembly, the individual sections were welded together.

In the coming weeks, further parts of the steel structure (in total 4800 tons) will be delivered and installed, so that the superstructure will arrive at the second abutment before Christmas. Erection of the last two shots is scheduled for early 2021.

105 years of experience and loyalty

“Long-serving employees, their experience and skills, are the backbone of any company”, with these words Peter Brechtelsbauer, Managing Director of Donges SteelTec GmbH, introduced the honouring of the company’s anniversaries.

Thomas Kloose and Werner Spielberger started their professional lives at Donges on 1 September 1980. In the 40 years of their membership of the company, they have witnessed many changes, acquired experience and know-how and always felt committed to the company.Thomas Kloose trained as a technical draughtsman at Donges, was employed on a permanent basis after completing his training and today passes on his knowledge and passion for steel construction to young entrants as training manager in the technical office. Werner Spielberger began as a steel construction fitter and is today, as a safety specialist, responsible for the safety of his colleagues both within the company and on the construction sites.

Sabine Kadic has been working as a design engineer at Donges for a quarter of a century and looks back proudly on many renowned steel construction projects, such as the Lehrter Bahnhof in Berlin, the Airbus hangar Finkenwerder or the hot-dip galvanizing hall 3 in Salzgitter, on which she worked.

A heartfelt thank you to all those celebrating an anniversary for their loyalty and commitment to our company and all the best for the future!

 

Donges SteelTec receives order for the replacement of the Thulba viaduct

The bidding consortium Adam Hörnig GmbH and Donges SteelTec GmbH has been awarded the contract for the replacement of the Thulba viaduct. This involves two superstructures for the A7 motorway bridge between Würzburg and Fulda in the Bad Kissingen/Oberthulba section of the motorway. The bridges, each with a total length of 460 m, up to 53 m above the valley, will cross the A7 over the Thulba as well as various forest and farm roads.

The replacement for the 7-span bridge, which was completed in 1968 and is now to be demolished, is a steel composite bridge that is pushed in lengthwise. The steel construction tonnage amounts to a total of 6,000 tons. “We are very proud to have been awarded the contract together with our long-standing partner, Adam Hörnig GmbH”, said Stephan Langer, Managing Director Bridge Construction of Donges SteelTec GmbH. “Such particularly challenging structures are our hobbyhorse and we are delighted to be able to help design such magnificent bridges”. The client is the Autobahnamt Nordbayern, for whom Donges SteelTec has already built the Heidingsfeld and Breitengüßbach viaducts. Construction will start in the autumn of 2020; the construction time is estimated at around six years.

We build with steel and would like to pass on our passion for this material.

 

Darmstadt, 01.09.2020. Donges SteelTec GmbH welcomed six trainees at the start of the new training year. Two technical system planners and four construction mechanics are starting their professional careers in our steel construction company in Darmstadt.

For years, training at Donges SteelTec has been in great demand. “We are delighted that we are again able to accompany so many young people at the start of their careers and thus build up our own junior staff”, said Joachim Abt, industrial training manager at Donges SteelTec GmbH.

During the three-and-a-half-year training period, the construction mechanics are familiarized in the company’s own training workshop with the usual processes of steel construction production and steel processing such as turning, drilling and milling and welding. In the company’s technical office, the technical system planners learn how to work with modern 3D/2D CAD programs, how to create overview and workshop drawings and how to create parts lists and NC data for the production machines. During the workshop phase, the design engineers to be trained acquire knowledge of steel processing. Company training projects and an extensive training program round off the apprenticeship.

“We have been building steel bridges and innovative steel structures for over 140 years. Each construction is individual and a small masterpiece. Getting young people excited about it is both a claim and a challenge for us” says Thomas Kloose, head of training in the technical office at Donges SteelTec.

New railway overpass over the river Steinach: Installation is proceeding successfully

In the middle of May the assembly of the new railway overpass over the Steinach in Balingen has started. First of all a supporting structure was assembled on which the newly manufactured bridge sections could be placed and welded. After the carriageway slabs were placed on the support structure as the first components, the two large trussed slabs were lifted in. Assembly was not easy here because the 44-metre long trusses had to be delivered backwards under the old railway bridge. This proved to be a big problem due to the low clearance height: The trucks could not pass completely under the bridge. The solution was to lift the long trusses under the old existing bridge using a 700 tonne crane. The crane thus unloaded the trucks, placed the components next to the support structure, erected them and lifted the 64-tonne trusses onto the support structure. A great deal of sensitivity was required here, as the railway traffic on the existing bridge was not stopped during this time.

After this assembly phase, support structure was completed and then the smaller trusses were lifted in. Currently, the entire bridge is being welded and the corrosion protection is being completed. The work is proceeding according to schedule.

Following the steel construction work, the client will dismantle the old existing bridge and will move the new bridge to its final position.

 

Construction of the third hot-dip galvanizing production line at Salzgitter Flachstahl progressing rapidly

Darmstadt/Salzgitter, July 3, 2020.
In the meantime, the steel structure of hot-dip galvanizing hall 3 at Salzgitter Flachstahl has been almost completely assembled. The assembly of the roof and wall elements runs at full speed. Our technicians on site have met the very tight schedule with great commitment.  The project is fully on schedule. The photos of the process hall show in an impressive way the structural engineering challenge of this construction project.

Key data of the process hall: length 275 m, height 45 m, width 44 m, 4000 t steel construction, 12,000 m² roof area, 25,000 m² wall area

Second construction phase successfully installed

With the lifting of the A46 Westring bridge, an eventful April came to an end for our bridge builders. In the night from April 25 to 26, the 2nd construction phase of the motorway bridge was successfully installed.

Two 300 t cranes at the abutments and a 750 t crane below the bridge ensured that the steel components could be lifted in. The parts were delivered over the bridge, which had already been built in the 1st construction phase, by means of heavy transporters, slewed by two cranes and set down on the new piers.

First, the two outer bays were lifted, each consisting of two hollow boxes with a length of approx. 37 m.  Then followed the end cross beam and the cross beam on the pier. Thus the two hollow boxes were connected with each other.

Finally, the bridge was completed by the two 18 m long central components which were delivered underneath the bridge and lifted in place with the 750 t crane in a single lift.

The total length of the three-span composite steel bridge is 105 m with a total superstructure width of 36 m. 1000 t of steel were used for the entire steel construction of the structure.

Another milestone successfully completed

The second shifting of the bridge north of Bamberg was successfully completed by our technicians on the weekend 17th/18th April 2020.

In the course of the replacement and reconstruction of the Bridge 93b of the BAB A73 Bamberg-Lichtenfels, the steel construction (approx. 1,400 tons) of the steel composite structure was shifted by 45 m over the B4 and the railway line to be crossed with the beginning of the closing break of the German Railway on Saturday and reached the auxiliary pier as planned.

On the following Sunday, the remaining shift took place with a total of 70 m to abutment 40. During the next weekend operation the bridge was then stacked by 1.30 m to its intended final position.

The composite steel bridge consists of two separate superstructures (section 1, Lichtenfels carriageway and section 2, Bamberg carriageway). The two separate superstructures are antimetrically designed, geometrically particularly challenging trough structures made of steel with a concrete roadway slab. The total length of the three-span bridge is 150 m with a total superstructure width of 37.20 m. For the entire steel construction of the structure 2800 tons of steel are required.

 

Successful lifting of the new railway bridge

In Riederich, two thick plate bridges with an individual weight of approx. 37 tons were placed on the new abutments. The railway overpass consists of two separate superstructures. Each superstructure is designed as a trough bridge with thick plate. A walkway is attached to one side of each of the two superstructures. The span of the bridge is approx. 6.10 m, the construction height is 0.8 m. Each of the superstructures has a width of 4.48 m. The footpaths have widths of up to 1.19 m.

The bridge sections have been placed on top of addition stacks and remain on these until the bearings have been cast. Afterwards the footpaths were added.

In this state the bridge is now waiting to be moved to its final position together with the two abutments.

Lifting of the new railway overpass

In the night from Good Friday to Saturday the lifting of the new railway overpass over the Hattenbergstraße in Mainz took place.

During the day, two 500-ton cranes were used to dismantle the temporary bridges before the assembly of the new bridges could begin in the evening.

The railway overpass consists of three separate superstructures. Each superstructure is designed as a trough bridge with thick plate.  On each of the two outer superstructures a walkway is attached on one side. The span width of the bridges is approx. 22.00 m, the construction height is 1.5 m. Each of the superstructures has a width of approx. 4.50 m. The footpaths have widths of up to 1.35 m.
This resulted in unit weights of up to 135 tons.

The bridges were set down on allowance stacks and then the bearings were cast.

The Hattenbergstraße railway overpass went into operation on schedule.