【摘要】：水-巖相互作用是工程巖土體穩(wěn)定性研究的重要內(nèi)容,近年來一直是巖土工程相關(guān)學(xué)科研究的前沿領(lǐng)域。本文依托導(dǎo)師國家自然科學(xué)基金項目(No.41202229)“干濕交替作用下泥質(zhì)砂巖強度劣化機理及損傷本構(gòu)關(guān)系研究”,以云南某露天礦邊坡砂巖為研究對象,以自然條件下砂巖干濕循環(huán)效應(yīng)與微觀結(jié)構(gòu)發(fā)展演化規(guī)律為研究目的,通過室內(nèi)砂巖強度、變形試驗和微觀測試,獲取了干濕交替作用下砂巖強度和變形的變化規(guī)律,并從微觀角度探討了其產(chǎn)生干濕循環(huán)效應(yīng)的作用機制,主要研究成果如下： (1)通過粉晶X衍射、薄片鑒定等手段測定了砂巖的礦物組成及含量；對干濕交替作用下的砂巖試樣進行了吸水性試驗,結(jié)果表明砂巖吸水率隨干濕循環(huán)幅度的加大而增加,并建立了其與干濕循環(huán)次數(shù)之間的函數(shù)關(guān)系。 (2)對設(shè)定試驗點的砂巖試樣進行了單軸壓縮變形試驗,得到了砂巖在不同狀態(tài)下的應(yīng)力應(yīng)變?nèi)^程曲線、抗壓強度及變形指標,并對其隨干濕循環(huán)次數(shù)的變化情況進行了系統(tǒng)的分析。 (3)進行了各關(guān)鍵試驗點砂巖試樣在單軸壓縮變形下的聲發(fā)射特征試驗,結(jié)果表明,砂巖在干燥狀態(tài)下的聲發(fā)射活動較經(jīng)干濕循環(huán)處理后要強烈的多,且隨干濕循環(huán)次數(shù)的加大,聲發(fā)射活動逐步減弱,同時產(chǎn)生了明顯聲發(fā)射的時間滯后現(xiàn)象。 (4)基于單軸壓縮變形試驗結(jié)果建立了考慮干濕循環(huán)效應(yīng)砂巖的損傷統(tǒng)計本構(gòu)關(guān)系,并對其進行了驗證,結(jié)果表明所構(gòu)建考慮干濕循環(huán)效應(yīng)砂巖的損傷統(tǒng)計本構(gòu)模型是合理的。 (5)開展了不同干濕循環(huán)作用下砂巖試樣的直剪試驗,試驗結(jié)果表明砂巖抗剪強度與所受法向應(yīng)力呈正相關(guān)關(guān)系,與干濕循環(huán)次數(shù)呈負相關(guān)關(guān)系,砂巖抗剪強度參數(shù)隨干濕循環(huán)作用幅度的加大而降低,且粘聚力c對干濕循環(huán)效應(yīng)的響應(yīng)程度較內(nèi)摩擦角φ要大。 (6)從微觀角度出發(fā),通過偏光顯微鏡觀測不同狀態(tài)砂巖試樣內(nèi)部孔隙結(jié)構(gòu)、顆粒膠結(jié)方式等的變化情況。分析表明其內(nèi)部結(jié)構(gòu)隨干濕循環(huán)幅度的加大亦有相應(yīng)的改變。
[Abstract]:Water-rock interaction is an important part of the stability of rock and soil in engineering, and has been the frontier of geotechnical engineering in recent years. In this paper, based on the project of National Natural Science Foundation of China (No.41202229), "study on strength deterioration mechanism and damage constitutive relationship of argillaceous sandstone under dry-wet alternating action", a slope sandstone of an open-pit mine in Yunnan Province is taken as the research object. In order to study the dry-wet cycle effect and microstructure evolution law of sandstone under natural conditions, the variation law of sandstone strength and deformation under the alternating action of dry and wet is obtained through indoor sandstone strength, deformation test and microscopic test. The main results are as follows: (1) the mineral composition and content of sandstone were determined by powder X-ray diffraction and thin slice identification. The water absorption test of sandstone samples under the alternating action of dry and wet is carried out. The results show that the water absorption rate of sandstone increases with the increase of dry-wet cycle amplitude. The relationship between the number of dry and wet cycles is established. (2) uniaxial compression deformation tests are carried out on sandstone samples with set test points, and the stress-strain curves of sandstone under different conditions are obtained. The compressive strength and deformation index are systematically analyzed. (3) the acoustic emission characteristics of sandstone samples under uniaxial compression deformation at key test points are studied. The acoustic emission activity of sandstone in dry state is much stronger than that after dry and wet cycle treatment, and with the increase of dry and wet cycle times, the acoustic emission activity gradually weakens. At the same time, the time-lag phenomenon of acoustic emission is obvious. (4) based on the results of uniaxial compression deformation test, the statistical constitutive relationship of damage of sandstone considering dry-wet cycle effect is established and verified. The results show that the statistical constitutive model of sandstone damage considering dry-wet cycle effect is reasonable. (5) the direct shear tests of sandstone samples under different dry and wet cycles are carried out. The test results show that the shear strength of sandstone is positively correlated with the normal stress, and negatively correlated with the times of dry and wet cycles. The shear strength parameters of sandstone decrease with the increase of dry-wet cycle. The cohesive force c is more responsive to the dry and wet cycle effect than the internal friction angle 蠁. (6) from the microscopic point of view, the changes of pore structure and particle cementation mode of sandstone samples in different states are observed by polarizing microscope. The analysis shows that the internal structure changes with the increase of dry-wet cycle amplitude.
【學(xué)位授予單位】：昆明理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TU45

【參考文獻】

相關(guān)期刊論文 前10條

1 劉明維,傅華,吳進良;巖體結(jié)構(gòu)面抗剪強度參數(shù)確定方法的現(xiàn)狀及思考[J];重慶交通學(xué)院學(xué)報;2005年05期

2 劉明維,何沛田,錢志雄,鄭穎人;巖體結(jié)構(gòu)面抗剪強度參數(shù)試驗研究[J];重慶建筑;2005年06期

3 徐濤,唐春安,張哲,張永彬;單軸壓縮條件下脆性巖石變形破壞的理論、試驗與數(shù)值模擬[J];東北大學(xué)學(xué)報;2003年01期

4 陳鋼林,周仁德;水對受力巖石變形破壞宏觀力學(xué)效應(yīng)的實驗研究[J];地球物理學(xué)報;1991年03期

5 K.Masuda;O.Nishizawa;K.Kusunose;T.Satoh;劉希強;;原地地應(yīng)力狀態(tài)和巖石強度對流體誘發(fā)地震活動影響的實驗室研究[J];世界地震譯叢;1995年02期

6 劉軍忠;許金余;呂曉聰;王澤東;張磊;;圍壓下巖石的沖擊力學(xué)行為及動態(tài)統(tǒng)計損傷本構(gòu)模型研究[J];工程力學(xué);2012年01期

7 楊圣奇,徐衛(wèi)亞,韋立德,蘇承東;單軸壓縮下巖石損傷統(tǒng)計本構(gòu)模型與試驗研究[J];河海大學(xué)學(xué)報(自然科學(xué)版);2004年02期

8 曾勝;李振存;陳涵杰;趙健;;干濕循環(huán)下紅砂巖強度衰減規(guī)律及工程應(yīng)用[J];長沙理工大學(xué)學(xué)報(自然科學(xué)版);2011年04期

9 謝強,張永興,余賢斌;石灰?guī)r在單軸壓縮條件下的聲發(fā)射特性[J];重慶建筑大學(xué)學(xué)報;2002年01期

10 謝和平;大理巖微觀斷裂的分形(fractal)模型研究[J];科學(xué)通報;1989年05期

相關(guān)博士學(xué)位論文 前1條

1 傅晏;干濕循環(huán)水巖相互作用下巖石劣化機理研究[D];重慶大學(xué);2010年

，

本文編號：2167419