Limit analysis on aging penstocks based on linear programming

Abstract For the limit analysis of aging penstocks used in hydraulic power facilities, it would be difficult to apply analytical methods and finite element approaches because of the large size and complex failure mode of the structure, and also due to the cost. The present paper shows that linear programming (LP) could effectively solve these problems, as the limit analysis of an aging penstock is carried out using a combined approach of LP and an analytical solution for the plastic deformation at the limit state. Based on the numerical results, such factors influencing the limit load are discussed as the wall thickness and the span length between anchor blocks. Then, a quantitative evaluation method based on the limit load is proposed for assessing the structural stability of an aging penstock.