Theoretical and numerical analyses of hydrostatic buckling of a noncircular composite liner with arched invert

• Buckling failure of a noncircular liner was studied theoretical and numerically.
• Theoretical solution to the buckling of invert composite liner was presented.
• FE method was successfully employed for nonlinear and contact analyses.
• The two solutions were verified by the good agreement of their results.

This study considered the hydrostatic buckling failure of a noncircular composite liner with an arched invert installed in the sewer pipe. An equation was derived for the buckling of the invert liner, and its application procedure was proposed. A finite-element method was successfully employed for nonlinear and contact analyses of the buckling behaviour and the physical contact phenomena of different sewer culverts. Generally, the composite liner fails in a single-lobe buckling at the invert with the deflection similar to that observed onsite. The proposed theoretical solution was verified through numerical analysis; the critical pressure and buckling mode results showed good agreement.