岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
3期
666-674
,共9页
张玉%徐卫亚%赵海斌%王伟%梅松华
張玉%徐衛亞%趙海斌%王偉%梅鬆華
장옥%서위아%조해빈%왕위%매송화
岩石力学%碎屑砂岩%试验研究%强度%变形
巖石力學%碎屑砂巖%試驗研究%彊度%變形
암석역학%쇄설사암%시험연구%강도%변형
rock mechanics%clastic sandstone%experimental investigation%strength%deformation
基于碎屑岩组织结构疏松、含水率较高、物理力学性能较差、呈孔隙式胶结接触等特点,对碎屑砂岩首先开展了物理特性试验分析,认为其微、细观结构复杂、内部破坏严重,矿物成分为石英、长石、绢云母等,化学成分以 SiO2为主,属微透水、小孔隙率砂岩,且渗水化学侵蚀并不显著。其次,开展了静水压力、单轴压缩和三轴压缩试验,研究了碎屑砂岩的强度和变形破坏特性。最后,初步探索了物理特性与强度变形特性的关系。结果表明,静水压力为2.6 MPa时,岩样内部微缺陷压密完成;单轴压缩曲线呈明显6阶段特征,峰值应力达0.98 MPa,属脆-延性破坏;三轴压缩条件下,岩样呈压缩为主的延性扩容破坏,轴向压缩和环向体积扩容达6%和4%;曲线无明显破坏荷载,呈现非线性、塑性硬化、存在屈服平台和体积由压缩向扩容过渡等特性。且体积扩容破损应力与屈服应力基本相同,扩容转折点随围压增加而增大,围压可增强岩样抵抗变形破坏的能力。试验结果旨在为岩石工程稳定分析及本构模型构建提供可靠的依据。
基于碎屑巖組織結構疏鬆、含水率較高、物理力學性能較差、呈孔隙式膠結接觸等特點,對碎屑砂巖首先開展瞭物理特性試驗分析,認為其微、細觀結構複雜、內部破壞嚴重,礦物成分為石英、長石、絹雲母等,化學成分以 SiO2為主,屬微透水、小孔隙率砂巖,且滲水化學侵蝕併不顯著。其次,開展瞭靜水壓力、單軸壓縮和三軸壓縮試驗,研究瞭碎屑砂巖的彊度和變形破壞特性。最後,初步探索瞭物理特性與彊度變形特性的關繫。結果錶明,靜水壓力為2.6 MPa時,巖樣內部微缺陷壓密完成;單軸壓縮麯線呈明顯6階段特徵,峰值應力達0.98 MPa,屬脆-延性破壞;三軸壓縮條件下,巖樣呈壓縮為主的延性擴容破壞,軸嚮壓縮和環嚮體積擴容達6%和4%;麯線無明顯破壞荷載,呈現非線性、塑性硬化、存在屈服平檯和體積由壓縮嚮擴容過渡等特性。且體積擴容破損應力與屈服應力基本相同,擴容轉摺點隨圍壓增加而增大,圍壓可增彊巖樣牴抗變形破壞的能力。試驗結果旨在為巖石工程穩定分析及本構模型構建提供可靠的依據。
기우쇄설암조직결구소송、함수솔교고、물리역학성능교차、정공극식효결접촉등특점,대쇄설사암수선개전료물리특성시험분석,인위기미、세관결구복잡、내부파배엄중,광물성분위석영、장석、견운모등,화학성분이 SiO2위주,속미투수、소공극솔사암,차삼수화학침식병불현저。기차,개전료정수압력、단축압축화삼축압축시험,연구료쇄설사암적강도화변형파배특성。최후,초보탐색료물리특성여강도변형특성적관계。결과표명,정수압력위2.6 MPa시,암양내부미결함압밀완성;단축압축곡선정명현6계단특정,봉치응력체0.98 MPa,속취-연성파배;삼축압축조건하,암양정압축위주적연성확용파배,축향압축화배향체적확용체6%화4%;곡선무명현파배하재,정현비선성、소성경화、존재굴복평태화체적유압축향확용과도등특성。차체적확용파손응력여굴복응력기본상동,확용전절점수위압증가이증대,위압가증강암양저항변형파배적능력。시험결과지재위암석공정은정분석급본구모형구건제공가고적의거。
Based on the characteristics of loose organizational structure, high moisture content, poor physical mechanical properties and pore cementation contact, the basic physical properties tests on clastic sandstone were carried out first. It's considered that the rock which belongs to small porosity sandstone as micro-permeability is extremely complex microstructure and that internal structure is damage seriously. The main mineral compositions are quartz, feldspar, sericite and so on;mainly chemical constituent is SiO2 and the chemical erosion is not significant. Secondly, the hydrostatic pressure tests, uniaxial and triaxial compression tests were carried out for clastic sandstone to study the strength and deformation failure properties. Finally, the correlations between mechanical properties and physical properties are preliminary discussed. The results show that the internal micro-defect of rock is compaction completed when hydrostatic pressure reaches 2.6 MPa. The uniaxial compression curve shows the characteristics of six distinct stages;and that the peak stress is 0.98 MPa. Moreover, brittleness and ductility are shown. Under triaxial compression test, clastic rock shows significant characteristics of mainly compressed and ductility dilatancy failure. In the action of deviatoric stress, the axial and lateral strains of rock reach 6% and 4% respectively. The curve has no significant damage load, which shows the mechanical properties of nonlinear, plastic hardening, yield platform and volume strain from compression to ductility dilatancy and so on. And the volume dilatancy damage stress is almost the same as the yield stress. The dilatancy turning point increases with an increase of confining pressure, and moreover, the confining pressure enhances the rock resistance to deformation and failure. The results provide dependable reference for the establishment of rock constitutive model and stability analysis.