After hardening of the deck slab, an overlay of 25 mm (1 in.)
concrete grout was introduced over the concrete deck slab
edge with a width equal to the barrier width. Barrier segments
were then laid over the deck slab edges, with the centerlines
of the sleeves aligned so that 25 mm diameter threaded steel
rods could be inserted. The threaded rods were then bolted
from the top of the barrier wall and at the bottom of the deck.
A torque was applied to the top nuts to provide an initial tension
in the threaded rod and compressive stress at the contact
surface between the barrier wall and the slab. This limits water
leakage onto traffic under the bridge.
To increase shear resistance, the top surface of the concrete
deck slab was scratched parallel to the direction of traffic.
For a similar surface on the bottom of the precast concrete
barrier wall, timber strips can be nailed inside the form
(Fig. 2). After tensioning the threaded rods to the desired
level, concrete grout was inserted from a hole in the top
steel plate on the side of the top nut (detail A in Fig. 2)