Eastern REM: 500 m underground is viable

Yes, today it is possible. Today we came up with a solution to have some part in the tunnel, CPDQ Infra Chairman and CEO, Jean-Marc Arbad, was identified on Thursday at ICD RDI. He returned to company words last winter, accordingly The aerial project is only possible.

And according to Mr. Arbad, this connection between aerial and underground has many advantages.

This allows you to have a direct connection to the entire underground network in Montreal. What is in the air is more complicated. It also allows a back-station, i.e. a turning zone for trains, which increases the future theoretical frequency of the project., He revealed in an interview with Shoki Live with Patrice Roy.

According to the 33-page document, the CPDQ Infra studied 50 scenarios for the Eastern REM route To reach it Solution.

The first study was conducted in the first quarter of 2021 by the Canadian-American engineering firm Aecom-Systra, backed by the French group Sistra. This led to the publication of six underground scenes for the city center, in February.

The second study, presented as a complementary expertise, conducted by the Spanish company Geocontrol SA, which submitted its findings in August.

The Spanish company Geocontrol SA maintained 3D models that integrated the presence of rock and groundwater in the imaginary ways of REM.

Photo: CDPQ Infra

Six other scenarios were studied

In this new compilation, six scenes have been selected for analysis.

The first four scenes are about 4.5 km long tunnels under the Rene-Lowesk boulevard.

The first passes between the yellow and orange lines of the metro with a transition to the wind at the future Cartier station (Jacques-Cartier Bridge). The second also passes between the yellow and orange lines, but with a transition one kilometer east of the Canadian Pacific (CP) tracks.

In the other two illustrations, the tunnel goes deeper than the yellow line. One of them transitions to the wind west of the railroad and the other to the east.

The tunnel under Rs. Saint-Antoine was also studied by geocontrol, but was rejected due to sewage built on this route in 1877.

The sixth and final scene, the New option proposed, A tunnel about 600 meters to the west end of the route, which brings out light rail trains before crossing metro lines.

This optimization is now added to the reference project, Confirmed by Harout Chitilian, Vice President of Corporate Affairs, Development and Strategies at CDPQ Infra.

New option selected: Tunnel less than 600 meters

A new option is the proposed 500-meter tunnel between de Blurie and Robert-Bourassa.

Photo: CDPQ Infra

Geocontrol tried to think outside the box, to find a tunnel solution that would bury the last 600 meters in the route and build the rear station, According to Mr. Chitilian.

This rear station is, from an operational point of view, a major asset.

In particular, as suggested by the CEO of CPDQ, it is possible to increase the frequency of trains and better connect the eastern REM to existing networks. The terminus of the line, Robert-Bourassa station is underground and takes advantage of this route to drop off at Boulevard Rene-Lavesque to switch to the aerial section near the Rue Jean-Mans.

REM de l’Est: Interview with CDPQ Infra President and CEO

The ance image of the route has been questioned

Mark Durand, an engineer in applied geology and geotechnics, considers these to be two very good quality studies. Unfortunately, I found that these two paths were geographically poorly selected. We are targeting complex sectors as there are consolidated deposits. Sherbrook offers the same conditions as any 500 meter tunnel north of the street. They chase problems, but that’s their way, the problem.

When asked about the choice of routes submitted to engineering companies, Harout assured us that Chitilian was there Elbow room. They were asked to study the insertion in the city center, He he said.

Geocontrol wrote in the preface to its report CDPQ was commissioned by Infra to conduct technical and hazard analysis of variants of underground routes in two corridors in downtown Montreal, namely Boulevard Rene-Levesque and Ru Saint-Antoine.

According to Harout Chitilian, All variations on the way out of Rene-Lowesque will significantly penalize the ridership.

He argues that this is not a question of success. These options have cannibalized other networks. Experts looked at scenes that did not work south of Rene-Lavescu.

Accidents of other geological conditions

According to AECOM-Systra, this scenario is not feasible.

Photo: CDPQ Infra

View below Rene-Lavesque between orange and yellow lines, with exit to the east CPCanadian PacificAccording to Aecom-Systra, it is considered impractical.

Failure to respect safety permits for the yellow line, risk of tunnel settling, risk of falling under tracks CPCanadian Pacific There are dangers mentioned.

In total, the average and maximum accidents are 3,590 meters, or 70% of the underground route.

Harrow Chitilian confirms that the part between the lines is very dangerous. This is a probability game where mistakes are very likely to happen. It is also almost certain.

This is not a question of risk taking. Based on what we know, it would be irresponsible to recommend this project in this form.

In the same vein, Geocontrol adds that interruptions to the Metro during construction are inevitable.

Will ridership decrease?

For the idea of ​​going below the yellow line, it initially presents a risk of equipment failure. The Technopark tunnel boring machine has been out of order for nine months, and the ground is similar, Chitilian said. There was a breakage to the head of the equipment. If it happens in the Jacques-Cartier Bridge area, at great depth, it is a very dangerous situation.

The windward transition zone is also Rs. It is impassable at a distance of about 500 meters along the Notre-Dame.

Other risk works: Expected reduction in ridership. CDPQ Infra called on Steer Davis Gleeve to estimate the number of East REM visitors. In this scenario, the label station connected to Berry-Ukam‌ is 40 meters deep, which takes about six minutes extra travel time to access. According to the relevant document from CDPQ Infra, the ridership reduction at this station will be reduced by 56.5%.

Accidents of sagging

Among the effects associated with landscapes, CDPQ Infra lists Instability of large buildings due to soil settlement or subsidy.

However, according to engineer Mark Durand, it is one Misinterpretation of studies. Ekam-Sistra made no mention of the risk of sagging. Geocontrol refers to municipal infrastructure (sewers and aquaculture) and railways CPCanadian Pacific.

They did not mention the buildings, Harout Chitilian said, but said they were inherent hazards of soil change.

M. Durand mentions CDPQ Infra Widely underlines negative aspects. But geocontrol does not imply the impossible. They mentioned the difficulties they needed to find solutions.

According to Mr. Chitilian, In order to maintain adequate adequacy between the project size and the possibility of contracting, selections were made. With the continuous efforts of our architects, it is possible to integrate structures.

This part is in the hands of a committee of 15 multidisciplinary experts, which must submit its report by the end of the fall.