Study on creep characteristics and reduction coefficient of geomembrane under top pressure

Abstract

Abstract A new top-pressure creep test device was developed to simulate the stress conditions of geomembrane in a real working state. CBR puncture and top pressure creep tests under different load levels were conducted using this device to study the creep characteristics of the geomembrane at top pressure. The top pressure creep reduction coefficients under different load levels and design lives were calculated and compared with the regular tensile creep reduction coefficients. Quantitative relationships between the creep-reduction coefficient, design life, and failure strain were established to predict the top-pressure creep-reduction coefficient. The results indicated that the top pressure creep reduction coefficient was greater than that of regular tensile creep. The creep reduction coefficient changed minimally with an increase in the design life. The top pressure creep reduction coefficient remained stable with an increase in the top pressure area strain for different design lives. Based on the results, to improve the safety and durability of engineering structures, the top pressure creep reduction coefficient should be used in the design of geosynthetics affected by the top pressure.