To install curved formwork, use 12mm plywood with 50 x 50mm hardwood pegs spaced 500mm apart. Secure the formwork to the pegs using 40mm bullethead nails. Brace the pegs with a kicker, if the formwork extends more than 150mm above the ground.
Use a plate compactor to pack the ground, lay 100mm of roadbase material, then pack again. Spread a 20mm layer of sand to eliminate friction between the concrete and base.
TIP Large plate compactors can be hired for about $60 per day.
Fill the formwork with concrete and spread it evenly using a rake or shovel. Lift the steel mesh off the ground to centre it in the concrete, then tap the sides with a hammer to eliminate trapped air pockets. Pack concrete along the edges with a float.
Use a timber screed to level the concrete with a sawing action. Smooth the surface with a hand float in both directions to bring the cement cream to the top for a smooth surface.
TIP Use a steel float for a smooth finish or timber for a slip-free, rougher result.
Use a straightedge and a concrete groover to cut control joints in the surface of the concrete at intervals equal to the path’s width. Cracks that occur as the concrete dries will form along the joints. Drag a stiff-bristled broom over to hide any imperfections.
Once the concrete is hard enough that your finger doesn’t leave an indent, cover with plastic sheeting and weight down. Keep it damp for three days, sprinkling water over areas that dry too fast. Let it harden for a further two days, then remove the formwork.