岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2014年
3期
493-499
,共7页
吴创周%石振明%付昱凯%杨林德%李秋实
吳創週%石振明%付昱凱%楊林德%李鞦實
오창주%석진명%부욱개%양림덕%리추실
岩石力学%蠕变试验%蠕变变形%层理各向异性特性
巖石力學%蠕變試驗%蠕變變形%層理各嚮異性特性
암석역학%연변시험%연변변형%층리각향이성특성
rock mechanics%creep test%creep deformation%bedding anisotropy characteristic
为了解锦屏二级水电站引水隧洞绿片岩的各向异性流变力学特性,通过对层状脆性绿片岩试件进行单轴压缩蠕变试验,研究脆性层状岩石材料的各向异性蠕变规律。按层理面倾角大小共加工6个试件,分级加载均为4个应力水平,最大值与初始地应力接近。试验结果表明,绿片岩试件蠕变曲线存在瞬时应变、衰减蠕变和稳定蠕变,未出现加速蠕变阶段。根据试验结果得到瞬时弹性模量和稳定蠕变阶段的蠕变速率。分析表明,绿片岩试件的瞬时弹性模量随着应力水平的提高而提高,并趋于稳定,其中层理倾斜的试件瞬时弹性模量更高;蠕变速率随着应力水平的提高而提高,并随着层理面倾角的增大而增大,层理面倾角接近材料的破裂角时,试件的轴向蠕变速率最大。
為瞭解錦屏二級水電站引水隧洞綠片巖的各嚮異性流變力學特性,通過對層狀脆性綠片巖試件進行單軸壓縮蠕變試驗,研究脆性層狀巖石材料的各嚮異性蠕變規律。按層理麵傾角大小共加工6箇試件,分級加載均為4箇應力水平,最大值與初始地應力接近。試驗結果錶明,綠片巖試件蠕變麯線存在瞬時應變、衰減蠕變和穩定蠕變,未齣現加速蠕變階段。根據試驗結果得到瞬時彈性模量和穩定蠕變階段的蠕變速率。分析錶明,綠片巖試件的瞬時彈性模量隨著應力水平的提高而提高,併趨于穩定,其中層理傾斜的試件瞬時彈性模量更高;蠕變速率隨著應力水平的提高而提高,併隨著層理麵傾角的增大而增大,層理麵傾角接近材料的破裂角時,試件的軸嚮蠕變速率最大。
위료해금병이급수전참인수수동록편암적각향이성류변역학특성,통과대층상취성록편암시건진행단축압축연변시험,연구취성층상암석재료적각향이성연변규률。안층리면경각대소공가공6개시건,분급가재균위4개응력수평,최대치여초시지응력접근。시험결과표명,록편암시건연변곡선존재순시응변、쇠감연변화은정연변,미출현가속연변계단。근거시험결과득도순시탄성모량화은정연변계단적연변속솔。분석표명,록편암시건적순시탄성모량수착응력수평적제고이제고,병추우은정,기중층리경사적시건순시탄성모량경고;연변속솔수착응력수평적제고이제고,병수착층리면경각적증대이증대,층리면경각접근재료적파렬각시,시건적축향연변속솔최대。
In order to study the time-dependent deformation behavior of bedding anisotropy green schist of Jinping II hydropower station,this paper investigates the creep behavior of brittle bedding anisotropy rock by uniaxial compression creep experiments in laboratory. Six specimens were prepared with different inclination angles of bedding planes. Loading stress levels were graded 4 classes,and the maximum value of them were all approximately equal to the existing maximum initial geostress. All the strain-time curves of specimens did not exhibit the accelerated creep stage. The instantaneous elastic modulus and steady-state creep rate of specimens were obtained and analyzed based on the experiments data. The results show that the instantaneous elastic modulus of the specimens increases with the increment of stress level;and they were higher when the bedding planes are oblique to the compression direction;and the steady-state creep rate of the specimens increase with the increment of both stress level and the inclination angle of bedding planes;it reaches the maximum value with the inclination angle of the specimen close to the failure angle of rock.