發(fā)布時(shí)間：2018-06-25 10:17

  本文選題：顆粒形狀 + 形狀參數(shù)　； 參考：《長(zhǎng)江科學(xué)院》2015年碩士論文

【摘要】：多孔介質(zhì)是由固體構(gòu)成復(fù)雜孔隙系統(tǒng)的骨架,流體可以在其內(nèi)部連通的孔隙系統(tǒng)運(yùn)動(dòng)的物質(zhì)空間。最常見且為人們廣泛利用的多孔介質(zhì)固體材料為人工爆破碎石料或經(jīng)過(guò)長(zhǎng)距離搬運(yùn)的砂礫石,所以研究顆粒形狀對(duì)于多孔介質(zhì)孔隙系統(tǒng)和滲透特性的影響,具有重要實(shí)際意義。本文研究顆粒形狀的測(cè)量途徑和評(píng)價(jià)方法,采用影像測(cè)量?jī)x和專門研制的夾具,利用5個(gè)形狀參數(shù)對(duì)三組粒徑的顆粒形狀進(jìn)行測(cè)量和評(píng)定。通過(guò)利用CT機(jī)掃描獲取的掃描斷面圖,在不同開度閾值下統(tǒng)計(jì)分析了碎石料填筑試樣和玻璃球填筑試樣孔隙大小分布規(guī)律,以及孔隙形狀分形特征。通過(guò)碎石料和玻璃球填筑試樣的滲透試驗(yàn),初步分析探討了顆粒形狀對(duì)多孔介質(zhì)滲透特性的影響規(guī)律。本文的主要研究?jī)?nèi)容和結(jié)論如下:(1)采用影像測(cè)量?jī)x和專用夾具多角度量測(cè)碎石顆粒形狀,豐富了顆粒形狀測(cè)量信息,為更準(zhǔn)確地評(píng)定顆粒形狀奠定了基礎(chǔ)。(2)采用5個(gè)形狀參數(shù)評(píng)定顆粒形狀。統(tǒng)計(jì)分析了三個(gè)粒徑組顆粒群的形狀參數(shù)分布規(guī)律,獲取顆粒形狀參數(shù)的分布特征,比較碎石顆粒與標(biāo)準(zhǔn)球體形狀的差異。通過(guò)形狀參數(shù)的對(duì)比,指出長(zhǎng)寬比、扁平度和球形度能夠較敏感地反映顆粒偏離球體的程度,其中,相對(duì)于扁平度來(lái)說(shuō),長(zhǎng)寬比、球形度的獲取更方便和直接,因而在可操作性和效率上更具優(yōu)勢(shì)。(3)利用CT機(jī)掃描獲取碎石料和玻璃球填筑試樣的斷面圖,發(fā)現(xiàn)其內(nèi)部的孔隙形態(tài)都很復(fù)雜,所選粒徑組試樣CT掃描二維圖像上顯示了較好的連通性。采用合適的孔隙開度閾值,可以在狹窄處斷開孔隙,以便開展孔隙大小統(tǒng)計(jì)分析和分形特征研究。(4)針對(duì)同一粒組同一粒徑分布的碎石顆粒和玻璃球填筑試樣,可以開展?jié)B透性對(duì)比試驗(yàn),初步結(jié)果表明,顆粒形狀越不規(guī)則,滲透系數(shù)越大。
[Abstract]:Porous media is a material space in which a complex porous system is composed of solids, in which fluid can move through a connected pore system. The most common and widely used solid material in porous media is artificial blasting gravel or sand gravel which is transported over long distances. So it is of great practical significance to study the influence of particle shape on pore system and permeability characteristics of porous media. In this paper, the measurement and evaluation methods of particle shape are studied. The shape of three groups of particle size is measured and evaluated by using the image measuring instrument and the specially developed fixture, using five shape parameters. The pore size distribution law and fractal characteristics of pore shape of gravel filled specimen and glass ball filled specimen were statistically analyzed under different opening threshold by using scanning sectional diagram obtained by CT scanning. The influence of particle shape on permeability characteristics of porous media was preliminarily analyzed through the permeation test of gravel and glass ball filled samples. The main contents and conclusions of this paper are as follows: (1) the shape of crushed stone is measured by image measuring instrument and special fixture, which enriches the information of particle shape measurement. It lays a foundation for more accurate evaluation of particle shape. (2) five shape parameters are used to evaluate particle shape. The distribution rules of shape parameters of three particle groups were statistically analyzed, and the distribution characteristics of particle shape parameters were obtained, and the differences between gravel particles and standard spheres were compared. Through the comparison of shape parameters, it is pointed out that the aspect ratio, flatness and sphericity can more sensitively reflect the degree of particle deviation from the sphere, and the ratio of length to width is more convenient and direct to obtain the spherical degree than the flatness. Therefore, it has more advantages in maneuverability and efficiency. (3) using CT scanning to obtain the fracture diagrams of gravel and glass-filled specimens, it is found that the internal pore morphology is very complex. The two-dimensional CT images of the selected particle size groups showed good connectivity. With the appropriate pore opening threshold, the pores can be disconnected in the narrow area for the purpose of statistical analysis of pore size and study of fractal characteristics. (4) for the sample filled with crushed stone and glass ball with the same particle group and the same size distribution, The preliminary results show that the more irregular the particle shape, the greater the permeability coefficient.
【學(xué)位授予單位】：長(zhǎng)江科學(xué)院
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TU411

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 張家發(fā);定培中;張偉;胡智京;;水布埡面板堆石壩過(guò)渡料設(shè)計(jì)及其滲透變形特性研究[J];長(zhǎng)江科學(xué)院院報(bào);2009年10期

2 穆在勤,龍期威;由面積-周長(zhǎng)關(guān)系測(cè)量的分形維數(shù)與材料韌性的關(guān)系[J];材料科學(xué)進(jìn)展;1989年02期

3 施斌;粘性土微觀結(jié)構(gòu)研究回顧與展望[J];工程地質(zhì)學(xué)報(bào);1996年01期

4 陳江峰,王振芬,閆純忠;碎屑顆粒圓度的分形描述[J];煤田地質(zhì)與勘探;2002年04期

5 劉杰;混凝土面板壩碎石墊層料最佳級(jí)配試驗(yàn)研究[J];水利水運(yùn)工程學(xué)報(bào);2001年04期

6 陳云波,徐培濤;水泥顆粒形貌的表征及其研究方法[J];水泥;2003年02期

7 周健;姚志雄;白彥峰;張姣;;砂土管涌的細(xì)觀機(jī)理研究[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);2008年06期

8 周健;楊永香;劉洋;;飽和砂土液化過(guò)程中細(xì)觀組構(gòu)的模型試驗(yàn)研究[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);2009年04期

9 周健;姚志雄;張剛;;基于散體介質(zhì)理論的砂土管涌機(jī)制研究[J];巖石力學(xué)與工程學(xué)報(bào);2008年04期

10 周偉;常曉林;周創(chuàng)兵;朱開祥;;堆石體應(yīng)力變形細(xì)觀模擬的隨機(jī)散粒體不連續(xù)變形模型及其應(yīng)用[J];巖石力學(xué)與工程學(xué)報(bào);2009年03期

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本文編號(hào)：2065577