【摘要】：隨著我國經(jīng)濟建設(shè)的高速發(fā)展,基礎(chǔ)建設(shè)與資源開采的規(guī)模不斷擴大,隨之也面臨著大量的工程地質(zhì)難題。尤其是在石灰石礦山的開采過程中,往往會形成大規(guī)模、工程地質(zhì)條件復雜的高邊坡。往往也正是由組成高邊坡的節(jié)理巖體決定了礦山高邊坡的穩(wěn)定性。節(jié)理巖體是由結(jié)構(gòu)面與完整巖石組合而成的復雜綜合體。正是節(jié)理巖體結(jié)構(gòu)的復雜性決定了其力學性質(zhì)的非均勻、非線性和各向異性。節(jié)理巖體的強度特性不僅受其內(nèi)部巖石與結(jié)構(gòu)面強度的影響,同時也受到結(jié)構(gòu)面不同組合形式對強度的劣化作用。對節(jié)理巖體結(jié)構(gòu)特征及強度參數(shù)的研究是進行巖體工程力學性質(zhì)評價與穩(wěn)定性分析的重要環(huán)節(jié)。本文以峨勝石灰石礦山露采高邊坡巖體為研究對象,對節(jié)理巖體強度參數(shù)特性進行了系統(tǒng)研究。在野外工程地質(zhì)調(diào)查與地質(zhì)資料收集統(tǒng)計的基礎(chǔ)上,結(jié)合三維離散元數(shù)值計算方法和經(jīng)驗估算方法,對節(jié)理巖體強度參數(shù)的尺寸效應(yīng)與各向異性進行了探討,并對巖體工程中合理選取節(jié)理巖體強度參數(shù)提供了參考。本文的研究內(nèi)容如下:(1)對研究區(qū)進行工程地質(zhì)調(diào)查與分析,進一步以巖體結(jié)構(gòu)差異對研究區(qū)進行分區(qū)。采用測線法對每個區(qū)進行現(xiàn)場結(jié)構(gòu)面測量與統(tǒng)計。Ⅰ區(qū)測量結(jié)構(gòu)面50條,含優(yōu)勢結(jié)構(gòu)面一組;Ⅱ區(qū)測量結(jié)構(gòu)面106條,含優(yōu)勢結(jié)構(gòu)面兩組;Ⅲ區(qū)測量結(jié)構(gòu)面323條,含優(yōu)勢結(jié)構(gòu)面四組。(2)結(jié)合圖解法和改進的快速聚類分析法,對各區(qū)優(yōu)勢結(jié)構(gòu)面進行了統(tǒng)計分組。進一步采用概率圖法得出了對各區(qū)結(jié)構(gòu)面的幾何特征參數(shù)的概率分布類型。結(jié)果顯示結(jié)構(gòu)面傾向和傾角大部分符合正態(tài)分布規(guī)律,少數(shù)符合均勻分布。結(jié)構(gòu)面間距和半跡長則符合負指數(shù)分布規(guī)律。(3)以結(jié)構(gòu)面幾何分布概率模型為基礎(chǔ),結(jié)合蒙特卡洛法與Fish編程語言實現(xiàn)了在3DEC軟件中三維結(jié)構(gòu)面網(wǎng)絡(luò)模型的建立。分析各區(qū)網(wǎng)絡(luò)模型可知,其中一區(qū)巖體結(jié)構(gòu)完整性好,僅受巖層面切割。二區(qū)受兩組互相垂直節(jié)理切割,巖體呈塊狀結(jié)構(gòu)。三區(qū)巖體受四組優(yōu)勢結(jié)構(gòu)面切割,巖體完整性較差。(4)在三維結(jié)構(gòu)面網(wǎng)絡(luò)模型基礎(chǔ)上,進一步實現(xiàn)了三種巖體結(jié)構(gòu)下的等圍壓三軸數(shù)值試驗,其中對于隨機節(jié)理巖體模型采用了DFN裂隙網(wǎng)絡(luò)模型和蒙特卡羅法相結(jié)合,使數(shù)值計算能夠比較真實的模擬實際巖體的受力狀態(tài)。對巖體強度參數(shù)的各向異性和尺寸效應(yīng)進行了研究。結(jié)果表明不同巖體結(jié)構(gòu)的巖體其尺寸效應(yīng)和各向異性也不同。受結(jié)構(gòu)面切割程度越高,巖體尺寸效應(yīng)趨于明顯,而各向異性會相對減弱。(5)結(jié)合離散元數(shù)值計算結(jié)果、RMR評分系統(tǒng)和GSI評分系統(tǒng)下Hoek-Brown強度準則對研究區(qū)節(jié)理巖體強度參數(shù)進行估算。結(jié)果顯示三種方法得出的巖體強度參數(shù)中,RMR評分系統(tǒng)最小、GSI評分系統(tǒng)中等,離散元數(shù)值方法最大。
[Abstract]:With the rapid development of economic construction in China, the scale of infrastructure construction and resource exploitation is expanding constantly, and a large number of engineering geological problems are also faced with. Especially in the process of limestone mining, large-scale, complex engineering geological conditions will often form a high slope. The stability of mine high slope is often determined by the jointed rock mass which is composed of high slope. Jointed rock mass is a complex composed of structural plane and intact rock. It is the complexity of jointed rock mass structure that determines the non-uniformity, nonlinearity and anisotropy of its mechanical properties. The strength characteristics of jointed rock mass are not only affected by the strength of the internal rock and the structural plane, but also by the deterioration of the strength of the jointed rock mass by different combination forms of the structural plane. The research on the structural characteristics and strength parameters of jointed rock mass is an important link in the evaluation and stability analysis of rock mass engineering mechanical properties. In this paper, the strength parameter characteristics of jointed rock mass are studied systematically by taking the open-pit high slope rock mass of Esheng limestone mine as the research object. On the basis of field engineering geological survey and geological data collection statistics, combined with three-dimensional discrete element numerical calculation method and empirical estimation method, the size effect and anisotropy of strength parameters of jointed rock mass are discussed. It also provides a reference for reasonable selection of strength parameters of jointed rock mass in rock mass engineering. The research contents of this paper are as follows: (1) the engineering geological investigation and analysis are carried out in the study area, and the difference of rock mass structure is further used to divide the study area. The field structural planes of each area were measured and counted by the method of measurement. 50 structural planes were measured in area 鈪，

本文編號：2458954