关键词:
Strain rate
摘要:
To investigate the degradation behavior and damage mechanism of sandstone under acid-base erosion and cyclic impact, a series of constant-amplitude impact tests were conducted on acid-base-eroded white sandstone using a split Hopkinson pressure bar test device under four impact pressures, including 0. 12 MPa, 0. 125 MPa, 0. 13 MPa, and 0. 135 MPa. The effects of the impact number, stress-strain response, deformation modulus, and energy evolution were analyzed, and a cumulative damage factor was defined based on the Lemaitre strain equivalence principle. The results indicate that both erosion and impact pressure significantly affect the impact resistance of sandstone. The intact specimens endure up to ten impacts under 0. 12 MPa, whereas eroded specimens fail after fewer than two impacts under 0. 135 MPa. All stress-strain curves exhibit rebound behavior after the peak. With increasing impact cycles, the peak stress and deformation modulus decrease by up to 57. 1% and 86. 1%, while the peak strain, average strain rate, and cumulative specific energy absorption value increase to 0. 136 s, 75. 95 s"1, and 1. 98 J • cm ", respectively. The cumulative damage factor shows a strong negative correlation with the dynamic peak stress (R2 >0. 93), confirming that acid-base erosion and higher impact intensity accelerate crack propagation and exacerbate dynamic failure. © 2026 Chinese Vibration Engineering Society. All rights reserved.