ABSTRACT
Economical design of a fibre reinforced segmental lining relies on being able to resist the concentrated axial forces at the joint. It has long been known that eccentricities resulting from rotations of the joint due to build inaccuracies can significantly reduce joint capacity. However, most design methods used today rely on analysis that assume that the ring is built perfectly, leaving the designer with the difficult task of assessing how much additional eccentricity should be applied to account for build tolerances. Methods that exist to account for this rotation are often conservative, leading to higher concrete strengths or even thicknesses being specified.
A new technique for incorporating this tolerance into a ring design has been proposed by Rauch et al. (2024), who evaluated the method for establishing maximum bending moment using a simple bedded beam model. This paper extends the application of the method by using it to establishing the joint eccentricities, and then translating them into joint capacities for a fibre reinforced ring, resulting in a less conservative method of accounting for joint tolerance on joint strength.
Having described the theory, the paper demonstrates its application through a real project example, and shows how the build tolerance can have a material impact on the strength of the joint.
