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Sep 10, 2020 News James Brooks The water industry should continue to embrace new ways of working in a Covid-altered world and seize the opportunity to affect permanent change, a group of industry professionals heard.
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Sep 16, 2020 News Prof. Dr. rer. nat. Henner Hollert Since the beginning of the pandemic, research groups have been working on methods to detect SARS-CoV-2 viruses in wastewater to be used to monitor the degree of COVID-19 transmission among the population.
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Sep 17, 2020 News TEPPFA aisbl Members of CEN/TC 155, the Technical Committee coordinating standards activities for plastic piping and ducting systems within CEN, the European Committee for Standardisation, have unanimously re-elected Monica de la Cruz for a new mandate of three years.
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Sep 18, 2020 News Desiree Willis In July, a jubilant ceremony marked a milestone for southern Turkey’s arduous Bahçe-Nurdaği High-Speed Railway Tunnel. The first TBM-driven portion of tunneling using an 8.0 m (26.2 ft) diameter Robbins Single Shield machine is now complete. The 8.9 km (5.5 mi) long TBM tunnel was no easy bore, as it was excavated through some of the hardest and most abrasive rock ever encountered in the country.
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Sep 21, 2020 News Pablo Calabuig 20 cities across Spain monitor almost 10 million people daily to contain virus spread.
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Sep 27, 2023 News Jasamin Teuchler New e-learning module of the course BE-07 Investigation and Inspection of Sewers and Pipelines now available on UNITRACC!
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This report was prepared by the Trenchless Technology Center (TTC) for the U.S. Army Corps of Engineers, Engineering Research and Development Center (ERDC). Neither the TTC, the U.S. Army Corps of Engineers, nor any person acting on their behalf, makes a warranty, express or implied, with respect to the use of any information, apparatus, method, or process disclosed in this report or that such use may not infringe on privately owned rights; or assumes … |
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Although pipe ramming is an established and widely used trenchless method for installation of steel pipes and casings, especially under railway and road embankments, it has not been covered adequately with guidelines and standards. The need for guidelines in this area was demonstrated in a study Identification of Needs for User Guidance in Trenchless Technology Applications, which was prepared by the Waterways Experiment Station (WES) (now Engineering … |
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These guidelines have been prepared to assist owners, designers and contractors involved in new pipe installation projects to evaluate capabilities of pipe ramming for such projects and to design and carry out pipe ramming jobs effectively and safely, in conformance with project requirements and site conditions. The objective of the guidelines is to give a clear understanding of the method, outline important design and construction considerations, … |
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In a pipe ramming operation, a ramming tool attached to the rear of a steel pipe drives the pipe into the ground with repeated percussive blows. The method typically requires excavation of two pits. Before ramming, both the pipe and the ramming tool are placed into the insertion pit and lined up in the desired direction. Alternatively, the ramming can be launched without an insertion pit, if the ram is designed to start at the side of a slope. In … |
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Feb 28, 2006 Pipe ramming is typically used for pipe installation over relatively short distances, usually up to 150 feet [ISTT99] but installations longer than 300 feet have been successfully accomplished [NN00u], [NN99l], [NN96h], [Yachb], [Yachm]. The method is mostly used on pipes between 4 and 55 inches in diameter, although much larger pipes can be successfully rammed in the right ground conditions. Some examples of large-diameter casings installation show … |
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Feb 28, 2006 Although pipe ramming can be applied in a wide variety of soils, some soils are better suited for this method than the others. The most suitable soil conditions for pipe ramming are soft to very soft clays, silts and organic deposits, all sands (very loose to dense) above the water table, and soils with cobbles, boulders and other obstacles of significant size but smaller than pipe diameter (soils with cobbles can be in extremely wet conditions, … |
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Feb 28, 2006 Limitations generally come from the economical, environmental or safety aspects of the process. Compared to other casing installation methods, pipe ramming can be cost beneficial to the user. However, depending on the specifics of the project, the method may be more expensive than open-cut installation or directional drilling. Other drawbacks include high noise levels, which are typical for pipe ramming (if no noise protection is used), and sometimes … |
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Feb 28, 2006 Trenchless Method – Guidelines for Pipe Ramming Effects from Pipe Ramming on the Pipe and the Surrounding Environment Under each dynamic application of the force by the pipe ramming equipment, the pipe vibrates and the generated vibrations are transferred from the pipe to the soil particles. Ground vibrations associated with pipe ramming have not been studied so far. However, an extensive study of vibrational ground movement was carried out by the TTC for pipe bursting in pipe sizes ranging from 8 to 16 inches in diameter [Wage97]. With respect to the ground vibrations, … |
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Feb 28, 2006 Trenchless Method – Guidelines for Pipe Ramming Effects from Pipe Ramming on the Pipe and the Surrounding Environment Surface disruption associated with pipe ramming happens rarely because a solid, steel pipe is in the ground all the time and the soil within the pipe is not removed until later in the process. As a result, the creation of voids during construction or post-project settlement are drastically reduced. However, pavement sags or humps occur occasionally on the surface above an installation. The type and extent of surface disruption depend on the soil … |
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Feb 28, 2006 Trenchless Method – Guidelines for Pipe Ramming Effects from Pipe Ramming on the Pipe and the Surrounding Environment Pipes used for ramming are subjected to a dynamic (impact) force that is repeated a large number of times during the ramming operation. Under each dynamic application of the force, kinetic energy is transferred from the ramming tool to the pipe and the soil. Thus, in addition to the calculations of required jacking force, minimum pipe dimensioning and buckling safety of the pipe (done in conventional pipe jacking), a consideration needs to be given … |
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Pipe ramming is a trenchless method for installation of steel pipes or casings, in which a pneumatic tool is used to hammer the pipe or the casing into the ground while the excess soil from creating the borehole is removed to the surface. The method is frequently used under railway and road embankments. When casings are installed, pipes of other types for distribution of sewerage, water or gas, or electrical or telecommunication cables are subsequently … |
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American Standards American standards do not cover the process of pipe ramming, but they cover the steel pipes used for ramming. Applicable are standards by the American Society for Testing and Materials (ASTM) and the American Petroleum Institute (API). (Table: American Standards) German Standards (Table: German Standards) |
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The pipe ramming method is non-steerable and pipelines installed by this method are laid straight. In the design phase, it is important to lay the route at a safe distance from existing utilities and other underground objects and protect them from being directly hit or damaged from vibrations. The safe distance required to prevent direct hitting is determined by the installation accuracy of the method, which is, under normal circumstances, expected … |
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Most pipe ramming jobs are designed at depths between 10 and 20 feet below road surface of railway tracks [Yach97a], but can be carried out at shallower depths, between 5 and 10 feet [Yach97b], or even, in extreme cases, at depths less than 18 inches from the surface. Extremely shallow installations should be designed without a soil shoe and, in the construction stage, the surface above the installation line should be monitored carefully to detect … |
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Pipes used for ramming are made from steel. Typically, a new, smooth wall carbon steel pipe that conforms to ASTM Specifications A139, Grade B, should be used. The pipe should have a minimum yield strength of 35,000 psi [Brahl97]. The wall thickness of the pipe should be selected based on calculations to support the maximum anticipated loads on the pipe during the construction and in the operating state. As static thrust calculation used for conventional … |
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Depending on the pipe size and ground conditions, the pipe can be planned to have open or closed end. Open-ended ramming is generally preferable, because it requires less ramming force and is less likely to cause pipe deflection or surface heaving. Closed end is typically reserved for smaller pipes with diameter up to 6 inch [Krame92] or for ground conditions with insufficient self-support, in which the flow of soil into the open pipe could cause … |
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Lubrication with different types of bentonite or polymers is usually essential for the ramming operation. The purpose of lubrication is to reduce the friction between the pipe and the soil. It is recommended in all soil types except in gravels and cobbles, where it is not considered necessary, and in porous sandy soils, where it would dissipate into the soil without accomplishing its purpose. Lubrication is especially important in medium dense to … |
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