Quality proves its worth
Jan 07, 2015
Sewer rehabilitation with SPR™ technology in Budapest, Hungary
With the consistent application of Spiral-Wound technology along several kilometers and for several years, Budapest has developed into a model city for Spiral-Wound pipe rehabilitation in Europe. The individual versions of the technology are suitable for different rehabilitation requirements with various diameters and shapes of sewer networks. Since 2010, approx. 18,861 m lengths of round as well as custom shaped profiles have been rehabilitated in Hungary and thereof 5,869 m beneath the Budapest city centre.
With the latest large profile rehabilitation project in the north-east of Budapest, the technology demonstrated again its wide range of capabilities. SEKISUI SPR rehabilitated together with its construction partner Agriapipe 565 metres of the strong corroded cement pipe with dimensions of 1400 x 2100 mm underneath the Pozsonyi Street. From the end of June to the beginning of October 2014, the pipe rehabilitation team repaired the egg-shaped sewer while maintaining a controlled live flow using the SPR™ Spiral-Wound pipe method.
The Spiral-Wound technology from SEKISUI SPR is already a familiar rehabilitation solution for the city of Budapest. The city has, since 2010, been impressed by the low costs, brief construction times as well as the longevity of the trenchless rehabilitation technology. After approx. 18,861 metres of successfully rehabilitated sewer pipes in Hungary and 5,869 m underneath the city life of Budapest, the Spiral-Wound method has proven its worth. Most recently, the Spiral-Wound pipe system showed its potential in the trenchless rehabilitation of 54 m of the egg-shaped sewer underneath Pozsonyi Street in 2013, and of an additional 565 metres in the summer of 2014.
"Since the sewer network of Budapest features various diameters and shapes, the Spiral-Wound technology with its different method versions is the ideal solution for the operators. This provides a rehabilitation process for all standard diameters in circular form, but in particular, with SPR™, also for the most diverse custom shapes, such as box or mouth-shaped, or even egg-shaped profiles, up to 5500 mm," commented Mr. Zoltán Varga, the Managing Director of Agriapipe Ltd, the construction partner. A central aspect in the selection of the Spiral-Wound method several years ago was also the requirement for the necessary structural integrity of the old structures to be re-established. Additionally it is an advantage that work can be carried out exclusively through existing manholes so that there are hardly any hindrances for the local residents as well as the street traffic of this megacity during the rehabilitation.
Year |
Location |
Spiral-Wound Technology |
Diameter (mm) |
Length(m) |
2010 | Budapest, Hungary | SPRTM RO | 800 | 273 |
2010 | Budapest, Hungary | SPRTM | 1350 | 31 |
2010 | Budapest, Hungary | SPRTM EX | 300 | 700 |
2011 | Budapest, Hungary | SPRTM | 1200,1800 | 156 |
2011 | Budapest, Hungary | SPRTM EX | 300 | 668 |
2012 | Budapest, Hungary | SPRTM EX | 500,400,300 | 917 |
2013 | Budapest, Hungary | SPRTM EX | 200,300,400 | 2505 |
2013 | Budapest, Hungary | SPRTM | 1400/2100 | 54 |
2014 | Budapest, Hungary | SPRTM | 1400/2100 | 565 |
Variants of Spiral-Wound technology
The Spiral-Wound pipe method is based on the principle of the mechanical in-situ production of a liner made of extruded plastic profile strips. The process produces liners for nominal widths of 200 to 5500 mm by a winding machine that pushes the Spiral-Wound profile in the host pipe or – depending on the process version – leads the Spiral-Wound liner through the structure. By standard, PVC-U profile strips are installed with the Spiral-Wound pipe technologies with differently structured locking systems, depending on the procedure.
One exception is the SPR™ PE method in which an HDPE profile strip is used and the mechanical lock is replaced by a PE welding connection. The three Spiral-Wound pipe methods SPR™, SPR™ EX and SPR™ RO, which have been used in Budapest for years as a model for future-oriented sewer rehabilitation, differ in particular according to two important features: On the one hand with regard to the static stability, on the other hand, the positioning of the winding machine in the winding process.
The well-established Spiral-Wound pipe methods SPR™ EX and SPR™ RO wind the liner without annular space into the host pipe. In the end a close-fit liner with minimal cross-section reduction is created that allows an increased flow rate due to the low roughness of the material. If an annular space is created during the winding process, the necessary grouting with high-strength grout serves as a structural component on the SPR™ liner or with sealing material as insulation for the SPR™ PE method.
SPRTM |
SPRTM PE |
SPRTM EX |
SPRTM RO |
|
Diameter |
800 – 5500 mm
|
900 – 3000 mm
|
200 – 750 mm
|
800 – 1500 mm
|
Material |
PVC-U
|
HDPE
|
PVC-U
|
PVC-U
|
Shape |
Circular, egg, mouth and any other
|
Circular
|
Circular
|
Circular
|
Annular space |
Annular space
|
Annular space
|
Close-fit
|
Close-fit
|
Winding machine |
running ahead
|
firmly stationed
|
firmly stationed
|
running ahead
|
Host pipe condition class type II
Budapest Sewage Works Pte Ltd. operates the complete 5400 km long sewer system of the metropolis. Underneath there is also a 730 m long cement pipe with a diameter of 1400 x 2100 mm that drains collected rain and wastewater of the district 13, in the north-east of Budapest into the wastewater treatment plant. The combined wastewater sewer, which has been in operation since 1907, exhibits material fatigue due to non-stop operation over the years as well as cracks and damage due to corrosion. Bacteria and caustic sulphuric acid inside the pipes have attacked the cement even though the concentration is low due to the common draining of wastewater and rainwater. The damage also decreased the structural stability of the concrete sewer.
The egg-shaped sewer in need of rehabilitation is located under the very busy main road, Pozsonyi Street, in the 13th district of downtown Budapest. In addition, buses come through every 5 minutes in the bus lane between the two lanes in each direction. For rehabilitation through standard manholes, only a few meters around the access needed to be blocked off for the equipment and the rehabilitation vehicle. There was hardly any hindrance for traffic above ground even though the rehabilitation project underground was rather large and many metres in length.
Winding process during controlled live flow
The 565 metre long ailing sewer section was rehabilitated with the SPR™ Spiral-Wound method by winding a steel-reinforced profile strip of PVC-U into a new highly resistant plastics inner layer directly within the host pipe. For that, the guide frame of the Spiral-Wound machine was lowered through a standard manhole into the rehabilitation section, installed into the host pipe directly and adjusted to the egg-shaped profile of the sewer while taking the statically required annular space into account. The 52 Spiral-Wound pipe spools stationed one after another above ground supplied the winding machine continuously with profile strips via the standard manhole. The winding machine moved forward with every rotation by one profile width and locked the profile with a tongue-and-groove mechanism to create a watertight liner. Once one of the 52 Spiral-Wound pipe spools was used up, the new profile strip was joined in a portable butt welding unit.
The winding process was carried out during controlled live flow in the old sewer. A masonry wall was built at the upstream point so that the pump could transfer the combined wastewater into the following sewer section. After about 250 metres of rehabilitated sewer section, the stone wall was moved from the upstream point into the middle of the rehabilitation section to control the live flow for the remaining metres to be rehabilitated. The goal was to maintain a water level of maximum 15 cm. Heavy rainfall posed a challenge occasionally as the water level rose to 1 metre and the winding process had to be interrupted briefly. Since the winding machine always remained stationed in the old sewer, winding could resume promptly after the water level had dropped and the pipe was cleaned.
Grouting
The winding process aimed to generate a defined annular space between the Spiral-Wound liner and the host pipe, which was filled with a high-strength grout in a subsequent work step. The thickness of the annular space is determined according to the following principle: as little annular space as possible, but as much annular space as necessary for the required static properties. In this case, the thickness was between 50 mm and 80 mm.
After the Spiral-Wound liner was completed, a bracing system was installed so that the annular space could be filled. The bracing frames positioned the Spiral-Wound pipe liner according to the static requirements and thus prevented buoyancy, a positional deviation and deformation during the subsequent grouting. The annular space was sealed after each 80-metre section of installation length and filled up in layers with special grout to re-establish the static features of each section.
Durable corrosion protection of the concrete structure
In the long term, the new rehabilitated pipe offers an important operational advantage: Since the steel-reinforced plastic Spiral-Wound pipe liner is not a temporary aid for installation, but rather remains a fixed design component of the rehabilitation solution, it permanently protects the host pipe and the filled-in annular space grout against mechanical abrasion and attack by the combined wastewater. In the end, the SPR™ Spiral-Wound pipe liner therefore serves as formwork for a new mineral grouting of the old sewer and as a reliable protective coating over many years that separates the concrete structure from the combined wastewater. The smooth and abrasion-resistant surface of the SPR™ liner will improve the hydraulic capacity minimum for the next 50 years of continuous operation and compensates for the minimal cross-section reduction of the host pipe.
A fine conclusion
As the final step, the reconnection of the grouting sections and laterals were done as usual. During this year's rehabilitation project, the SPR™ technology not only proved to be durable and economic, but also a rehabilitation method that can be accomplished comparatively quickly. After the city ordered the works, successful completion of the rehabilitation of the sewer section was planned for just 15 weeks later on the construction schedule.
More News and Articles
Aug 28, 2024
News
ITpipes Secures $20M to Transform Water Infrastructure Management
ITpipes announced it has secured $20 million in equity financing from Trilogy Search Partners and Miramar Equity Partners.
Known for its trusted and user-friendly platform, ITpipes …
Aug 26, 2024
News
Professor Dr.-Ing. Dietrich Stein
With deep sadness we announce the loss of our founder and partner Prof Dr Dietrich Stein at the age of 85.
Engineers around the globe are thankful for his dedication to the inventions in the fields of sewers, …
Aug 26, 2024
News
PPI Releases New Installation Guide for PE4710 Pipe
PPI’s MAB-11-2024 Covers HDPE Water Pipelines Up to 60-in. Diameter and 10,000-ft Long Pulls
Developed by the Municipal Advisory Board (MAB) – and published with the help of the members of the …
Aug 23, 2024
News
Faster wide-scale leak detection now within reach
Mass deployment of connected leak loggers is being made possible by the latest technology, writes Tony Gwynne, global leakage solutions director, Ovarro
Water companies in England and Wales are …
Aug 21, 2024
News
Kraken awakens customer service potential in water
The innovative customer service platform Kraken has made a successful transfer from energy to water. Ahead of their presentation at UKWIR’s annual conference, Portsmouth Water chief executive …
Aug 19, 2024
News
Predicting the toxicity of chemicals with AI
Researchers at Eawag and the Swiss Data Science Center have trained AI algorithms with a comprehensive ecotoxicological dataset. Now their machine learning models can predict how toxic chemicals are …
Aug 16, 2024
News
Goodbye water loss: Trenchless pipe renewal in Brazil
Pipe renewal in Brazil
How do you stop water loss through leaks in old pipe systems without major environmental impacts and restrictions? The answer: with trenchless technology, or more precisely …
Aug 14, 2024
Article
Impact of high-temperature heat storage on groundwater
In a recently launched project, the aquatic research institute Eawag is investigating how the use of borehole thermal energy storage (BTES) affects the surrounding soil, the groundwater …
Aug 12, 2024
News
Watercare completes East Coast Bays sewer link
Watercare has successfully finished the final connection on the East Coast Bays link sewer at Windsor Park in New Zealand.
Much of the East Coast Bays sewer link was installed using horizontal directional …
Aug 09, 2024
Article
Innovative water solutions for sustainable cities
Cities need to become more sustainable and use their water resources more efficiently. Managing water in local small-scale cycles is one possible solution. A new white paper by Eawag, the University …
Aug 07, 2024
Article
How digital technologies contribute to universal drinking water
Digital water technologies have an important role in ensuring universal access to safe drinking water by 2030, that is according to a new report from the World Health Organisation. …
Aug 05, 2024
News
Knowledge transfer on sustainable water infrastructure in India
India’s fast-growing cities need an efficient infrastructure for water supply and wastewater disposal. A research cooperation, is therefore supporting the development of a sustainable …
Contact
SEKISUI SPR Group
Lena Tiedeken
Julius-Müller-Str. 6
32816 Schieder-Schwalenberg
Germany
Phone:
+49 (0) 162/ 105 07 86