Tie Bar Placement

Tie bars are typically placed after PCC placement either by hand or using a tie bar inserter attachment (slipform paving only). When one lane at a time is paved, tie bars are inserted at mid-slab depth and bent back until the adjacent lane is ready to be paved (see Figure 1). On slipform pavers, tie bars are inserted on slab edges that will become longitudinal joints (see Figure 2 and 3) and, if two lanes at once are being paved, pushed into a mid-slab area (similar to dowel bar insertion) that will later be cut as a longitudinal joint (see Figure 4 and 5). Like dowel bars, tie bars should be protected from corrosion.

Bent tie bars.
Figure 1. Bent tie bars.

Side tie bar inserter.
Figure 2. Side tie bar inserter.
Tie bar insertion equipment for side tie bars.
Figure 3. Tie bar insertion equipment for side tie bars.

Inserter for mid-slab tie bars (the area in which the tie bars are inserted will later be cut as a longitudinal joint).
Figure 4. Inserter for mid-slab tie bars (the area in which the tie bars are inserted will later be cut as a longitudinal joint).

Tie bar insertion cartridge protruding upward from the center of a slipform paver.
Figure 5. Tie bar insertion cartridge protruding upward from the center of a slipform paver.