本文選題：土石混填體 + 正交試驗(yàn)設(shè)計(jì)��； 參考：《湖南大學(xué)》2015年碩士論文

【摘要】：隨著南方山區(qū)的基礎(chǔ)建設(shè)的快速發(fā)展,在路基工程建設(shè)中,越來越多的使用山體開挖而成的土石混填體作為路基填料。但是,由于填料的顆粒粒度變化很大且難以控制,加之含水率極不均勻,使得在實(shí)際工程中,土石混填體路基的質(zhì)量得不到保證,致使修筑的路基產(chǎn)生大量的沉陷或坍塌,從而導(dǎo)致路基結(jié)構(gòu)過早破壞,影響使用效率的發(fā)揮。加之南方山區(qū)雨水較多,土石混填路基長期處于濕潤狀態(tài),也對土石混填路基的性能產(chǎn)生很大的影響。本文針對存在的問題,為了深入了解土石混填體力學(xué)特性、變形特征及路用性能,對土石混填體進(jìn)行了一系列的研究,主要工作有：(1)在已有研究的基礎(chǔ)上,并全面考慮含水量、含石量、巖性、土性等因素的影響作用,采用YS30-3型應(yīng)力路徑三軸剪切試驗(yàn)機(jī),并基于正交試驗(yàn)方法進(jìn)行了一系列土石混填體大型三軸壓縮研究。試驗(yàn)結(jié)果表明：在三軸受力條件下,土石混填體在低圍壓下的應(yīng)變軟化特征不明顯,試樣的粘聚力c普遍較低而內(nèi)摩擦角j則比較高,且內(nèi)摩擦角φ更容易受其它因素的影響而發(fā)生顯著的變化；含石量對土石混填體的抗剪強(qiáng)度影響程度最大,隨試樣中的含石量從25%增加到70%,其內(nèi)摩擦角φ從34.54°近似線性增長至46.39°；含石量和圍壓分別是影響土石混填體體變特性最主要的內(nèi)因和外因,即在含水率、巖性、土性相同的情況下含石量越低試樣高壓剪縮性越明顯,含石量越高其低壓剪脹性越明顯。(2)采用FLAC 3D軟件,根據(jù)大型三軸試驗(yàn)的到試驗(yàn)參數(shù),建立了一個(gè)土石混填體高填路基的概化模型,對土石混填路基進(jìn)行了數(shù)值模擬分析,分析研究了各因素對土石混填路基穩(wěn)定性的影響,并對土石混填路基的施工提出了一些指導(dǎo)意見。(3)針對正常和灑水浸泡兩種情況,在特制的地槽中,制作了兩個(gè)土石混填路基模型,并對路基模型進(jìn)行分級加載,研究土石混填路基的受荷沉降變形特性。試驗(yàn)結(jié)果表明：對于正常情況,土石混填路基的結(jié)構(gòu)性較好,在到達(dá)極限荷載前,其p-s近似呈線性關(guān)系,到達(dá)極限荷載時(shí)路基邊坡突然出現(xiàn)大變形沉降,并發(fā)生破壞；而對于灑水浸泡情況,沉降變形發(fā)展緩慢,沒有明顯的拐點(diǎn),其極限荷載相對于正常情況也更小一些,含水量對土石混填路基的沉降變形,承載力都有比較顯著的影響；對土石混填路基土壓力的測量結(jié)果發(fā)現(xiàn),應(yīng)力在路基中的擴(kuò)散傳遞具有不對稱性,荷載的影響深度也有不對稱性。
[Abstract]:With the rapid development of the infrastructure construction in the southern mountainous area, more and more earth and rock mixed fillers are used as subgrade fillers in the subgrade engineering construction. However, because the particle size of fillers varies greatly and it is difficult to control, and the moisture content is very uneven, the quality of embankment can not be guaranteed in actual engineering, resulting in a large number of subgrade subsidence or collapse. Thus causes the subgrade structure to destroy prematurely, affects the use efficiency display. In addition, there is more Rain Water in the southern mountainous area, and the soil-rock embankment is in a wet state for a long time, which also has a great influence on the performance of the soil-rock embankment. Aiming at the existing problems, in order to understand the mechanical characteristics, deformation characteristics and road performance of earth and rock fill, a series of researches have been carried out in this paper, the main work of which is: 1) on the basis of existing research, and considering the water content in an all-round way. The influence of rock content, lithology and soil properties on large triaxial compression of a series of earth and rock mixed fillers was studied by using YS30-3 triaxial shear testing machine and orthogonal test method. The test results show that under the condition of triaxial loading, the strain softening characteristics of earth-rock mixed fill under low confining pressure are not obvious, the cohesive force c is generally lower and the internal friction angle j is higher. Moreover, the internal friction angle 蠁 is more easily influenced by other factors, and the content of stone has the greatest influence on the shear strength of the soil and rock mixture. With the increase of rock content from 25% to 70%, the angle of internal friction increases linearly from 34.54 擄to 46.39 擄. In the case of the same soil properties, the lower the rock content, the more obvious the shear shrinkage at high pressure, and the higher the rock content, the more obvious the dilatancy at low pressure.) the FLAC 3D software is used, and according to the parameters of the large triaxial test, In this paper, a general model of the embankment with soil and rock filling height is established, and the numerical simulation analysis of the subgrade is carried out, and the influence of various factors on the stability of the embankment is analyzed and studied. At the same time, some guiding opinions are put forward for the construction of earth-rock mixed filling subgrade. Aiming at the two situations of normal and sprinkling soaking, two soil-filled subgrade models are made in the specially made geosyncline, and the subgrade models are graded loaded. In this paper, the settlement and deformation characteristics of embankment filled with earth and rock are studied. The test results show that the structure of the embankment filled with earth and rock is better for normal condition. Before the ultimate load is reached, the p-s of the embankment is approximately linear. When the ultimate load is reached, large deformation and settlement of the embankment slope occur suddenly, and the failure occurs. For sprinkler immersion, the settlement deformation develops slowly, there is no obvious inflection point, and the ultimate load is smaller than the normal condition. The water content has a significant effect on the settlement deformation and bearing capacity of soil-rock embankment. It is found that the diffusion of stress in embankment is asymmetrical and the influence depth of load is asymmetric.
【學(xué)位授予單位】：湖南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：U416.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 曹文貴;張高才;王江營;張永杰;;不同水環(huán)境下土石混填路基穩(wěn)定性的模型試驗(yàn)研究[J];水文地質(zhì)工程地質(zhì);2014年04期

2 王江營;曹文貴;張超;汪輝平;;基于正交設(shè)計(jì)的復(fù)雜環(huán)境下土石混填體大型直剪試驗(yàn)研究[J];巖土工程學(xué)報(bào);2013年10期

3 周勇;劉升傳;;高填方路基填料的大型三軸試驗(yàn)研究[J];路基工程;2011年04期

4 鄒維列;李聰;汪建峰;鄧衛(wèi)東;王釗;;非飽和路堤對加載和降雨入滲響應(yīng)的模型試驗(yàn)研究[J];巖土工程學(xué)報(bào);2009年10期

5 姜景山;劉漢龍;程展林;丁紅順;左永振;;密度和圍壓對粗粒土力學(xué)性質(zhì)的影響[J];長江科學(xué)院院報(bào);2009年08期

6 徐文杰;胡瑞林;岳中琦;張瑞;王國良;;基于數(shù)字圖像分析及大型直剪試驗(yàn)的土石混合體塊石含量與抗剪強(qiáng)度關(guān)系研究[J];巖石力學(xué)與工程學(xué)報(bào);2008年05期

7 曹文貴;胡天浩;羅宏;趙明華;;土石混填路基壓實(shí)度檢測新方法探討[J];湖南大學(xué)學(xué)報(bào)(自然科學(xué)版);2008年02期

8 劉萌成;高玉峰;劉漢龍;;堆石料剪脹特性大型三軸試驗(yàn)研究[J];巖土工程學(xué)報(bào);2008年02期

9 劉萌成;高玉峰;劉漢龍;;應(yīng)力路徑條件下堆石料剪切特性大型三軸試驗(yàn)研究[J];巖石力學(xué)與工程學(xué)報(bào);2008年01期

10 李曉;廖秋林;赫建明;陳劍;;土石混合體力學(xué)特性的原位試驗(yàn)研究[J];巖石力學(xué)與工程學(xué)報(bào);2007年12期

相關(guān)博士學(xué)位論文 前4條

1 相彪;筑壩堆石料應(yīng)力路徑本構(gòu)關(guān)系研究[D];大連理工大學(xué);2009年

2 賈宇峰;考慮顆粒破碎的粗粒土本構(gòu)關(guān)系研究[D];大連理工大學(xué);2008年

3 陳曉斌;高速公路粗粒土路堤填料流變性質(zhì)研究[D];中南大學(xué);2007年

4 閻宗嶺;堆石體物理力學(xué)特性及其工程應(yīng)用研究[D];重慶大學(xué);2003年

相關(guān)碩士學(xué)位論文 前3條

1 梁彬;粗粒土復(fù)雜應(yīng)力路徑試驗(yàn)研究[D];河海大學(xué);2007年

2 董云;土石混合料力學(xué)特性的試驗(yàn)研究[D];重慶交通學(xué)院;2005年

3 高春玉;土石混合料路用性能的實(shí)驗(yàn)研究[D];四川大學(xué);2004年

，

本文編號：1992763