长江科学院院报2024，Vol.41Issue(11)：163-171,9.DOI:10.11988/ckyyb.20231215
饱水作用对白砂岩损伤破裂及声发射特性的影响
Effect of Water Saturation on the Damage Failure and Acoustic Emission Characteristics of White Sandstone
摘要
Abstract
The instability and failure of surrounding rock in water-bearing weak strata are often closely related to the effects of water.To deeply reveal the influence and mechanical mechanism of water saturation on rock damage and failure,uniaxial compression tests on white sandstone under dry and water-saturated conditions were carried out.Through comparative analysis,the effects and mechanisms of water saturation on strength,deformation,stress thresholds,strain energy,and acoustic emission characteristics were studied.The results showed the following when the white sandstone was water-saturated:(1)Uniaxial compressive strength and elastic modulus decrease,while Poisson's ratio increases.(2)The normalized crack initiation stress(σci/σf)decreases.The analysis shows that the softening effect of water weakens the bonding between mineral particles,making new cracks easier to initiate,thus leading to a decrease in σci/uf.(3)The normalized crack damage stress(σcd/σf)decreases.Based on the a-nalysis of the AE b-value,the proportion of small-scale ruptures increases.The increase in the proportion of small-scale fractures makes it easier for microcracks to coalesce into macrofractures,leading to a decrease in σcd/σf.(4)The total energy(U),elastic energy(Ue),and dissipated energy(Ud)at peak strength decrease,and the ratio of elastic energy to total energy(Ue/U)also decreases.(5)The analysis based on AE RA value(ratio of rise time to amplitude)and AF value(average frequency)shows that the proportion of shear fractures increases after water sat-uration,making it easier to produce intragranular fractures.The research results provide important insights into the failure mechanisms of water-saturated rocks.关键词
白砂岩/饱水/应力门槛值/能量演化/损伤破裂/声发射Key words
white sandstone/water saturation/stress thresholds/energy evolution/damage failure/acoustic emis-sion分类
天文与地球科学引用本文复制引用
胡玉波,房敬年,徐荣超,郝小红,阎震,周文朋,李震..饱水作用对白砂岩损伤破裂及声发射特性的影响[J].长江科学院院报,2024,41(11):163-171,9.基金项目
国家自然科学基金项目(51709113,51704097) （51709113,51704097）
河南省重点研发专项(241111322900) （241111322900）
河南理工大学自然科学基金项目(J2021-2) （J2021-2）
