Selection of the appropriate class of liners in trenchless renewal of concrete sewers

Abstract

In the case of long-used sewers requiring trenchless renewal, it is important to select the appropriate class of renewal liners, i.e. determine whether they should be structural, partially structural or non-structural. The most frequently used methods in Poland for calculating the loads from the weight of the soil acting on sewers with a rigid structure were presented. A 5-step procedure was proposed to select the appropriate class of renewal liners. A specific calculation example regarding corroded concrete sewers is also included, showing how important it is to select the appropriate method of combining the loads acting on the pipes and, therefore, indicating its significance on the influence of the pipes’ ground surroundings on the amount of stresses occurring in them. The discussion of the results made it possible to formulate recommendations regarding the selection of an appropriate group of renewal liners for sewers requiring trenchless renowal.