January 25, 2007
The bricks rated coverage in Today's O.
Original Post: 1/15/07
A few months back, at the intersection of 6th & Taylor, TriMet installed some new sand-set pavers as a test for potentially using them in the Transit Mall reconstruction. A reader recently queried me on whether I knew how the test was going, and I forwarded the question on to TriMet. Here's the response:
The installation at 6th & Taylor, as expected, has been doing very well. This 'mock-up' of the brick paver system was installed this past July so that bus and other traffic could interact with the system over time and through a variety of weather conditions.
Over this period we've had the opportunity to test how the design held up to heavy axle loading by buses, impacts to the system's stability by underground utility work, and ability to affect repairs and maintenance within a functioning transit street. Additionally, the design has been evaluated by a host of public entities during this testing period.
While the brick paver system has performed admirably, we've already determined several modest adjustments that respond to recommendations for improving pedestrian movements, and to facilitate the actual construction of the Mall's brick intersections. Working with the manufacturer the brick paver will reduce 'bumpiness' by using a tighter paver joint and reducing the paver's edge chamfer.
Additionally, the slip-resistance of the pavers has been verified by an independent testing agency and exceeds the City's and Federal recommendations. Another mock-up of the intersection's pixilated circle led to using a third colored paver for improved visual clarity.
The mocked-up intersection will continued to be monitored until the actual Mall construction, but its clear that the new system will be much safer for all users of the Mall, more durable, easier to maintain, and aesthetically pleasing urban design treatment. The project intends to install this new system in the Central Mall, on 6th & 5th Avenues, south of Burnside to Market Street.
January 8, 2007 12:01 AM
Alan Locklear Says:
What happens when one of these pavers is removed (broken or pried up)? Doesn't the integrity of this kind of pavement depend upon all the pavers being intact and in place? It's clear from the condition of a lot of paving blocks on the transit mall, that years of constant pounding by buses and other vehicles will break very heavy-duty materials. Will the city and/or Trimet have a crew working its way up and down the mall on a daily basis looking for and replacing broken pavers before they are bounced out of place by traffic or pried up by vandals?
January 8, 2007 10:32 AM
Bob R. Says:
pried up by vandals
This very point came up at a CAC meeting.
The response was that the old mortar-set system was so vulnerably to decay and so hard to maintain that today you can have any brick you want.
Sandset pavers are heavier and more durable and actually harder to just reach in and remove than a failing mortar-set brick.
But to be sure that the system would work, the testbed was put in place months ago. This is not a new system, it has been used in Europe for centuries, and in Seattle for several years (although Seattle's initial implementation failed until experts from Europe showed them how to do it right).
The mantra about operating funds for the transit mall has been: Long-term maintenance costs - long-term maintenance costs. Sandset pavers are more expensive to put in, but much easier to maintain without degradation in the long term.
Personally, I will miss the signature circular granite motif in the middle of each intersection, but I fully understand how quickly the current intersection treatments wear down.
- Bob R.
January 26, 2007 8:06 PM
Jason McHuff Says:
Thanks for posting the link. I would have noticed the article but the O has been re-designing their site and, while the new design is nice, there appears to no longer be a way to get a list of all articles, such as the one linked, on one page.
Also, regarding the circles, lets hope that adding more colored bricks will make it look like a circle. With just one (different) color, the test did not look like a one.