分级加载浸水泥质粉砂岩声发射分形特征试验研究  

Experimental study on acoustic emission fractal characteristics of soaked argillaceous siltstone under uniaxial leveling loading

作　　者：宋浩然 许家臣 张庆文 郭永发[2] 许国权 李涛 SONG Haoran;XU Jiachen;ZHANG Qingwen;GUO Yongfa;XU Guoquan;LI Tao(College of Civil Engineering,Southwest Forestry University,Kunming 650224,China;Kunming Survey,Design and Research Institute Co.,Ltd.,CREEC,Kunming 650200,China;The 5th Engineering Co.,Ltd.,China Railway 1 Bureau Group Corporation,Baoji 721006,China)

机构地区：[1]西南林业大学土木工程学院,云南昆明650224 [2]中铁二院昆明勘察设计研究院有限责任公司,云南昆明650200 [3]中铁一局集团第五工程有限公司,陕西宝鸡721006

出　　处：《人民长江》2023年第1期151-157,共7页Yangtze River

基　　金：国家自然科学基金项目(51768065);云南省科技厅重点研发计划(社会发展)(2018BC008);滇中引水Ⅱ标科研项目(XLKK-333-2021-024);中国中铁科技研究开发计划课题(2020-重大专项-04)。

摘　　要：为探究不同浸水时间对泥质粉砂岩加载破坏过程的影响,以天然状态、浸水1,3,7 d状态下滇中引水工程大理Ⅱ标段板凳山隧洞的泥质粉砂岩为样品,进行单轴分级加载试验,监测岩样从加载至破坏的全过程声发射(AE)活动。试验表明:(1)随着浸泡天数的增加,AE累计振铃计数逐渐衰减,在分级加载时,天然岩样的累计振铃计数曲线有明显上升台阶,浸水岩样的累计振铃计数曲线的跃升主要集中在破坏阶段。(2)天然岩样较浸水岩样的脆性更强,破坏时AE活动频度较高,表现为AE定位点在主破裂面附近泵集,破坏面附近定位点的能级较浸水岩样高1~2个能级。(3)随着加载应力增加,浸水岩样的含水率越高,岩样的破裂损伤阶段较天然岩样有所提前,AE定位点主要集中在破坏阶段,定位点数量的激增更加明显,这与振铃计数的变化规律相吻合。(4)不同含水率岩样在相对破坏应力80%之前,关联维数均呈现上升的趋势,在相对应力的80%附近关联维数上升至最大值,应力继续增大,岩样破坏,关联维数跌落至最小值,不同含水率岩样的关联维数最小值均介于0.020~0.035之间。以上岩样的破坏特点可为隧洞涌水情况下岩体稳定性监测提供参考依据。In order to understand the loading failure process of argillaceous siltstones under different days of soaking.A uniaxial loading test was carried out on the argillaceous siltstones of the tunnel in Dali Ⅱ section of the Central Yunnan Water Diversion Project under natural state, soaking for 1 day, 3 days and 7 days respectively, and we monitored the acoustic emission activity in the whole process of rock′s loading to failure.The results showed that:(1) AE cumulative ringing count decreased with the increase of soaking days.The cumulative ringing count curve of natural rock specimens had an obvious upward step compared with that of soaked rock specimens during the graded loading, while the increase of cumulative ringing count curve of soaked rock specimens mainly occurred in the failure stage.(2) The brittleness of natural rock specimens was stronger, and the AE activity frequency was higher during failure stage, which was mainly manifested as the cluster of AE location sites neared the main failure surface, and the energy level of AE location sites near the failure surface was higher than that of the soaked rock specimens by 1~2 energy levels.(3) With the increase of loading stress, the higher the moisture contents of the soaked rock specimens were, the fracture damage stages of the soaked rock specimens came earlier than that of the natural rock specimens, and the AE location sites were mainly concentrated in the failure stage.The surge of the number of AE location sites was more obvious, which was consistent with the change law of AE ringing count.(4) Before 80% of failure stress of rock specimens, the correlation dimension showed an increasing trend, and it reached the maximum value around 80% of failure stress.As the stress continued to increase, rock specimens were damaged with correlation dimension dropping to the minimum level, and the minimum values of correlation dimension of rock specimens with different moisture content were between 0.020 and 0.035.The failure characteristics of the rock specimens

关 键 词：泥质粉砂岩 含水率 声发射振铃计数 分形特征 时空演化 

分 类 号：D346.5[政治法律—政治学]