發(fā)布時間：2018-06-05 16:56

  本文選題：透明土 + 透明度��； 參考：《浙江大學》2017年碩士論文

【摘要】：透明土是由透明固體顆粒及與其折射率相匹配的透明孔隙流體所組成的兩相介質(zhì)。其中,透明的固體顆粒、孔隙流體分別代表了天然的土顆粒、孔隙流體的各類特性。因此,透明土被廣泛地應(yīng)用于土工試驗中對天然土體的巖土力學特性的模擬。迄今為止,不同學者采用不同的配方配置了不同特性的透明土,各類透明土均可在一定程度上有效地模擬天然土體的物理力學特性�；谕该魍翆μ烊煌馏w的有效模擬,可對土體內(nèi)部進行非介入式、無損和連續(xù)的測量,相比于巖土工程傳統(tǒng)測量方法可避免傳感器剛度、尺寸等對試驗結(jié)果的干擾,能更全面地觀測到內(nèi)部的土顆粒的運動特征,同時相比于X射線掃描和核磁共振等其它非介入式測量方法,透明土測量更經(jīng)濟、直觀且易于操作。在透明土可視化實驗技術(shù)中,數(shù)字圖像采用DIC(DigitalImageCorrelation,數(shù)字圖像相關(guān)方法)進行數(shù)據(jù)處理。鑒于成像質(zhì)量及DIC分析的準確性均與透明的透明度有關(guān),因此本文針對透明土的透明度提出了參數(shù)化的客觀評價方法。在總結(jié)國內(nèi)外研究的基礎(chǔ)上,以熔融石英砂作為透明土的固體顆粒,以白礦物油和溶劑油的混合物作為孔隙流體,從而配置了熔融石英砂透明土,并在本文中對透明土的透明度及其對可視化實驗技術(shù)的影響進行了如下研究:(1)基于光度學原理定義的透射率來定量評價透明土的透明度。首先提出了透射率的計算原理及測量方法,進一步通過克里斯欣森效應(yīng)的規(guī)律研究了固液折射率匹配程度和透光厚度對透明土透射率變化的影響,并發(fā)現(xiàn)了透明土中氣泡對提高透射率的不利作用。(2)探究了透明土的透明度對可視化實驗技術(shù)的影響:一方面,將熔融石英砂透明土透射率測量結(jié)果與相應(yīng)透明度效果圖的清晰度評價函數(shù)相關(guān)聯(lián),建立了透明土的透明度與可視化實驗技術(shù)中成像質(zhì)量的聯(lián)系;另一方面,通過標定不同透射率的透明土其DIC測量的精度,揭示了透明土的透明度與DIC測量精度間的關(guān)系。試驗發(fā)現(xiàn),透明土的透明土對DIC分析精度具有雙重影響,一方面透明度提高有利于提高數(shù)值圖像的清晰度,從而提高DIC分析的精度;另一方面,透明度提高削弱了“濾波”作用,從而有降低了 DIC分析的精度。
[Abstract]:Transparent soil is a two-phase medium composed of transparent solid particles and transparent pore fluid matching its refractive index. Among them, transparent solid particles and pore fluids represent various properties of natural soil particles and pore fluids, respectively. Therefore, transparent soil is widely used in geotechnical tests to simulate the geotechnical properties of natural soil. Up to now, different scholars have used different formulations to configure transparent soil with different properties, and all kinds of transparent soil can effectively simulate the physical and mechanical properties of natural soil to a certain extent. Based on the effective simulation of transparent soil to natural soil, non-interventional, non-destructive and continuous measurement can be carried out on the soil body. Compared with the traditional geotechnical engineering measurement method, the interference of sensor stiffness and size on the test results can be avoided. Compared with other non-interventional measurement methods such as X-ray scanning and nuclear magnetic resonance (NMR), the measurement of transparent soil is more economical, intuitive and easy to operate than that of other non-interventional measurement methods such as X-ray scanning and nuclear magnetic resonance. In the experiment technology of transparent soil visualization, the digital image is processed by DIC-Digital Image correlation (DIC-Digital Image correlation). Since the imaging quality and the accuracy of DIC analysis are related to the transparency of the transparent soil, a parameterized objective evaluation method for the transparency of the transparent soil is proposed in this paper. On the basis of summing up the research at home and abroad, the fused quartz sand is used as the solid particle of transparent soil, and the mixture of white mineral oil and solvent oil is used as pore fluid. In this paper, the transparency of transparent soil and its influence on visual experimental technology are studied as follows: 1) the transparency of transparent soil is quantitatively evaluated based on the transmittance defined by photometric principle. Firstly, the calculation principle and measurement method of transmittance are put forward, and the influence of the matching degree of refractive index of solid and liquid and the thickness of transmittance on the change of transmittance of transparent soil is studied by the law of Christensen effect. The adverse effect of bubbles on increasing transmittance in transparent soil is found. (2) the influence of transparency of transparent soil on visual experimental technology is explored: on the one hand, In this paper, the relation between the transparency of fused quartz sand and the imaging quality in visual experiment is established by correlating the measurement results of transparent soil with the clarity evaluation function of the corresponding transparency effect diagram; on the other hand, the relationship between the transparency of the transparent soil and the imaging quality in the visualization experiment is established. The relationship between the transparency of transparent soil and the accuracy of DIC measurement is revealed by calibrating the accuracy of DIC measurement of transparent soil with different transmittance. It is found that the transparent soil of the transparent soil has a double influence on the accuracy of DIC analysis. On the one hand, the increase of transparency is conducive to the improvement of the clarity of the numerical image, thereby improving the accuracy of the DIC analysis; on the other hand, The improvement of transparency weakens the function of filtering and thus reduces the accuracy of DIC analysis.
【學位授予單位】：浙江大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TU43

【參考文獻】

相關(guān)期刊論文 前10條

1 周俊宏;宮全美;周順華;韓高孝;;盾構(gòu)隧道抬升作用下極限上覆土壓力計算方法[J];巖土力學;2016年07期

2 高岳;王檔良;;化學注漿防治立井二次涌水透明土試驗研究[J];煤炭科學技術(shù);2016年06期

3 周俊宏;宮全美;周順華;;基于透明土的隧道上浮過程結(jié)構(gòu)與土相互作用模型試驗[J];華東交通大學學報;2016年03期

4 孔綱強;曹兆虎;孫學謹;趙紅華;;負摩阻力作用下透明土中管樁中性點位置模型試驗[J];鐵道科學與工程學報;2016年05期

5 吳躍東;羅如平;劉堅;楊冬;;基于透明土的取土管貫入擾動變形試驗研究[J];巖土工程學報;2016年08期

6 孔綱強;曹兆虎;周航;丁選明;;水平荷載下擴底楔形樁承載力特性透明土模型試驗[J];土木工程學報;2015年05期

7 齊昌廣;陳永輝;王新泉;左殿軍;;細長樁屈曲的透明土物理模型試驗研究[J];巖石力學與工程學報;2015年04期

8 張儀萍;李亮;王思照;;透明土中孔隙流體的實驗研究[J];浙江大學學報(工學版);2014年10期

9 曹兆虎;孔綱強;劉漢龍;周航;;基于透明土的管樁貫入特性模型試驗研究[J];巖土工程學報;2014年08期

10 曹兆虎;孔綱強;劉漢龍;周航;;基于透明土材料的沉樁過程土體三維變形模型試驗研究[J];巖土工程學報;2014年02期

相關(guān)博士學位論文 前2條

1 高越;三維數(shù)字圖像相關(guān)法的關(guān)鍵技術(shù)及應(yīng)用研究[D];中國科學技術(shù)大學;2014年

2 孟利波;數(shù)字散斑相關(guān)方法的研究和應(yīng)用[D];清華大學;2005年

相關(guān)碩士學位論文 前7條

1 高炳倫;基于透明土的采掘潰砂流動形態(tài)試驗研究[D];中國礦業(yè)大學;2015年

2 李文濤;基于人工合成透明土盾構(gòu)隧道壁后同步注漿模型試驗研究[D];北京交通大學;2015年

3 常艷;基于透明土技術(shù)的帶承臺單樁豎向荷載作用下的土體二維變形研究[D];大連理工大學;2015年

4 李亮;透明土合成及物理力學特性研究[D];浙江大學;2014年

5 陳振英;基于數(shù)字圖像相關(guān)法的應(yīng)變測量研究[D];上海交通大學;2013年

6 劉佳佳;基于透明土的盾構(gòu)隧道開挖面穩(wěn)定性分析[D];武漢理工大學;2012年

7 吳明喜;人工合成透明砂土及其三軸試驗研究[D];大連理工大學;2006年

，

本文編號：1982749