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Flooding prevention using the example of the City and metropolitan area of Manila

Manila, capital of the Philippines, has around 1,8 Mio inhabitants and is situated in the agglomeration “Metro Manila” with a total of 12,9 Mio citizens. The immense population pressure since the middle of the 20th century caused an uncontrolled expansion of the city Manila and the surrounding conurbation.

The planning and construction of the installations of sewage discharge and treatment systems as well as storm water distribution could not keep up with this growth. Thus, drainage systems yes do exist, but do not meet in any way to the objectives of integral urban drainage systems. Especially the inadequate hydraulic dimensioning of the distribution pipelines, which are mostly done in the diameter of DN/ID 900 mm, regularly lead to overload flooding in a lot of districts of Manila.

People trying to escape the enormous amounts of sewage watersPicture 1: People trying to escape the enormous amounts of sewage waters

The hydraulic failure of the systems is even intensified by the need of relining and repair, wrongly constructed manholes, false installation of the pipelines as well as root infiltration and blockings. On basis of the applied regulations of the German association for water management, waste water and waste (Deutsche Vereinigung für Wasserwirtschaft, Abwasser und Abfall e. V. (DWA)) and DIN norms possibilities for a safe discharge of waste water as well as the protection against flooding shall be presented.The current situation in Manila is difficult: Due to the demographic development of the last decades in the agglomeration of „Metro Manila“ and the city of Manila, the populated areas have multiplied. This expansion of populated areas happened without a sustainable planning of a secure waste water discharge and storm water distribution system. Thus, consequently, the protection of humans and goods against flooding in the residential areas and a proper discharge of waste water were not ensured. The sewage system based on a sewage and storm mixed system was extended with the growing settlement but without adapting the existing system to the hydraulic additional load. Natural discharge ways and retention areas were overbuilt without creating sufficient countervailing measures. The still existing open water channels were often limited and restricted by dense constructions. Bridges without sufficient freeboard, encroaching buildings of all kinds as well as deposit of rubbish is existent, which reduces the drainage system width considerably.

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Ukrainian pipe market - experience that matters

Leaders of Ukrainian market of construction and installation of pipelines are ready to work on international level

On November 2016 in Lviv, Ukraine, there was a solemn ceremony of opening a new tramline connecting residential district Sykhiv with central part of the city. Only few people attending the ceremony knew that it was preceded by another event, not less important for the city’s life. It was replacement of old 520-meters underground non-pressure sewage collector located directly under the future tramline track. Replacement of the old sewage collector on the Stusa Street was the biggest infrastructural project implemented in the period of Ukraine’s independence over last 26 years.

Site during installationPicture 1: Site after installation

Worn-out condition of the old collector could have caused damage of the road bed above it. That’s why Lviv City Council and Lvivvodocanal organization decided to urgently replace the old collector with a new one. This difficult task was assigned to INSTALPLAST HV company and its subdivision INSTALBUD which performs works on construction and installation of internal and external pipelines, natural gas pipelines and sewage networks. Replacement works were done according to the project designed by German specialists. The works started in June 2015 and were accomplished in July 2016. Pipes PE of DN 1600 mm SN10 were used for a new collector. These pipes were manufactured by INSTALPLAST on its own equipment purchased from leading German company KRAH.

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Krah Pipes App

First Krah App for Android OS.
After many requests from a lot of Krah Pipe users, we started to develop our own little tool to support Krah customers and partners worldwide. A little app (available on Google Playstore) provides many tools of the complete environment of Krah Pipes. Like easy hydraulic calculations, short guidelines for electro-fusion, providing electro fusion bar codes on your mobile, volume calculation of storm-water retention tanks, etc.

Now, the beta version is available, simply search for “Krah Pipes” in your PlayStore or click here or on the image beside. In case you need more calculations or have any suggestions of which information should be in the app, please send us an email, and we’ll try to add the new feature in nearly “no-time”. Your help / feedback is absolutely necessary to have a tool you need and not a tool we like. By the way, the tool will also work offline. All ideas can be sent as remarks in Google PlayStore or via email to Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!.

Krah Pipes App



Extensive earthquake dynamic fitness test

1. Preface

One of the most used arguments for plastic pipe systems is the flexibility and durability. If a question appears about earthquake fitness, the plastic pipe industry normally replies by showing damage-statistics. And indeed, the statistic results are very convincing, especially with damage statistics of rigid pipe systems. In the last editions of our IMPROFIL magazine we published many reports regarding earthquakes (mainly from our friends in Japan)- but a practical orientated dynamic test of a complete plastic pipe system with all aspects of different jointing methods, fittings and constructions has never been done before.

Seismic regionalization of Russian FederationPicture 1: Seismic regionalization of Russian Federation

Thanks to the initiative of Krah Pipes Estonia, the well-known Russian JSC Research Center of Construction in Moscow has performed an extensive test program to investigate the earthquake fitness of the full Krah Pipe System with seismic intensity of 7-9 magnitudes. For the complete technical report please contact the management of Krah Pipes Germany directly (email: Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!).
Below please find the summarized technical report with the original title:

“Conduction of dynamic tests of conduits system including pipes, fittings, containers, wells, and pump stations of trade mark “KRAH PIPES” with assessment of the opportunity of their application in the regions of Russian Federation with seismic intensity 7-9 magnitudes”.

2. Introduction

The technical report is using the results of experimental researches of polyethylene conduit elements of the trade mark “KRAH PIPES”, designed for outdoor sewerage, disposal of waste water and ventilation. The tests were conducted on the stand which was specially designed by JSC Research Center of Construction, Research Institute of Building Constructions. The stand is a pendulum-type platform vibrator.

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Flexibility or flattening test

What does it means and why should a pipe fulfil the requirements?
Today the requirements for a sustainable pipe system have changed, not always the cheapest solution is the best for a country. More and more designers and engineers dare to search for the technically best product for a project, at very reasonable costs. Also the cost aspect changed from single costs to the „lifetime cost“– from cradle to crave, including all.

So, which support for a designer or a quality control department does the so called flexibility test or flattening test mean? How is the test-procedure and how should the result be valued? In several international and national standards like EN13476, DIN16961, ISO 21138 or the ASTM F-894 a link to these tests is given – but why?

Basically the test will check how flexible a pipe can be, without having any irreversible damages on the pipe. This pipe property will give safety to the designers against overloading of the pipe or ground-movements occurred by earthquakes or unexpected soil settlement.

The standards for the test: The flexibility test is ruled in ISO 13968 and the flattening test is ruled in ASTM F894 8.6.

Deflection at 30%
Picture 1: Deflection at 30%

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