Subgrade Guided Towed Boat Liner
For small canals, a low cost and practical concrete lining option is a G&Z Subgrade Guided Towed Boat Liner. Because the liner follows the precisely excavated canal cross-section created by a trapezoidal trencher, it maintains accurate grade and alignment while keeping concrete losses to an absolute minimum. The Liner subgrade guide and canal mold can be provided with attachments to accommodate different canal bottom widths and lining thicknesses.
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Capabilities:
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Smaller Towed Boat Liner: Up to approx. 48” (1.22 m) deep with slopes of 1:1, 1.25:1, or 1.5:1 and bottom widths from 12” to 48” (0.3–1.22 m).
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Larger Towed Boat Liners: Up to approx. 7 ft (2.13 m) deep with slopes of 1:1, 1.25:1, or 1.5:1 and bottom widths from 40” to 60” (1–1.5 m).
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Smaller towed boat liners can be towed by a front-end loader, G&Z TL6300 or TL7300 Tugger which can also place and remove the liner from the canal. A motor grader can also be used to tow the liner. Higher-slump concrete is typically used, so vibration is not required (optional vibrator units are available as an option. Concrete can usually be discharged directly from transit / truck mixers into the liner hopper. For small canals with wider top widths, a concrete auger or shuttle conveyor can be mounted in the hopper to ensure concrete delivery to slope opposite the concrete feed side. If space is limited on the berm next to the canal, an optional charging conveyor can elevate and feed the concrete from the concrete haul road to the liner hopper.
Larger towed boat liners can be equipped with a diesel engine powered hydraulic pumping unit to run the towing winch, concrete distribution system, and optional vibrators. When using a winch, a “Deadman” (tractor or loader) provides the anchor point ahead of the liner. A crane truck or even a large excavator can be used to place and remove the liner from the canal.
An access platform at the rear of the canal mold provides access for finishing — with the option to add a transverse joint cutter (“Guillotine”). Handheld transverse joint cutters can also be provided for smaller canal cross section. For larger canal cross sections, a separate, self-propelled, WB7300 work bridge for finishing and curing the concrete lining is available.
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A crane truck is required to place and remove the liner from the canal. For maximum efficiency, G&Z’s TL6300 or TL7300 Tugger—a crawler track machine that straddles the top of the canal —can tow, lift, and transport the liner around obstacles while supplying power to its systems. With the larger Liners, due to the larger canal cross section, a separate, self-propelled, WB7300 work bridge for finishing and curing the concrete lining is available.
