Surveyor

Surveyor

LNT/S/1248620

Heavy Civil InfrastructureKolkata
- Posted On
- 28 Jan 2025
- End Date
- 27 Jul 2025
- Required Experience
- 3 - 8 Years

**Skills**:
Knowledge & Posting Location

SURVEYING

Minimum Qualification

ITI SURVEYOR

**Job Description**:
**1. Pre-Construction Surveying and Planning**:

- ** Site Analysis and Boundary Identification**: Before construction begins, surveyors conduct initial site surveys to establish project boundaries, rights-of-way, and other critical reference points. This is necessary to ensure that the tunnel and station locations are legally defined and aligned with urban planning regulations.
- ** Topographical Surveys**: The surveyor conducts topographical surveys to map the existing surface conditions, including roads, buildings, utilities, and other structures. This is crucial for planning how the tunnel will intersect with surface infrastructure and identifying potential obstacles or challenges.
- ** Geodetic Control Setup**: They establish geodetic control points, which serve as the reference framework for all construction activities, ensuring that the tunnel, stations, and other elements are accurately positioned in relation to one another and the project site.

**2. Tunnel Alignment and Positioning**:

- ** Tunnel Design Alignment**: Surveyors are involved in verifying and marking the proposed alignment of the tunnel, ensuring that the design aligns with the planned trajectory. This requires careful calculations to account for elevation, horizontal alignment, and curvature based on the engineering design.
- ** Monitoring Tunnel Progress**: Throughout the construction phase, surveyors monitor the position of the tunnel boring machine (TBM) or other excavation methods, ensuring that the tunnel remains on the correct alignment. They use advanced equipment, such as laser scanning, total stations, and GPS, to track the TBM's progress and verify that the excavation matches the design specifications.
- ** Cross-Section Measurements**: Regular cross-sectional surveys are conducted to monitor the shape and size of the tunnel as it is being excavated. This helps ensure that the tunnel profile meets the design specifications, particularly in complex geological conditions.

**3. Subsurface Utility and Obstruction Mapping**:

- ** Locating Existing Utilities**: The surveyor is responsible for identifying and mapping existing underground utilities (e.g., water pipes, gas lines, electricity cables) that could pose challenges during tunneling or excavation. They use ground-penetrating radar (GPR) and other methods to detect and record the location of utilities.
- ** Collision Avoidance**: The surveyor’s role is critical in avoiding clashes between the proposed tunnel and existing infrastructure. By accurately mapping utilities and other subsurface obstacles, they help ensure that the construction process avoids costly and dangerous encounters with these elements.

**4. Monitoring and Quality Control During Construction**:

- ** Monitoring Tunnel Stability**: Surveyors use precision tools to monitor tunnel movements and settlements during construction, ensuring that ground movements and subsidence are within acceptable limits. This is particularly important in urban areas, where tunnel excavation could affect nearby buildings, roads, and other structures.
- ** Surface and Underground Settlements**: They conduct surveys to measure surface movements and settlements resulting from tunneling activities. If any unexpected shifts or subsidence are detected, surveyors can help engineers adjust construction techniques to mitigate damage.
- ** Alignment and Elevation Control**: Throughout the tunneling process, the surveyor ensures the tunnel’s vertical and horizontal alignment is maintained. They regularly check the depth of excavation and the alignment of the tunnel, making corrections where necessary to maintain the correct path.

**5. Setting Out and Marking for Construction**:

- ** Station and Tunnel Lining Marking**: The surveyor is responsible for marking out the exact locations for tunnel linings, underground station structures, shafts, and other critical components of the metro system. This ensures that the construction team builds structures in the correct locations and according to the design.
- ** Reference Points for Structural Work**: They provide reference points for the construction of tunnel linings, station foundations, and other key structures. These points are essential for accurately positioning rebar, foundations, and other construction materials.

**6. Post-Construction Surveying**:

- ** Final As-Built Surveys**: After construction, surveyors conduct an as-built survey to document the final location, alignment, and elevation of the tunnel and stations. This serves as a record for the completed project and is essential for future maintenance or upgrades.
- ** Verification of Construction**: The as-built survey helps verify that the project was constructed accordi