Telecom Surveying
Tower sites and fiber routes. El-Eman Office provides telecom network surveying.
Selecting tower sites and analysing line of sight
In telecom network surveying, a tower site study starts from the topographic map and an elevation model, used to analyse the line of sight between sites and identify obstructions such as hills and tall buildings. The proposed site is then taken to the ground and checked for suitability.
- Confirm ownership or right of use of the site and its exact boundaries.
- Observe the distances from roads, buildings and facilities as required by the applicable regulations.
- Study access for moving equipment and for bringing in power and fibre.
- Set out the tower centre, foundation positions and guy anchors with precise coordinates.
Vertical alignment and setting out foundations
Lattice and monopole towers are sensitive to tilt, so their verticality is monitored during and after erection with survey instruments. Guy anchors for guyed towers are set out at symmetrical angles and distances around the base, and the foundation levels at each point are checked so differences do not cause uneven load distribution. Anchor bolts are set before the pour, because an error in them is hard to fix once the concrete has hardened.
Cable routes and documentation
Laying optical fibre needs a route that avoids obstacles and respects road reserves and existing utilities. The work goes through stages:
- Study the route on maps and identify utilities it may cross.
- Locate existing utilities by ground-penetrating radar or trial pits where necessary before digging.
- Set out the route, chambers and manholes on the ground with defined coordinates and depths.
- Follow the execution and check depths and gradients.
- Prepare as-built drawings recording the true positions of the cables and chambers.
As-built drawings matter a great deal for maintenance and fault repair, or when other projects are carried out in the area, because they prevent cables being cut by mistake and shorten the time needed to locate a fault. It is best to link them to a GIS database that allows searching and updating.
Frequently asked questions
Why do we need as-built drawings for fibre networks?
Because the route as built may differ from the design due to obstacles in the field, and the actual drawing is the reference for maintenance, locating faults and avoiding conflicts with later works.
How is a buried cable detected before digging?
Ground-penetrating radar or a cable locator is used depending on the type of utility, together with old drawings. Trial pits may be needed at critical points because instruments may not detect everything.
What setting-out accuracy do tower foundations need?
It is set by the project's technical specifications, but the most important thing is the relative accuracy of the axes between foundations and their level, since this governs fitting the tower structure without extra stress.
