Crack pattern and failure modes
Barrier model M1 emulated the precast concrete barrier
wall with its pretensioned connection with the deck slab
to study the resistance of the joint between the barrier and
the deck slab. At a load of 60 kN (13 kip), the first crack
was observed at the front of the barrier wall between the
bottom surface of the barrier and top surface of the cement
grout (Fig. 11). The front of the barrier was the side with
tapered faces. With increasing load, a major horizontal
crack developed approximately at the middepth of the deck
slab on the left side of the barrier wall (Fig. 11), leading to
an anchorage failure under the barrier wall. This anchorage
failure was also exhibited on the right side of the barrier
wall (Fig. 11) but associated with a combined flexureshear-bond
crack pattern. The anchorage crack extended
into the slab away from the front side of the barrier wall in
a combined flexure-shear-bond crack pattern. The specimen
failed mainly due to anchorage failure in the deck slab
at 174.61 kN (39.256 kip). The test was terminated when
the specimen could not absorb additional load.
Barrier model M2 had similar geometry to model M1 but
was considered a control specimen because it represented
the monolithic cast-in-place concrete barrier wall system.
At a load of 70 kN (16 kip), the first concrete crack was