STM - Jean-Talon Metro Station
Client / Collaborator
Société de transport de Montréal [STM]
Sector
Architecture, Infrastructure, Transport
Location
Montreal
Services
Relevé LiDAR
Mandate
To support the planning and coordination of future works at Jean-Talon station, DGTL carried out 3D digitization of the station's three tracks, including the orange and blue line interchange. The orange line has a double track, while the blue line has two single tracks. The digitization also had to cover the first 30 meters of tunnel on each side for each track.
Avec un objectif clair et exigeant : obtenir une représentation complète, mesurable et exploitable de l’infrastructure, avec une précision de quelques millimètres. Au-delà de la capture, la qualité devait être démontrée, avec des statistiques de contrôle et des rapports de qualité permettant de valider la fiabilité des données pour le dessin, l’analyse et la prise de décision.
Mandate
To support the planning and coordination of future works at Jean-Talon station, DGTL carried out 3D digitization of the station's three tracks, including the orange and blue line interchange. The orange line has a double track, while the blue line has two single tracks. The digitization also had to cover the first 30 meters of tunnel on each side for each track.
Avec un objectif clair et exigeant : obtenir une représentation complète, mesurable et exploitable de l’infrastructure, avec une précision de quelques millimètres. Au-delà de la capture, la qualité devait être démontrée, avec des statistiques de contrôle et des rapports de qualité permettant de valider la fiabilité des données pour le dessin, l’analyse et la prise de décision.
Proposition
In order to obtain a defensible geometric basis and complete documentation of the metro station station, we propose a methodology structured around a control network, followed by two parallel LiDAR acquisitions, both linked to the same reference frame.
Primary control network
We propose the implementation of a high-precision control network, established by a series of resections and validated by numerous control points (checkshots). Each resection is performed with millimeter precision, and the network's residuals remain well below the 5 mm threshold required by the STM.
LiDAR scanning, two complementary approaches
To document the site accurately and compare technologies, we propose two parallel LiDAR surveys: a SLAM survey and a terrestrial LiDAR survey. This approach allows us to measure differences in accuracy, precision, and completeness, while ensuring consistent linkage to the main control network.
X-ray elevations to speed up drawing
To reduce drawing time and facilitate equipment identification, we offer orthogonal X-ray-type views in black and white, to scale. These elevations serve as a direct basis for tracing, coordination, and plan validation.
Deliverables
Control network and quality report
From the main control network, we deliver the position of each control point, accompanied by a detailed quality report. This report presents the network statistics and residuals, the quality of the observations, the adjustments made, the number of data sets, and the instruments used. This step is crucial as it ensures that the geometric relationship between the three tunnels is accurate, especially considering that the scanned length per tunnel exceeds 210 m.
High-precision color point clouds
We deliver two sets of color point clouds: one from SLAM LiDAR and one from Terrestrial LiDAR. Both datasets are linked to the main control network to ensure stable, measurable, and verifiable geometry.
Scaled orthogonal "X-Ray" views
We deliver a series of scaled orthogonal views (elevations and sections) X-Ray style images, facilitating the identification of electrical equipment and conduits, as well as the interpretation of spatial relationships between different platforms and tracks.
