Thanks for the photos. It
looks like the glare screen had minimal reinforcement, leaving it susceptible to
heavy damage. A monolithic pour for the barrier and glare screen would have
likely helped. Utilizing full-height transverse steel stirrups would be
even better. I would not expect to see anywhere near this level of damage
to Manitoba bridge rail or the 56” tall TL-5 barrier in SCDOT’s standards.
Yes, the glare shield is a poor design. It was doweled into
the top of the jersey barrier and contained 3 #3 bars horizontally.
Have you seen a glare shield retrofit for Jersey barriers that is
more durable? This would be helpful if we need to install new glare
shield in locations where existing barrier is Jersey barrier.
The Jersey barrier was 12" thick at the top, 24" thick at
the base, and in the impact shown in the attached image, the damage goes all
the way to the ground.
We have also seen instances with damage to the upper portion of
the Jersey that goes down to the bottom slope. Some of those cases again
might have had 3 rows of #2 bars in that upper portion.
We agree that the new reinforcing will virtually eliminate this
issue, but see that some states are detailing the barriers without reinforcing.
One major complaint from contractors is that the rebar is greatly
affecting the slipforming process. One asked about removing it entirely,
another asked to remove just the vertical bars. Caltrans indicates the
vertical bars just at the expansion joints/ends of the wall, and contractors
are trying to submit other state or tested details as alternates to our
details. Ultimately, our first project was built with rebar cages
consistent with our standards, but the contractor did have some issues when the
cage was not sufficiently secured before the slipforming operation. In
the Caltrans details, the vertical barriers are flipped from our details.
Do you know if they have had any construction issues with their rebar or
We had an internal meeting last week to address some of the
construction concerns that the contractors have raised, and likely will
increase our barrier width by 4" (10" wide at top, 28" at
bottom). This hopefully will allow the rebar cage to fit better in the
barrier. The current main concern from the contractor was to use 4000 psi
concrete, which will be allowed moving forward.