Experimental investigation of creep failure behavior of sandstone with combined pore–fissure defects
- 1Department of Mechanics and Engineering, Liaoning Technical University, Fuxin, Liaoning 123000, China
Abstract
Internal defects is a primary intrinsic factor governing the deformation and failure of rocks under load. To elucidate the effects of pore–fissure combined defects on the creep behavior of rocks, a series of step-loading creep tests were conducted, with particular emphasis on the effects of pore location and diameter on creep evolution. The fracture process was monitored using acoustic emission (AE) and digital image correlation (DIC) techniques. The results show that: (1) pore position significantly affects creep duration, which is shortest when the pore is located at z position; creep duration varies in a “V-shaped” trend with increasing pore diameter. (2) the long-term strength generally decreases with larger pore diameters, reaching its minimum at the z position with a 3 mm diameter pore. During creep, the cumulative AE ringing exhibits a stepwise increase and undergoes an abrupt surge immediately before failure. (3) in the failure stage, the AE b-value transitions from fluctuating to a sustained decline, serving as a clear precursor to instability. (4) Pore spatial position exerts a dominant control over the macroscopic fracture pattern, whereas pore size primarily induces local variations. However, when the pore diameter reaches 4 mm, semi-enveloping crack propagation around the pore is observed. These findings demonstrate that pore position and size jointly control the temporal evolution of creep failure, long-term strength degradation, and crack propagation patterns. The results provide important experimental evidence for long-term strength prediction, failure mode analysis, and instability precursor identification in defect-containing rock masses.
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BibTeX
@article{zhao2026experimental,
title = {{Experimental investigation of creep failure behavior of sandstone with combined pore–fissure defects}},
author = {Na ZHAO and Yu WEN and Laigui WANG},
journal = {Zhongguo dizhi zaihai yu fangzhi xuebao},
year = {2026},
month = aug,
doi = {10.16031/j.cghc.202510003},
url = {https://doi.org/10.16031/j.cghc.202510003},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Experimental investigation of creep failure behavior of sandstone with combined pore–fissure defects
AU - Na ZHAO
AU - Yu WEN
AU - Laigui WANG
PY - 2026
DA - 2026/08/01
JO - Zhongguo dizhi zaihai yu fangzhi xuebao
DO - 10.16031/j.cghc.202510003
UR - https://doi.org/10.16031/j.cghc.202510003
AB - Internal defects is a primary intrinsic factor governing the deformation and failure of rocks under load. To elucidate the effects of pore–fissure combined defects on the creep behavior of rocks, a series of step-loading creep tests were conducted, with particular emphasis on the effects of pore location and diameter on creep evolution. The fracture process was monitored using acoustic emission (AE) and digital image correlation (DIC) techniques. The results show that: (1) pore position significantly affects creep duration, which is shortest when the pore is located at z position; creep duration varies in a “V-shaped” trend with increasing pore diameter. (2) the long-term strength generally decreases with larger pore diameters, reaching its minimum at the z position with a 3 mm diameter pore. During creep, the cumulative AE ringing exhibits a stepwise increase and undergoes an abrupt surge immediately before failure. (3) in the failure stage, the AE b-value transitions from fluctuating to a sustained decline, serving as a clear precursor to instability. (4) Pore spatial position exerts a dominant control over the macroscopic fracture pattern, whereas pore size primarily induces local variations. However, when the pore diameter reaches 4 mm, semi-enveloping crack propagation around the pore is observed. These findings demonstrate that pore position and size jointly control the temporal evolution of creep failure, long-term strength degradation, and crack propagation patterns. The results provide important experimental evidence for long-term strength prediction, failure mode analysis, and instability precursor identification in defect-containing rock masses.
SN - 1003-8035
ER -