Archive for the ‘Technical’ Category

the critical role of spiders in building Vaughan Metropolitan Centre Station

Wednesday, January 10th, 2018

Now, before you think we’ve imported some exotic tropical arachnids, what we call “spiders” are actually the stainless steel fittings that hold together the glass pieces on our stations. They’re called spiders due to their shape, and they play a critical role in the architectural and structural design of our stations.

For the new Vaughan Metropolitan Centre [VMC] rapidway station, the main structural support comes from the welded steel superstructure that forms the distinctive curved shape. Over top of that, steel, custom-made spider fittings are bolted to each steel intersection. The spider fittings support the individual glass panels on the station’s sides and skylight.

410 panels of glass

Each triangular-shaped panel of glass is attached by brackets on the legs of the spiders. Because each piece of glass is a unique size and shape, the job of attaching the glass to the spiders is very fiddly. The extra-large 50 by 24 metre VMC canopy has an eye-popping 410 panels, each equally spaced and slightly different due to the station’s curved planes. The tempered glass can’t be cut or drilled on site without shattering, so holes for the brackets were made during the fabrication process.

beautiful precision

We knew if the holes in the glass didn’t line up exactly to the spider brackets, the glass pieces wouldn’t fit. Since glass fabrication is a fairly slow process, we didn’t want to risk having to go back and remake a piece. Rather than making the glass in advance, we installed the spiders, then measured them with a 3-D laser scanner that registered the targets as multiple cloud points; essentially the same process used to make a 3-D model.

The last step was the installation of the glass panels to the station roof, and seeing all this precision and planning come together for beautiful results. Now if you visit the VMC rapidway station, you can take shelter under a strong and stunning glass canopy reminiscent of the great European architectural traditions, right here in York Region.

 

beautiful curves of glass

Wednesday, December 27th, 2017

If you’ve ever had to replace a window in your house, you know that working with glass is fiddly, exacting work. It needs to fit perfectly or you’ll get drafts and leaks. Glass has no tolerance for being the wrong shape or size. And dropping a pane from a window: well, that means another trip back to the store.

Now, imagine the challenges of installing the glass on the curves of our new Vaughan Metropolitan Centre [VMC] rapidway station. As you can guess, it was a long, multi-stage process, done with great care and precision.

strength and safety

As with all our vivastations, the VMC glass was laminated and tempered for strength and safety. First the glass was cut into panes, and then it went through a special process to make it extra strong. This way, if it breaks, it crumbles into small granular chunks instead of sharp pieces.

To add more strength and make it even safer, we then laminated the tempered glass by sandwiching two glass sheets together around an interlayer. If the glass is broken, the interlayer holds the small pieces together instead of breaking into many little shards, the same way a car windshield stays together in an accident. The interlayer on the blue skylight glass is actually a different, stronger material than the interlayer used for the clear side glass, since the top skylight needs to support heavier loads from snow and maintenance workers.

creating curves

Fitting flat glass to the curved shape of the station was a challenge, because every surface of the steel roof curved over two dimensions, much like the outside of a ball. The first step was to divide the glass into a series of triangles. Three-sided shapes are easier to work with compared to four-sided shapes, the same way a tripod is more stable on uneven ground compared to a four-legged chair.

But this still left the challenge of fitting flat pieces of glass over a curved frame. The solution here was to adjust the bolts on the corners of the spiders [the stainless steel fittings that hold  the glass pieces onto the frame] so they’re each set at a different height. We knew how high each bolt needed to be from 3D scans, so we adjusted them before we installed the glass. By installing each corner of glass at a slightly different height, we recreated the curves of the tubular steel frame.

intricate jigsaw puzzle

The last step was putting the glass panels in place, one by one. Although they were all triangles, every piece was unique like pieces of a jigsaw puzzle, so to avoid mix-ups they were carefully numbered before they were delivered. Once the glass panels were bolted onto the spiders and the final adjustments made to perfect the curve of the glass, we sealed the gaps with caulking to make the structure weather-tight.

Building this strong and beautiful glass-covered station took precision, but look at the stunning results! This landmark station helps set the architectural stage for future development at the VMC and makes the everyday experience of transit a beautiful one for our customers.

proof of performance

Wednesday, December 13th, 2017

The days are counting down and the excitement is growing. The launch of our extraordinary new vivastation at Vaughan Metropolitan Centre, along with the ground-breaking TTC Line 1 subway extension and our rapidway, is only four days away. Now we have one last crucial task to complete before our gorgeous new station joins the transit mega-hub at the VMC: we need to carry out commissioning.

testing, one, two, three

Commissioning of the new bus rapid transit station is similar to the process we do for all our new stations, rapidways and facilities. Very simply, it means confirming everything we installed, from the heaters and automatic doors in the passenger enclosures, to the cameras, speakers and variable message signs [VMS] on the platforms, works the way it’s supposed to.

Before their work is done, our builders have to test every single device and piece of equipment to demonstrate they met all their obligations. The station has complex equipment for fares and security, and all the general building components like lights, plumbing, and electrical connections. Systems connect to the central York Region control room, enabling them to see the platforms, hear the speakers, run messages on the VMS and communicate through emergency call buttons. During commissioning, every light switch, outlet and connection is tested. Our builder also works with the new station owners, YRT/Viva, to help them assume operation.

smart systems

The new station is part of a highly sophisticated system which includes the broader rapidway network and its whole range of intelligent transportation system [ITS] features. ITS is really the reason Viva is able to operate as a rapid transit service, keeping our system running on time with supervision from YRT/Viva’s central control room.

trial run

A critical part of commissioning is testing the newly finished components in the new VMC station and the surrounding rapidway, to make sure they’re all connected properly to the control room and the rest of the system. Testing for full integration requires that we run buses through the new rapidway for a day. During that process, we’ll make sure that all the traffic-related components are communicating properly to the buses and to the general system, and ensure the traffic signal timing is set for optimal travel times.

This station has one more layer of complexity beyond the other stations we’ve built, because of its connections to the TTC. We need to check every interface with the TTC system, which includes electrical connections running between our station and their panels below.

Commissioning is the final step, and you can see why it’s so important to do it carefully and methodically. Because of that complexity, some work will continue on the station in 2018. But once it’s finished, get ready to celebrate and enjoy faster transit with us!

collaboration now and for the future

Friday, December 8th, 2017

Building our Vaughan Metropolitan Centre rapidway station required close collaboration with the TTC, since it’s so near to their new subway station – literally on top of it, in fact! The collaboration began at the design stage, and continued between our two construction teams as we brought the plans to life.

staging for success

With the new rapidway station being built in layers, and in the middle of the road, staging was crucial for both the vivaNext team and TTC. Staging means carrying out work in phases, such as shifting traffic lanes from side to side to give crews room to work safely. Another example was how we stayed clear of the TTC work crews while they finished the subway box, before we started on the concrete and rebar that went on top.

teamwork

Coordinating with the TTC, vivaNext crews shifted the traffic to one side while we built the road on the other side, and they worked on that side of the underground subway structure. Then, when we flipped the traffic back to widen the other side, the TTC also switched sides. A detailed planning process ensured we both did what we needed to do, in the right order and the shortest possible time, without tripping over each other.

Building the escalators and elevators from the TTC station to the BRT station also took detailed planning and coordination. Rules and specifications determine how closely crews can work to adjoining crews. The subway and rapidway stations share a very small area. If you’ve ever done a renovation, this was like having one group building the stairs, and another building the walls and hanging the wallpaper.

the collaboration continues

Most of that coordination is done now, with the vivastation area fully under our contractor’s control. We’ll continue to work closely with the TTC as we get to the final stages of signoff for the station equipment. On opening day, December 17, there may be some finishing touches still required, but we will open for service!

The collaboration continues even after the work is done, since the goal of the new station is to create seamless connections between Viva rapid transit and the TTC. We’re looking forward to a long, happy future of working together to get you where you want to be.

the crowning touch

Wednesday, December 6th, 2017

Ready for the crowning touch? The new SmartCentres Place Bus Terminal comes with a mesmerizing pièce de résistance – a sweeping, curved wooden roof, as beautiful as it is functional.

Reminiscent of West Coast style, the horseshoe-shaped roof shelters the outdoor bus stations in beautiful elegance. A fluidity breathes life into the design, curving in a slight v-shape from the outside in, and rising up at the wingtips and the saddle. You can almost feel the motion, very fitting for a bus terminal with YRT/Viva services branching out across York Region.

an intricate jigsaw puzzle

The simple elegance of the roof belies the complexity of its creation. The wood pieces need to look curved, but they are flat. Custom-cut to the architect’s design, they fit together with the steel substructure, which was also designed in custom pieces.

It’s like a very complicated jigsaw puzzle. Every section is numbered and assembled with exact precision. When the flat pieces fit together, they create the appearance of a curved roof. High-strength glued-laminated timber beams support the roof, running vertically and also lengthwise.

Not only does the wood look stunning, it was a cost-effective choice and is Forest Stewardship Council (FSC) certified to York Region standards. When it’s finished, it will be stain-coated with intumescent fire-retardant material.

 a showstopper for a new downtown

The result is an eye-catching landmark – a roof that draws the eye and a terminal where you can pass the time in style. After all, SmartCentres Place Bus Terminal is not your run-of-the-mill bus station. As part of the vibrant, new downtown flourishing at Vaughan Metropolitan Centre, this bus station needs to look the part.

Set to open in 2018, the Terminal will complete the transit powerhouse at the VMC: subway, rapidway and YRT/Viva terminal, working together to move you, faster and easier than ever before.

the concrete choice

Monday, December 4th, 2017

If you’ve ever renovated your home, you know about the endless options for flooring: tile, wood, carpet, stone. Once you select your material, you have to make more choices about colour, finish, how it should be arranged, even the kind and colour of grout. So many decisions! Of course, as with all design questions, your choices are shaped first and foremost by the space and its function: wet or dry? Formal or casual? How much wear will it get?

the floor dilemma

Our design teams faced similar quandaries when working out the details for the rapidway platform floor of the new Vaughan Metropolitan Centre Station [Viva bus rapid transit].

All of our other open air vivastations have tiled platform floors, so the obvious choice would be to use that in the new VMC Station. But this station faced an additional level of complexity, being built above the subway extension.

The top of the subway station extends to just under the vivastation foundation, providing limited depth to work with. Installing the tiles with concrete underneath as required would use up space needed for essential power and communications cables. A concrete floor became the ideal alternative.

durable by nature

Concrete flooring for the platform works better in the space we have, and the durability means less maintenance is required, saving money down the road. The VMC Station floor will be getting a lot of use in a relatively small space. We know concrete will perform.

But, we also want great aesthetics. Fortunately, concrete is also versatile.

Outside the station along the sidewalks of Highway 7 are paver stones laid in a distinctive pattern. Inside the station, we’re re-creating that look with concrete. First, we built the concrete molds to match the sidewalk, then poured each section with matching colours of concrete.

functions like concrete, looks like tile

Because the platform floor continues beyond the shelter of the vivastation canopy, we needed to ensure it’s not slippery. Before the concrete set, every concrete slab was given a hand-applied swirl finish to provide a measure of slip-resistance. We have also done decorative work on each section to create the appearance of tile.

Just like you’d want for your own home, the final result will meet design goals in every way: strong, durable, easy-to-maintain, and functional. And nice to look at, too.

 

taming the wind

Friday, November 24th, 2017

One of the design considerations behind the new rapidway station at Vaughan Metropolitan Centre are the heavy traffic volumes on that stretch of Highway 7. It’s a busy area, and with all the exciting new development coming to the VMC, it’s only getting busier.

As we’ve talked about here, making people feel safe and secure while they wait in the vivastation in the middle of Highway 7 is one of our top priorities. But beyond providing a physically safe waiting place, we also want to provide a comfortable experience for transit users. So the new vivastation offers lots of options, whether people want to wait inside the glass enclosures, on the platform under the high roof, or on the outside platforms.

fresh air, no wind!

For those who prefer being out in the fresh air while they await their YRT/Viva bus, there will be planters of greenery and trees to enjoy, but with all that traffic whizzing by, some might have found it a bit blustery. That’s why we’ve installed special windscreens, on the north platform where the traffic comes closest.

windscreens as art

The seven windscreens are located just to the west of the station on the road-side edge of the north platform. At first glance, they appear to be art.  We certainly designed them to be attractive in their own right, although they are also capable of mounting outdoor art displays.  Curved like the sails on a boat, they’re framed in glass, with posts made of aluminum.

a peaceful wait

Although they look so decorative, they’re actually designed to be functional, and to make waiting on the outside platform a more peaceful experience.

So when you get a chance to visit the north YRT/Viva platform at the VMC, go stand near the windscreens, and see for yourself how we’ve been able to make standing outside a nicer experience, even in a breezy place like the middle of Highway 7.

 

safety in waiting

Monday, November 20th, 2017

Bus rapid transit (BRT) systems like viva use a variety of design features to make travel faster, but the primary feature is dedicated transit lanes that allow buses to bypass regular traffic. BRT systems around the world take different approaches as to where those lanes go. Some use separate lanes beside the roadway. Here in York Region, the vivaNext system uses median rapidways that run down the centre of the road.

median benefits

A major benefit of median rapidways is how they minimize conflicts with driveways and business access. However, this design requires passengers to wait for their buses in the middle of high-volume thoroughfares – such as Highway 7 West at the new Vaughan Metropolitan Centre rapidway station. Utmost consideration was given to design strategies that ensure the safety of passengers while they wait for their buses.

crash-load strength

The VMC Station’s most crucial safety protection are the white concrete barrier walls which run the length of the station on both sides, separating the waiting area from traffic lanes. With the wall’s white architectural concrete finish, curves that echo those on the station roof and tapering design that flows into the planters and ramps near the crosswalk, this wall is a key aesthetic feature of the new station. But don’t be fooled by its good looks: this wall is a brute.

It’s designed to withstand crash loads, the potential forces involved in a traffic collision. Crash-proof walls have to meet strict criteria on factors such as design, materials and construction. These specifications are set by Ontario Provincial Standards, and before we received approval to begin construction, every element of the design was scrutinized to ensure it met or exceeded those requirements.

standard scrutiny

Design standards dictate things like the height and thickness of the wall, how much rebar – steel reinforcements – is incorporated, how much it will weigh, and how the wall will be fixed to the base. Standards apply to the type of materials used for the concrete wall, the aggregate used to mix the concrete, the steel used in the rebar, even the coatings on the steel. Likewise, standards dictate the construction itself, ranging from how the concrete is cured to how edges are finished.

Although safety comes first, we made sure it looks good, too.

So now you know all the thought that went into protecting you while you wait for your YRT/Viva bus, we hope you admire the design of the station, relax, and enjoy this impressive new addition to the Vaughan Metropolitan Centre.

a modern take on the ancient dome

Wednesday, November 15th, 2017

Here’s a question: what do some of the most impressive structures in the world, including many of the great cathedrals of Europe and the Pantheon in Rome, have in common with our new bus rapid transit station at the Vaughan Metropolitan Centre?

The answer: they’ve all followed the same basic construction technique for building a dome, which has been around for at least 2,000 years.

Domes have traditionally been reserved for a select number of important buildings which need to be impressively open and dramatic. Another reason there aren’t a lot of domes is because they’re more difficult to build compared to standard rectangular buildings. We loved the idea of creating an open and airy space for the Vaughan Metropolitan Centre rapidway station, making it big enough for viva buses to drive right through. We also wanted it to be special, and symbolic of Vaughan’s new downtown.

Although building materials may have evolved over the past 2,000 years, the general approach for building domes hasn’t really changed. First, strong, deep foundations are constructed to take on the full weight of the dome. Then, a temporary support structure is built. Gradually the permanent exterior shape is created up around the support structure until the dome is closed at the top. Once the dome is complete and able to support itself, the temporary support structure is removed, piece by piece.

Ancient domes would have had wooden temporary support structures, with the outer dome made of stones added one at a time. Although the materials we used are modern, we followed the same classical construction technique. First we built a steel temporary structure. Over that we installed the station’s outer dome, a steel frame welded together one segment at a time.

With the outer steel structure fully installed and all the structural welding complete, we carefully removed the temporary support structure one piece at a time, which took a couple of weeks. After this process was complete, construction inside the station began.

All the weight of the station is supported by the subway structure underneath the station, and 25 metre-deep piles or caissons which extend underground to the same level as the subway.

With its glass and steel shell exterior and high-tech comfort and amenities inside, we know you’re going to love using our new station for its modern look and functionality. But you can be proud of the fact that, from an architectural standpoint, it’s joining a pretty special group of buildings that have been built to stand the test of time.

rain, rain, go away

Monday, November 13th, 2017

Our new rapidway station at Vaughan Metropolitan Centre is ready for the rain, innately designed to handle a downpour and keep those pesky puddles off the road.

Large structures like the new bus rapid transit station shed a lot of rain during storms. With the size of the station’s roof, the volume of water collecting from even light rain storms would be enough to create some pretty major puddles.

Water management has been a key design consideration for the station since day 1. Letting runoff drain freely onto the roads isn’t an option since the station is right in the middle of Highway 7. Here’s the rundown on how we’re managing runoff.

Water management strategy includes features built into the station’s design, and the design of the road and storm water management systems around the station.

Gutters run along the curved station roof between the skylight and the roof panels, designed to collect and funnel water to the ends of the station. At that point, brow gutters – shaped like eye-brows – will drain the water into downspouts on the sides of the station, which then drain safely into underground catchbasins connected to the storm water management system.

But that’s not all! Water from the middle portion of the roof, below the roof gutters, will drain off the roof onto the road. Generally at our vivastations, the road design ensures water doesn’t become puddles.  A very gradual slope away from the station to the curb lane directs the water into a series of curbside storm sewers and catch basins.

However, the VMC station is so much larger than the other stations, there’s simply too much water to direct across the road. Instead, we drain the water closer to the station.

We’ve built up the road surface so that its highest point is 1.2 metres away from the station.  Water draining off the station will be naturally directed back towards the station, running along the curb into a series of catchbasins and into the storm sewers.

We know that rain gutters and catchbasins aren’t the most glamourous features of the new station, but on a rainy day, we’ll all be glad they’re there.