岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
4期
951-958
,共8页
巴里坤砂岩%模量%峰值强度%残余强度%三轴试验%饱水度
巴裏坤砂巖%模量%峰值彊度%殘餘彊度%三軸試驗%飽水度
파리곤사암%모량%봉치강도%잔여강도%삼축시험%포수도
Balikun sandstone%modulus%peak strength%residual strength%triaxial tests%saturation
为研究饱水度和围压对砂岩力学特性的影响,在不同围压和饱水度下开展三轴试验,获得了不同饱水度和围压下巴里坤砂岩的模量、峰值强度和残余强度,分析了饱水度和围压对砂岩模量、峰值强度和残余强度的影响规律,结果表明:(1)围压增加,砂岩的模量也增加,围压与模量之间近似为直线关系;饱水度增加,砂岩模量降低,单轴下饱和砂岩的模量降低50.9%;饱水度与砂岩模量之间近似服从直线或负指数函数关系。(2)饱水度增加,峰值强度下降;单轴条件下饱和砂岩的峰值强度下降了44.2%;饱水度与砂岩峰值强度之间近似服从自然对数关系。(3)强度退化指数可以较好地描述围压对残余强度的影响,巴里坤砂岩的强度退化指数与围压之间近似符合负指数关系;随着饱水度增加,砂岩的残余强度降低。(4)随着围压增加,饱水度对砂岩模量、峰值强度和残余强度的影响都减弱。(5)饱水度在60%以下时,饱水度变化对模量和峰值强度的影响显著,当饱水度超过60%后,模量和峰值强度仍随着饱水度增加而降低,但变化速率趋缓;对于残余强度,则饱水度在80%以下时影响显著。
為研究飽水度和圍壓對砂巖力學特性的影響,在不同圍壓和飽水度下開展三軸試驗,穫得瞭不同飽水度和圍壓下巴裏坤砂巖的模量、峰值彊度和殘餘彊度,分析瞭飽水度和圍壓對砂巖模量、峰值彊度和殘餘彊度的影響規律,結果錶明:(1)圍壓增加,砂巖的模量也增加,圍壓與模量之間近似為直線關繫;飽水度增加,砂巖模量降低,單軸下飽和砂巖的模量降低50.9%;飽水度與砂巖模量之間近似服從直線或負指數函數關繫。(2)飽水度增加,峰值彊度下降;單軸條件下飽和砂巖的峰值彊度下降瞭44.2%;飽水度與砂巖峰值彊度之間近似服從自然對數關繫。(3)彊度退化指數可以較好地描述圍壓對殘餘彊度的影響,巴裏坤砂巖的彊度退化指數與圍壓之間近似符閤負指數關繫;隨著飽水度增加,砂巖的殘餘彊度降低。(4)隨著圍壓增加,飽水度對砂巖模量、峰值彊度和殘餘彊度的影響都減弱。(5)飽水度在60%以下時,飽水度變化對模量和峰值彊度的影響顯著,噹飽水度超過60%後,模量和峰值彊度仍隨著飽水度增加而降低,但變化速率趨緩;對于殘餘彊度,則飽水度在80%以下時影響顯著。
위연구포수도화위압대사암역학특성적영향,재불동위압화포수도하개전삼축시험,획득료불동포수도화위압하파리곤사암적모량、봉치강도화잔여강도,분석료포수도화위압대사암모량、봉치강도화잔여강도적영향규률,결과표명:(1)위압증가,사암적모량야증가,위압여모량지간근사위직선관계;포수도증가,사암모량강저,단축하포화사암적모량강저50.9%;포수도여사암모량지간근사복종직선혹부지수함수관계。(2)포수도증가,봉치강도하강;단축조건하포화사암적봉치강도하강료44.2%;포수도여사암봉치강도지간근사복종자연대수관계。(3)강도퇴화지수가이교호지묘술위압대잔여강도적영향,파리곤사암적강도퇴화지수여위압지간근사부합부지수관계;수착포수도증가,사암적잔여강도강저。(4)수착위압증가,포수도대사암모량、봉치강도화잔여강도적영향도감약。(5)포수도재60%이하시,포수도변화대모량화봉치강도적영향현저,당포수도초과60%후,모량화봉치강도잉수착포수도증가이강저,단변화속솔추완;대우잔여강도,칙포수도재80%이하시영향현저。
To obtain the effects of varied saturations and confining pressures on mechanical properties of sandstone, the triaxial tests on sandstone samples from Balikun mine were performed under varied saturation and confining pressures. Then the modulus, peak strength and residual strength were obtained. The effects of varied saturations and confining pressures on mechanical properties of Balikun’s sandstone were analyzed; and the results show that: (1) With confining pressure increasing, the sandstone modulus increases, and the relationship between confining pressure and modulus follows linear form. With saturation increasing, the modulus decreases. The uniaxial compression modulus of saturated sandstone decreases 50.9%. The relationship between saturation and modulus follows linear or negative exponential form. (2) With saturation increasing, the peak strength decreases. The uniaxial compression strength of saturated sandstone decreases 44.2%.The relationship between saturation and peak strength follows natural logarithm form. (3) The effects of confining pressure on residual strength can be described by degradation index. The relationship between degradation index and confining pressure of Balikun sandstone follows negative exponential form. With saturation increasing, the residual strength decreases. (4) With confining pressure increasing, the effects of varied saturation on modulus, peak strength and residual strength decrease. (5) Less than 60%of saturation, variation of saturation greatly influences the modulus and peak strength. Larger than 60%, the effects decrease. Less than 80%of saturation, variation of saturation greatly influences residual strength.