【摘要】：尺寸效應是節(jié)理巖體力學性質(zhì)的重要特征,表征單元體(Representative Elementary Volume)是尺寸效應研究的核心內(nèi)容。本文圍繞巖體力學性質(zhì)的尺寸效應對節(jié)理巖體的變形參數(shù)與強度參數(shù)表征單元體REV及其分形特征進行了系統(tǒng)的研究,對合理選擇節(jié)理巖體的力學介質(zhì)模型與等效力學參數(shù)具有指導意義。主要內(nèi)容有：綜合采用數(shù)字攝影測量與數(shù)理統(tǒng)計技術,研究了不同分布形式的節(jié)理網(wǎng)絡模擬方法,并編制了相應的計算程序。實踐表明：該算法可以產(chǎn)生與研究區(qū)真實巖體結(jié)構(gòu)在統(tǒng)計上完全等效的節(jié)理網(wǎng)絡模型。采用RFPA2D數(shù)值分析軟件重點研究了節(jié)理巖體變形和強度參數(shù)的尺寸效應與各向異性,并得到不同力學參數(shù)的REV大小。數(shù)值試驗結(jié)果表明：研究區(qū)節(jié)理巖體的彈性模量B、剪切模量Gxy、單軸抗壓強度即均隨巖體試樣尺寸的增大而變化,表現(xiàn)出明顯的尺寸效應,當巖體試樣尺寸增大到一定值后,這些參數(shù)均趨于穩(wěn)定,并獲得了研究區(qū)節(jié)理巖體的等效柔度矩陣[C]及宏觀強度參數(shù)c、φ。綜合采用巖體節(jié)理網(wǎng)絡生成技術和數(shù)值分析方法,研究了巖體強度隨節(jié)理分布分維的變化關系及其破壞模式。研究表明：分形維數(shù)越小,節(jié)理在巖體試樣中分布越不均勻；節(jié)理巖體的單軸抗壓強度隨著分形維數(shù)的增大而增大；當節(jié)理巖體結(jié)構(gòu)滿足一定條件時,分形維數(shù)與巖體強度的關系也蘊含著尺寸效應的原理。
[Abstract]:Dimension effect is an important feature of mechanical properties of jointed rock mass, and the characterization of unit (Representative Elementary Volume) is the core of size effect research. Based on the size effect of mechanical properties of rock mass, the deformation and strength parameters of jointed rock mass are studied systematically in this paper. The REV and its fractal characteristics of the unit body are characterized by the parameters of deformation and strength of jointed rock mass. It is of guiding significance for the reasonable selection of mechanical medium model and equivalent mechanical parameters of jointed rock mass. The main contents are as follows: using digital photogrammetry and mathematical statistics technology, the paper studies the simulation method of joint network with different distribution forms, and compiles the corresponding calculation program. The practice shows that the proposed algorithm can produce a joint network model that is statistically equivalent to the real rock mass structure in the study area. The size effect and anisotropy of deformation and strength parameters of jointed rock mass are studied with RFPA2D numerical analysis software, and the REV values of different mechanical parameters are obtained. The numerical results show that the elastic modulus B and shear modulus Gxy, of jointed rock mass in the study area change with the increase of the specimen size, and show obvious size effect. When the specimen size increases to a certain value, the uniaxial compressive strength of the jointed rock mass changes with the size of the rock mass specimen. These parameters tend to be stable, and the equivalent flexibility matrix [C] and macroscopic strength parameters c, 蠁 of jointed rock mass in the study area are obtained. The variation of rock mass strength with the fractal dimension of joint distribution and its failure mode are studied by using the technique of rock mass joint network generation and numerical analysis. The results show that the smaller the fractal dimension, the more uneven the joint distribution in rock samples, and the greater the uniaxial compressive strength of jointed rock mass increases with the increase of fractal dimension. When the structure of jointed rock mass meets certain conditions, the relationship between fractal dimension and rock mass strength also implies the principle of size effect.
【學位授予單位】：大連理工大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TU45

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本文編號：2335892