- Material
- Concrete
- Typical application
- Gravity drainage and sewer infrastructure
- Important distinctions
- Pipe surface, cracks, joints and movement
- Repair evidence
- Survey, dimensions and service conditions
Concrete drainage systems
A concrete drain includes the pipe barrel, joints and its connections to chambers or other pipe materials. The failed part matters: a crack in one length is not the same fault as an offset joint or continuing movement.
On commercial and industrial systems, the discharge matters as well. Any repair material has to suit the actual effluent and operating conditions; the description “concrete drain” is not enough to establish compatibility.
Survey quality and visible defects
Deposits, standing water and restricted access can hide defects. The survey should separate what was visible from sections that could not be assessed. If cleaning is needed, the method has to suit the pipe condition and the material being removed.
Pipe dimensions, the length of the affected section, branch positions and the route through chambers help determine whether the defect is local or needs a different repair or access arrangement.
Lining limits and hydraulic considerations
Internal lining should only be selected after the host-pipe condition and the installation requirements of the chosen system have been assessed. Collapse, major displacement or ongoing external movement can make straightforward lining unsuitable.
A liner also takes up part of the existing bore. Where capacity matters, the hydraulic assessment should use the finished geometry and condition of the route rather than assume that a smoother internal surface proves adequate capacity.
Repair scope and completion evidence
The repair specification should identify the defects being treated, how connections will be dealt with and the checks made on completion. The original assessment should remain with the completion evidence, especially where excavation or further design work is still required elsewhere on the system.