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Shabby Public Realm

W. K. Lis said:
Not just bricks.

Toronto has to use paint on top of asphalt, instead of using coloured asphalt. The paint will wear away over time, in addition they make the surface more slippery.

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Let me just say from personal experience in the asphalt industry, it is very expensive to produce coloured asphalt. It's almost about 5x the cost of standard black asphalt. The additives required are not environmentally friendly, cost of sourcing the colouring addictive and the cost of laying down coloured asphalt comes from designating separate construction vehicles and production plants to maintain a consistent colour without contamination. Then there is the cleaning of production equipment after a project is finished..
 
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Apparently such brick-laying machines aren't all that widely employed in NL, most are laid by hand. The higher material cost is offset by the fact that the pavers last forever and can be relaid following repairs/utility access. I wonder if they would stand up to Canadian levels of salting and freeze/thaw. I suspect our winters would be harder on them than NL would see--though they do get snow.
 
yrt+viva=1system said:
Let me just say from personal experience in the asphalt industry, it is very expensive to produce coloured asphalt. It's almost about 5x the cost of standard black asphalt. The additives required are not environmentally friendly, cost of sourcing the colouring addictive and the cost of laying down coloured asphalt comes from designating separate construction vehicles and production plants to maintain a consistent colour without contamination. Then there is the cleaning of production equipment after a project is finished. *Worked on the asphalt for the VIVA transitways.
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It is used extensively in NL as a top-coat for bike paths. They tend to last a very long time because bikes are essentially like having no traffic at all (inconsequential loading). As I understand it, they use red as it is the cheapest colour to produce. It comes at a premium but it is probably done at sufficient scale that the premium is not so large as to make a dramatic impact on project cost. Unlike a BRT roadway, which I imagine would need to be built to higher load rating and would not last as long.
 
afransen said:
It is used extensively in NL as a top-coat for bike paths. They tend to last a very long time because bikes are essentially like having no traffic at all (inconsequential loading). As I understand it, they use red as it is the cheapest colour to produce. It comes at a premium but it is probably done at sufficient scale that the premium is not so large as to make a dramatic impact on project cost. Unlike a BRT roadway, which I imagine would need to be built to higher load rating and would not last as long.
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That is part of the equation for the cost. Sourcing the material is the predominant driver of the cost. For example red pigmentation is created from adding iron oxide which happens to be only readily available from Germany. So the cost of transporting the material is much less to the Netherlands from Germany than to Canada (the VIVA project had to ship a lot of the red stuff from Germany for part of the project).

This is of course depends on what method you want to make your coloured asphalt:

eg. start with black asphalt > make it white > then pigmentation for the required colour
eg. create clear asphalt > add pigmentation
 
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afransen said:
I suspect our winters would be harder on them than NL would see--though they do get snow.
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They get snow but it rarely goes below zero long enough for the ground to freeze.

That said, Toronto has lots of brickwork (on the waterfront) that survives winter perfectly well. A thick concrete layer with brick/sand on top seems to work well here. The thick concrete layer doesn't make utility cuts any easier but the brick would hide the repair.
 
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Toronto has had brick roads for over a century, and some of the original bits from that time are still in tact.

Notably in Forest Hill.

But also down in the Old Mill area as well.

Done properly these can be made to last.
 
Northern Light said:
Toronto has had brick roads for over a century, and some of the original bits from that time are still in tact.
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Interesting. I was only aware of May St. in Rosedale which is so rough it's actually difficult to walk down at night. May St. also has the vertical sewers (hole in the curb type design) that people here like too; which plug with snow quite very easily.
 
yrt+viva=1system said:
That is part of the equation for the cost. Sourcing the material is the predominant driver of the cost. For example red pigmentation is created from adding iron oxide which happens to be only readily available from Germany. So the cost of transporting the material is much less to the Netherlands from Germany than to Canada (the VIVA project had to ship a lot of the red stuff from Germany for part of the project).

This is of course depending on what method you want to make your coloured asphalt:

eg. start with black asphalt > make it white > then pigmentation for the required colour
eg. create clear asphalt > add pigmentation
Click to expand...

How does it work when it comes time to scrape up and recycle coloured asphalt? My understanding is that it's a very heavily recycled item. Does colour cause it to have to be separated, or worse, discarded?
 
As I mentioned in this thread before I find from experience that interlock (brick or concrete pavers) hold ice much more than concrete. A minor detail but basically unless you salt the crap out of it, interlock and brick are liabilities in the frozen months. At this point I would personally never chose interlock or brick as a path pavement treatment for a rental property.
 
Northern Light said:
Toronto has had brick roads for over a century, and some of the original bits from that time are still in tact.

Notably in Forest Hill.

But also down in the Old Mill area as well.

Done properly these can be made to last.
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There's Chiltern Hill Road in Cedarvale that even has the brick roadbed exposed in some sections.
 
Permeable concrete has been used in some small Minnesota towns to great effect, including in winter.

nextcity.org

How a Twin Cities Suburb Has Led The Way With Permeable Pavement

The new type of road lets cities avoid using salt in winter.
nextcity.org

There are lots of interesting options out there.

I'll add there is a version of this with interlocking pavers as well.

This is not suited to roads with high volumes of traffic or lots of heavy trucks.

Permeable pavement (asphalt, concrete, or pavers)

Permeable pavements are designed to allow percolation or infiltration of storm water through the pavement surface.
www.dnr.state.mn.us www.dnr.state.mn.us
 
vic said:
How does it work when it comes time to scrape up and recycle coloured asphalt? My understanding is that it's a very heavily recycled item. Does colour cause it to have to be separated, or worse, discarded?
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I don't see why it couldn't be blended with other recycled asphalt. You might see the odd bit of colour but it would be almost completely coated.
 
vic said:
How does it work when it comes time to scrape up and recycle coloured asphalt? My understanding is that it's a very heavily recycled item. Does colour cause it to have to be separated, or worse, discarded?
Click to expand...
In the industry recycled asphalt or what is ripped up is called recycled asphalt pavement (RAP). There actually isn't much coloured RAP since it's seldom laid down but if it's ripped up it is usually dumped into a separate RAP pile. Mind you most coloured asphalt is used for parking lots or pathways and the red-pinkish colour of say some roads are usually due to the aggregate used (eg. granite from northern Ontario).
Most newly repaved roads in the province only contain about 3-5% RAP and this specification is determined by the customer; eg. MTO mandates 3% RAP for all the 400 series highways. The problem with using RAP and the reason why one usually sees gargantuan mountains of old asphalt on asphalt plant yards is that it's very difficult to use. RAP can contain huge variations of materials and different grades of asphalt concrete (the actual black tar like substance is called asphalt or asphalt concrete, what is laid down on a road way is known as hot mix). Then there is the question of how old is the RAP and the exposure to weathering since it does sit outdoors, over time asphalt concrete washes off (its not a solid). Touching back on the question of materials used on old roadways, some roads like the ones in cities may contain asbestos. To make it even more challenging is the fact that some roads paved in the last 10 years have been using materials such as recycled tire particles, old motor oil collected from the automobile industry and crude vegetable oil. Mainly to cut cost but also being mandated to make roads more environmentally friendly. These roads don't have the durability of older roads. So to sort of answer your question, old coloured asphalt might be used but more often it is condemned to a pile at the very back corner of a yard. Over the span of almost 10 years, I've only had to deal with coloured asphalt hot mix on two occasions; one being the time I was making sample colour asphalt pucks for customers (various shades of white, red, green and blue) and two being the VIVA busway.

Fun fact, RAP in the lower levels of stratification can look identical and smell like fresh triple mix garden soil.
 
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I'm sure there are a number of interesting engineering and material solutions. As someone trained as an engineer I'd love to employ a technical solution. I know at the municipal level they talk about it all the time, then the legal team advises and everyone just goes back to dumping crap loads of salt on things. You can only be sued so many times before you just give up on that file. You would have to reform the legal system to see technical solutions widely adopted. I tell guys all the time to go easy on the salt but then why bother? I'm actually opening myself up to liability simply for suggesting it. How about capping injury payout for slip-fall accidents to $1000 max ;)
 
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