Rehabilitation of large profiles lacking long-term stability

Many large interceptor sewers, predominantly installed under public roads, have been in use for over 100 years. They are made of brickwork or compressed concrete and often show serious damage, so that it would seem that long-term stability can no longer be guaranteed. As an alternative to replacing large profiles, various renovation procedures offer significant advantages with respect to investment costs, environmental protection and urban pollution. Depending on the procedure, it may well be possible to extend the service life, in order to match that of a replacement. However, beforehand, an in-depth study of the current stability and residual load capacity of the existing sewer is required, along with needs-based selection and dimensioning of the rehabilitation procedure. The new standard DWA-A 143-2 serves as a good basis for the necessary static calculations.