摘要
针对四川地区红层软岩吸水膨胀引起的路基上拱、衬砌开裂等问题,以取自四川省某引调水工程的粉砂质泥岩和泥质粉砂岩为对象,通过试验手段研究其膨胀特性。试验结果表明,红层软岩膨胀变形与膨胀力均具有非线性时效演化规律;粉砂质泥岩极限膨胀力在0.20~0.60 MPa,极限膨胀应变1.00%~2.00%,而泥质粉砂岩极限膨胀应力小于0.1 MPa,极限膨胀应变小于0.10%。岩石极限膨胀应力/应变均与膨胀持续时间呈正相关关系,且黏土矿物含量越高,岩石膨胀性越强。结果证明三组典型粉砂质泥岩为弱膨胀性岩石,而泥质粉砂岩为微膨胀性岩石,并针对不同膨胀性围岩的隧洞设计施工提出了建议措施。
To address engineering issues such as roadbed uplift and lining cracks caused by water-absorbing swelling of red-bed soft rocks in Sichuan,this study experimentally investigated the swelling characteristics of silty mudstone and argillaceous siltstone collected from a water diversion project.The results demonstrate that both swelling deformation and pressure of these rocks follow nonlinear time-dependent evolution patterns.The silty mudstone exhibited ultimate swelling pressures of 0.20~0.60 MPa with 1.00%~2.00%ultimate swelling strain,while the argillaceous siltstone showed significantly lower values(<0.1 MPa swelling stress and<0.10%strain).Both ultimate swelling stress and strain displayed positive correlations with swelling duration,and higher clay mineral content resulted in stronger swelling potential.The findings classify the three typical silty mudstone samples as weakly expansive rocks and the argillaceous siltstone as minimally expansive,and suggestion on engineering design and construction were proposed in terms of tunnel surrounding rock with different expansibility.
作者
宋伟伟
李杰
肖明砾
郑兆强
SONG Weiwei;LI Jie;XIAO Mingli;ZHENG Zhaoqiang(Sichuan Daqiao Hydropower Consulting and Supervision Co.,Ltd.,Chengdu 610072,China;College of Water Resources and Hydropower,Sichuan University,Chengdu 610065,China)
出处
《四川建材》
2025年第8期102-104,127,共4页
Sichuan Building Materials
基金
国家自然科学基金面上项目(52479106)。
关键词
红层软岩
膨胀性
极限膨胀力
黏土矿物
光学显微
red-bed rock
expansibility
ultimate expansive force
argillaceous mineral
optical microscope
