With its project “Urban Development No. 175, for the Former Railroad Site West of Werkstrasse,” the German city of Soest set the stage for establishing new industrial estates within the scope of ongoing urban development. In its capacity as developer, the municipal company Kommunale Betriebe Soest AÖR had specified the use of FBS materials for the drainage works as prerequisite for contract award. Berding Beton, as an FBS member plant, won the contract and was able to deliver the concrete and reinforced-concrete pipes, as well as manholes for the construction of the sewer in the FBS quality specified.
All FBS member plants manufacture structural concrete components based on the prescribed FBS quality guidelines. The invitation to tender stipulated execution in accordance with FBS, which guarantees an especially long service life, since stricter requirements that significantly exceed those of the standard must be satisfied. The superior properties that are crucial here for FBS structural concrete components are the results of tightness of the pipes and pipe connections, great bearing capacity, effective hydraulics, and resistance to corrosion.
Good collaboration of all project participants
FBS planned a new pipe-laying film presentation to emphasize these benefits, among other advantages. In its search for a suitable leading role, the film producers hit on the Soester construction project, implemented entirely with FBS materials and conducted on a site where optimal site conditions existed. After reaching an agreement with all parties involved in the project, shooting started in September of 2015. In all relevant individual steps, the film presented prime examples showing the entire process of pipe laying in accordance with good engineering practice and with professional installation of standard FBS products for wastewater discharge lines and sewers.
The Soester construction project was planned by the engineering firm KLT Consult in Lippetal, Germany. Based on the previous jointly executed proj-ects, the new collaboration was able to proceed on the basis of good experience gained in the past. The same applied to the expertly executed development works, for which the building contractor Feldhaus, with headquarters in Schmallenberg, Germany, was responsible. The family company is now in its fourth generation and has been successful on the market for 100 years. The highly qualified company employees implemented all works in a highly professional way, including during shooting throughout the film.
Clinkered manhole components
The concrete products of FBS quality required for the construction of the sewer were manufactured at the Berding supplier plant in Möhnesee, Germany, which specializes in the manufacture of pipes and manholes. Products used included FBS reinforced concrete pipes, DN 500 to DN 900 mm, with circular cross section; FBS manhole bottoms, DN 1,000 to DN 2,000 mm; FBS sections, DN 1,000 to DN 2,000 mm; and FBS manhole bottoms, DN 2,000 mm, of special design with a height of up to 2,900 mm. The manhole bottoms of special design with a useful height of 2,600 mm were manufactured to the customer’s specifications and were used with elevated inlets to take account of local conditions. This is a special feature, since standard FBS manholes have a useful height of 1,300 to a maximum of 1,800 mm. The manhole bottoms involved not only individually manufactured sections, but also included single-part elements.
Final execution of the manholes took place manually, also on specific request of the customer. The channels and the banquettes of the manholes were manufactured in the Berding plant in Möhnesee and were clinkered in accordance with the specifications of the consulting engineers Ingenieur-Büro KLT. The elevated inlets can be fitted into the manholes of special design.
Butt joint limiters guard against spalling
During laying of reinforced-concrete pipes with circular sections, with an individual weight of 2.75 metric tons and a length of 3.0 m, wooden butt joint limiters were used to guard against accidental spalling when joining pipes. Due to their temporary function, the limiters were attached to the flared-out ends simply using a lubricant. A come-along was employed to enable optimal application of forces while pulling the pipes together. The firmly installed sliding-ring seals in the flared-out ends further facilitated joining the pipes.
The laying of reinforced-concrete pipes with foot was the only measure exclusively carried out for the film to demonstrate the advantages of this technique. Here, plane embedding over the entire surface in accordance with DIN EN 1610 is sufficient without extensively shaping the bottom of the trench. The pipes, thanks to their positional stability, remain in their intended position, and backfilling and/or supplementary tasks are easier – with the result that the use of pipes with foot is in most cases much more cost-efficient.
Following the successful conclusion of the shooting, the construction measure was completed in October. The new FBS pipe-laying film graphically shows how high-performance and durable sewer pipes can be installed with the use of advanced concrete and reinforced-concrete pipes.