Incremental Failure of an Expansion Joint During Combined Pressure and Expansion Loading

Abstract

Incremental failure was observed when two different loading conditions, pressure and expansion, were applied alternatively to an expansion joint. Neither of the conditions was capable independently of failing the expansion joint. When the conditions occurred together, only a small amount of plasticity was observed. But when the expansion was cycled while holding pressure constant, incremental plastic deformation occurred during each cycle which was cumulative to that of past cycles. The joint was dimensionally unstable over a large number of expansion cycles. Analytical and experimental results are presented in an attempt to explain the observed phenomenon.