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Pipe bursting and related techniques are well-established methods for trenchless replacement of worn out and undersized gas, water or sewer pipelines. They can offer significant potential savings and drastically reduced surface disruption to public and private utility owners under favorable conditions. The methods result in an existing pipe being replaced size-for-size or up-sized with a new pipe in the same location. The techniques are most advantageous … |
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The process of pipe bursting is currently not covered by ASTM Standards. Only the plastic pipes, which are used as replacement pipes, are covered. (Unless otherwise noted, all ASTM Standards should be for the latest year of publication.) (Table: American Society for Testing and Materials (ASTM) Standards - Overview) |
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Standards for Plastic Piping, September, 1990. |
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Standard No. 14 - Plastics Piping System Components and Related Materials, 1988. |
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Atalah, A. (1998). The Effect of Pipe Bursting on Nearby Utilities, Pavement and Structures, Technical Report No. TTC-98-01, Trenchless Technology Center, Louisiana Tech University, Ruston, LA. |
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Many other reports and technical papers are available that describe the various pipe bursting techniques, report case histories and describe field and laboratory experimentation on the effects of pipe bursting. These papers are listed in the bibliography at the end of these guidelines. Only specific references are listed below. Fraser, R., N. Howell and R. Torielli, 1992. "Pipe Bursting: The Pipeline Insertion Method," Proceedings of No-Dig International '… |
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The most favorable ground conditions for pipe bursting projects are where the ground surrounding the pipe can be compacted readily by the bursting operation as it is displaced. This will limit the outward ground displacements to a zone close to the pipe alignment. It is also favorable if the soil surrounding the pipe will allow the expanded hole to remain open while the replacement pipe is being installed. This will lower the drag on the replacement … |
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Pipe bursting below the groundwater table increases the difficulty of bursting operations. Bursting in saturated soil can cause the water pressure to rise around the bursting head, unless the soil has a high enough permeability to allow the water pressure to dissipate quickly. The rise in water pressure causes the effective stress in the soil to drop and may cause the soil to behave more like a viscous fluid. When the fluidized soil displaces the … |
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Most brittle pipe materials make good candidates for pipe bursting. Ductile pipes may be scored and then slit as in the pipe splitting operations described above. Pipes made of non-ductile abrasive material but with ductile reinforcing are the most difficult to replace using most pipe replacement techniques. Common types of pipe and their bursting characteristics are indicated below:
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In the smaller size ranges, a small diameter pipe may be harder to burst than a larger size pipe, because the walls are thicker in relation to the size of tool. It is considered that an 8-inch pipe is easier to burst than a 4-inch pipe. The host pipe diameter and the required upsize of the new pipe determine machine selection. To date, upsizing by up to 30% of the original pipe diameter is common, and greater upsizing has been successfully completed … |
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The depth of the host pipe affects the expansion of surrounding soil. Also, water table considerations vary with depth. Insertion and reception pits grow larger and more complex as the depth increases. The existing profile of the bursting run can also affect the planning and execution of the pipe bursting operation, especially changes in grade or bends. If pre-installation video inspection reveals a sag in the existing sewer line larger than acceptable (… |
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Surrounding utilities can affect the location of insertion and reception pits. Utilities that interfere with or may be damaged by the burst should be located and exposed prior to the burst. For typical pipe bursting operations, underground utilities in moderate condition are unlikely to be damaged by vibrations at distances of greater than 2.5 feet from the bursting head [Atala98a] [Atala98b] [Atala98c] and ground displacements are unlikely to cause … |
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While not common in all jurisdictions, occasionally pipe bursting takes place through horizontal or vertical curves. Although many long bursts through relatively short radius curves have been successful using both static (rod) and pneumatic systems, careful consideration of methodology is required. It is prudent to plan for the space and excavation requirements of a pit at the midpoint of a run, such as at the apex of a curve. The repair history of … |
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HDPE and MDPE are the most common new pipe materials. The main advantages of PE pipe are its continuity, flexibility, and versatility. The continuity is obtained by hot fusing long segments together in the field prior to insertion. The continuity during the installation reduces the likelihood of needing to interrupt the bursting process. The flexibility allows bending of the pipe for angled insertion in the field. In addition, PE is a versatile material … |
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The location of insertion and access pits should be such that their number is minimized and the length of bursting maximized consistent with the equipment available for the burst and the expected stress on the replacement pipe. In sewer replacement jobs, the burst length is usually from manhole to manhole. An intermediate manhole can be passed through with proper preparation. Longer than normal bursts may need larger tools and lubrication mud to reduce … |
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In water main replacement, an internal protective sleeve may be used to protect the interior of the water main from contamination from dirt, oil, exhaust gas, etc. caused by equipment and hoses that must be installed in the replacement pipe for the bursting operation to function. The static pull method does not require hoses or equipment in the replacement pipe if a continuous replacement pipe is used and hence, for this condition, does not require … |
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The effect of pipe bursting on nearby structures and adjacent pipes needs to be carefully analyzed. The design of a pipe bursting job has to assure admissible soil displacements and, if necessary, to include damage prevention measures (local excavations made to relieve induced stresses). Laboratory studies, field studies, analytical and simulation techniques have been used to predict the soil displacements along the pipe adjacent to the pipe being … |
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Design considerations evolve from ground conditions, groundwater conditions, degree of upsizing required, construction and depth of the existing pipeline, etc. This chapter discusses these issues and their relevance, and gives some general guidance about the selection of replacement pipe, bursting length, necessity for the use of a sleeve pipe, etc. |
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Service connections (sewer, gas and water) to the pipeline being burst can create problems during bursting regardless of whether they are excavated prior to bursting or not. The services are usually excavated prior to bursting to provide temporary bypass service and to protect the services during the bursting operation. If the connections are not excavated prior to bursting, they can easily be damaged and the damage to the service lateral may happen … |
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For sewer applications insertion and reception pits are usually excavated in front of manholes, or manholes are removed and replaced. For replacement of gas and water lines, service pits can be expanded and used for the insertion and reception pit. All pits should be prepared and shored in an approved manner. For all static rod and cable pull machines, the machine should be properly braced to resist the horizontal force necessary for the bursting … |
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When a replacement pipe is of polyethylene, it is delivered onto the site in segments and butt-fused into a continuous pipe on site. The maximum length to be installed is limited by the space available for the pipe to be assembled prior to bursting and by the maximum tension expected in the pipe during the pull in operation. Fusion is carried out prior to the bursting operation, so that all fused joints can be checked and there is no delay due to … |
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