Method in which access is gained by excavation from ground level to the required level underground for the installation, maintenance or inspection of a pipe, conduit or cable. The excavation is then backfilled and the surface reinstated.
Methods of tunnel construction ranging from manual excavation to the use of self propelled tunnel boring machines. Where a lining is required bolted segmental rings are frequently used.
For brick manholes this term is sometimes used in place of cone, and indicates the gradual reduction in diameter by indenting brick.
That part of a sewer network containing the critical sewers, and other sewers where hydraulic problems are severe and merit detailed investigation.
The destruction of a material or its properties because of a reaction with its (environment) surroundings.