It is possible to salvage failing structures and eliminate the expense of lost time, the inconvenience of road closures, the loss of hydraulic capacity and cost of overcoming safety problems connected with complement replacement.
CSP systems have been employed for almost a century in rehabilitation projects, providing a cost savings and reducing the disruption caused by the removal of old structures. Lining inadequate or failing structures with CSP systems uses little of the available space within the structure.
This preserves the maximum amount of the original opening. CSP’s hydraulically efficient linings and corrugation profiles allow a smaller structure to provide the same hydraulic capacity as the existing structure.
Variety of Shapes and Sizes
Existing pipes and arches are generally lined with structures of the same shape, though of a slightly smaller size. Rectangular openings can be lined with round, elliptical or pipe-arch structures. CSP sizes are not limited by forms or mandrels and can be fabricated to fit most any size opening.
Backfilling
Grout is placed in the annular space between the existing and liner pipes. This grout minimizes further deterioration of the existing pipe and reduces concentrated loads on the liner pipe. Fill materials can be sand, sand-cement mix, grout, flowable fill or concrete. The liner pipe can be fabricated with hardware to facilitate alignment of the pipe and grouting of the annular space.
Rehabilitating Bridges and Large Culverts
Bridges and large culverts can be relined by assembling corrugated steel plate structures inside the existing structure, or the new plate lining can be assembled outside and slide into the existing opening. The plates are easily bolted together on-site to form any of the required shapes: round, vertical and horizontal ellipses, pipe-arch, underpass and arch.