A new testing technique named advanced expansion due to compression (A-EDC) has been developed with an attempt to study the hoop
mechanical behavior of Zircaloy-4 cladding under the pellet-cladding mechanical interaction (PCMI) and the presumed reactivity-initiated accident
(RIA). The Zircaloy-4 used in this work showed elongated grains in the tube longitudinal direction, large amounts of residual strain, and
crystallographic texture. The nite element method (FEM) analysis illustrates that the A-EDC test shows a uniaxial tension in the hoop direction,
which has also been conrmed by experiments. In addition, the hoop stress-strain curve has been derived at room temperature by the A-EDC
tests. Moreover, the fractured surface has been observed in this research.