本文選題：黃土節(jié)理 + 剪切強(qiáng)度�。� 參考：《西安建筑科技大學(xué)》2017年碩士論文

【摘要】：黃土節(jié)理的剪切強(qiáng)度特性對(duì)于含節(jié)理黃土工程的穩(wěn)定性有重要影響,而節(jié)理剪切強(qiáng)度特性與節(jié)理表面形態(tài)密切相關(guān)。為此,需對(duì)節(jié)理表面形態(tài)進(jìn)行了研究。首先,在大量野外調(diào)研的基礎(chǔ)上,選取合適場(chǎng)地采集了天然黃土節(jié)理試樣,利用輪廓曲線儀測(cè)量節(jié)理表面形態(tài),并繪制了節(jié)理面輪廓曲線。運(yùn)用統(tǒng)計(jì)學(xué)方法計(jì)算了節(jié)理表面特征參數(shù),然后選取高度均方根z1、峰點(diǎn)密度η、坡度均方根z2三個(gè)參數(shù),根據(jù)數(shù)據(jù)統(tǒng)計(jì)結(jié)果及經(jīng)驗(yàn)確定單因素分級(jí)范圍,利用模糊數(shù)學(xué)方法綜合評(píng)價(jià)節(jié)理表面形態(tài),最終得到了所取天然黃土節(jié)理試樣表面形態(tài)的綜合特征參數(shù)RJ及分級(jí)結(jié)果。依據(jù)節(jié)理表面形態(tài)分級(jí)標(biāo)準(zhǔn)制備試樣,采用室內(nèi)小型直剪試驗(yàn)方法研究了含水量對(duì)黃土節(jié)理剪切強(qiáng)度參數(shù)的影響規(guī)律,并對(duì)比室內(nèi)大型直剪試驗(yàn)與小型直剪試驗(yàn)結(jié)果,研究了尺寸效應(yīng)對(duì)剪切強(qiáng)度的影響,根據(jù)所有試驗(yàn)結(jié)果研究了節(jié)理剪切應(yīng)力-位移關(guān)系曲線特征。節(jié)理表面形態(tài)研究發(fā)現(xiàn)：不同場(chǎng)地間天然黃土土樣的節(jié)理表面形態(tài)存在差異,同一場(chǎng)地,節(jié)理表面形態(tài)相近;各節(jié)理面的峰態(tài)系數(shù)K值的范圍為2~3,均值接近3,表明節(jié)理面的全坐標(biāo)高度分布為高斯分布或準(zhǔn)高斯分布;驗(yàn)證發(fā)現(xiàn)RJ與節(jié)理剪切強(qiáng)度具有較好的線性相關(guān)性,說(shuō)明本次對(duì)節(jié)理面分級(jí)的方法具有可行性。直剪試驗(yàn)結(jié)果表明：黃土節(jié)理的抗剪強(qiáng)度關(guān)系符合摩爾-庫(kù)倫準(zhǔn)則,且粘聚力很小,可以忽略不計(jì);隨含水量的增加,黃土節(jié)理峰值內(nèi)摩擦角最初的變化幅度較小,當(dāng)大于某個(gè)含水量值時(shí),峰值內(nèi)摩擦角減小幅度變大,黃土節(jié)理強(qiáng)度隨含水量的變化規(guī)律可用指數(shù)形式進(jìn)行描述,并提出了節(jié)理剪切強(qiáng)度的經(jīng)驗(yàn)計(jì)算公式,驗(yàn)證了公式的合理性;黃土節(jié)理直剪試驗(yàn)存在尺寸效應(yīng),試樣尺寸主要影響節(jié)理面起伏度對(duì)剪切強(qiáng)度的貢獻(xiàn),尺寸越大,其剪切強(qiáng)度也越大;黃土節(jié)理剪切應(yīng)力-位移的關(guān)系曲線屬于無(wú)峰值的應(yīng)變硬化型曲線,并提出了合理的本構(gòu)模型;利用提出的本構(gòu)模型擬合試驗(yàn)結(jié)果,得到了節(jié)理初始剪切剛度,發(fā)現(xiàn)其隨含水量增加減小,隨正應(yīng)力增加呈線性增加。
[Abstract]:The shear strength characteristics of loess joints have an important effect on the stability of loess engineering with joints, and the shear strength characteristics of joints are closely related to the surface morphology of joints. Therefore, it is necessary to study the surface morphology of joints. Firstly, on the basis of a large number of field investigations, natural loess joint samples were collected in a suitable site, the joint surface morphology was measured by profilometer, and the contour curve of joint surface was drawn. The surface characteristic parameters of joints were calculated by statistical method, and then three parameters of high RMS root z1, peak density 畏, slope RMS root z2 were selected, and the single factor classification range was determined according to the statistical results and experience. The surface morphology of joints was evaluated by fuzzy mathematics method, and the synthetic characteristic parameters RJ and classification results of the surface morphology of natural loess joints were obtained. The effect of water content on the shear strength parameters of loess joints was studied by means of laboratory direct shear test, and the results of large-scale direct shear test and small direct shear test were compared. The influence of size effect on shear strength is studied. According to all the experimental results, the characteristics of shear stress-displacement curves of joints are studied. It is found that the joint surface morphology of natural loess soil samples is different between different sites, and the joint surface morphology is similar at the same site. The range of peak coefficient K of each joint plane is 2 ~ 3, the mean value is close to 3, indicating that the whole coordinate height distribution of joint surface is Gao Si distribution or quasi-Gao Si distribution, and it is found that RJ has a good linear correlation with joint shear strength. It shows that the method of joint surface classification is feasible. The results of direct shear test show that the shear strength relationship of loess joints accords with the Moor-Coulomb criterion, and the cohesion is very small, which can be ignored, and the initial variation of the peak internal friction angle of loess joints is small with the increase of water content. When the value of water content is greater than a certain value of water content, the amplitude of peak internal friction angle decreases and the variation of loess joint strength with water content can be described exponentially, and the empirical formula for calculating joint shear strength is put forward. The rationality of the formula is verified: the size effect exists in the direct shear test of loess joints, the size of the specimen mainly affects the contribution of the undulation of the joint surface to the shear strength, and the larger the size, the greater the shear strength; The relationship curve between shear stress and displacement of loess joints is a strain hardening curve without peak value, and a reasonable constitutive model is proposed, and the initial shear stiffness of joints is obtained by fitting the test results with the proposed constitutive model. It is found that it decreases with the increase of water content and increases linearly with the increase of normal stress.
【學(xué)位授予單位】：西安建筑科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TU444

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 胡偉;閔弘;陳健;徐開(kāi)民;;大型原位直剪試驗(yàn)設(shè)備改進(jìn)研制與應(yīng)用[J];巖土力學(xué);2015年03期

2 楊潔;榮冠;程龍;侯迪;王小江;;節(jié)理峰值抗剪強(qiáng)度試驗(yàn)研究[J];巖石力學(xué)與工程學(xué)報(bào);2015年05期

3 李同錄;王紅;付昱凱;梁燕;;黃土垂直節(jié)理形成機(jī)理的試驗(yàn)?zāi)M[J];地球科學(xué)與環(huán)境學(xué)報(bào);2014年02期

4 王鐵行;羅揚(yáng);王娟娟;;黃土節(jié)理抗剪強(qiáng)度特性試驗(yàn)研究[J];地下空間與工程學(xué)報(bào);2013年03期

5 王鐵行;王娟娟;房江鋒;;垂直節(jié)理影響的黃土隧道洞口段穩(wěn)定性分析[J];地下空間與工程學(xué)報(bào);2012年01期

6 王根龍;張茂省;蘇天明;曾慶銘;;黃土崩塌破壞模式及離散元數(shù)值模擬分析[J];工程地質(zhì)學(xué)報(bào);2011年04期

7 唐志成;夏才初;肖素光;;節(jié)理剪切應(yīng)力 位移本構(gòu)模型及剪脹現(xiàn)象分析[J];巖石力學(xué)與工程學(xué)報(bào);2011年05期

8 葉萬(wàn)軍;楊更社;常中華;顧華雄;;黃土邊坡剝落病害的發(fā)育特征及其發(fā)育程度評(píng)價(jià)[J];工程地質(zhì)學(xué)報(bào);2011年01期

9 駱進(jìn);項(xiàng)偉;吳云剛;王琰;;陜北黃土垂直節(jié)理形成機(jī)理的試驗(yàn)研究[J];長(zhǎng)江科學(xué)院院報(bào);2010年03期

10 冷希喬;陳禮偉;;大斷面黃土隧道變形特征及力學(xué)模型分析[J];四川建筑;2010年01期

相關(guān)會(huì)議論文 前2條

1 許宏發(fā);;節(jié)理表面分形特征與分維計(jì)算[A];面向21世紀(jì)的巖石力學(xué)與工程：中國(guó)巖石力學(xué)與工程學(xué)會(huì)第四次學(xué)術(shù)大會(huì)論文集[C];1996年

2 孫廣忠;;中國(guó)西北黃土中構(gòu)造節(jié)理及地質(zhì)工程意義[A];全國(guó)第三次工程地質(zhì)大會(huì)論文選集（上卷）[C];1988年

相關(guān)博士學(xué)位論文 前1條

1 葉朝良;黃土隧道施工地表裂縫形成機(jī)理及控制技術(shù)研究[D];西南交通大學(xué);2012年

相關(guān)碩士學(xué)位論文 前5條

1 樂(lè)崇浩;三軸減壓條件下裂隙性黃土的力學(xué)特性研究[D];長(zhǎng)安大學(xué);2012年

2 雷平;軟弱夾層對(duì)隧道圍巖及支護(hù)結(jié)構(gòu)的影響研究[D];長(zhǎng)安大學(xué);2008年

3 劉力;黃土強(qiáng)度特性及節(jié)理對(duì)黃土高邊坡穩(wěn)定的影響研究[D];天津大學(xué);2007年

4 丁增志;節(jié)理表面形貌研究及在非貫通節(jié)理巖體強(qiáng)度準(zhǔn)則中的應(yīng)用[D];同濟(jì)大學(xué);2007年

5 李濱;晉西黃土暗穴成因及其對(duì)公路危害研究[D];長(zhǎng)安大學(xué);2006年

，

本文編號(hào)：2025466