Trenchless drainage structure replacement

#Embodiments of the invention relate generally to culvert replacement, and more specifically in one or more of the described embodiments, to trenchless drainage structure replacement.

#Throughout the United States and other countries culverts are failing every day. Culverts provide important drainage functions for roads, railroad beds, and drainage systems. The life of many corrugated metal pipe (CMP) culverts have passed. Just in New Mexico alone over 430 thousand are in critical condition. Culvert failures are imminent and occurring every day. Loss of life, property damage and user delay cost are critical to the public. Using traditional trenched methods the roadway may have to be closed, or in cases where it is feasible to do half width construction, safety concerns come into play, and must be addressed with traffic control solutions which can be problematic in situations of high traffic density as well as locations having limited access through the area of control. Moreover, with increasing environmental regulations trenched methods produce another set of issues because of the amount of material that must be disturbed to replace a culvert Culvert locations by nature are often near bodies of water.

#FIGS. 1-6 are diagrams for a trenchless culvert replacement process according to an embodiment of the invention.

#FIGS. 7 and 8 are diagrams for a collet and tool according to an embodiment of the invention for transferring driving force to a section of replacement pipe.

#FIGS. 9 and 10 are diagrams for a collet according to an embodiment of the invention for transferring driving force to a section of replacement pipe.

#Certain details are set forth below to provide a sufficient understanding of embodiments of the invention. However, it will be clear to one skilled in the art that embodiments of the invention may be practiced without these particular details. Moreover, the particular embodiments of the present invention described herein are provided by way of example and should not be used to limit the scope of the invention to these particular embodiments.

#FIGS. 1 through 6 illustrate a trenchless drainage structure replacement process according to an embodiment of the invention. An example of a drainage structure includes a culvert, for example, culvert 10 shown in FIGS. 1 through 6. Other types of drainage structures or portions of drainage structures (e.g., sewers, storm drains, and the like) having different materials, shapes and designs may be replaced using embodiments of the invention as well. Drainage structures are typically buried and surrounded by earth, and positioned near a road or other structure for vehicles to provide drainage.

#The culvert 10 having an outside cross-sectional dimension (e.g., diameter) of Dold is replaced by driving sections of replacement pipe 20 having a length L and an interior cross-sectional dimension (e.g., diameter) Dnew that is greater than Dold to swallow the culvert 10 (FIG. 1). The culvert 10 may be a corrugated metal pipe (CMP), or may be made from other materials or have other designs. The length L of the sections of replacement pipe 20 may depend at least in part, for example, on the working environment, the material in which the culvert 10 is buried, and the ability to handle and maneuver the sections. The replacement pipe 20 may be a smooth wall A252 grade 3 metal pipe. In some embodiments, the replacement pipe 20 may have designs or may be made from materials other than that shown and specifically identified in the present application. In some embodiments, the chemical composition or the type of metal/alloy of the material from which a metal replacement pipe is formed may be changed based on the chemical composition of the material in which the culvert 10 is buried.