if we're seeing this in the summertime, it's pretty much guaranteed that you'll see it in the wintertime which means it's not a maintenance issue. there is no way you will heat and hoard and close down traffic lanes to repair this kind of damage in the winter which means it will sit unrepaired for months deteriorating even more.
you're not going to repair this by crazy-gluing those chunks of concrete back in place the morning after, you're going to sawcut out enough of the wall to drill new rebar into undamaged sections, remove enough earth and planting to form the new wall sections, install your rebar and pour the concrete and come back a week later after it's cured to strip the forms and backfill and re-landscape...
in this case i think it is primarily a poor design issue more than a poor material choice (i.e. it likely needs to be an 8" or thicker wall with more than one piece of nominal rebar at the top) while lane width and curb design should minimize this type of event rather than contribute to it. there's nothing wrong with attractive and elegant but it still needs to be heavy duty enough to continue to look attractive and elegant through normal use and exposure. if this is what it immediately looks like as a result of readily anticipated events, that's a failure.