黃土地區(qū)公路邊坡植物根系加筋特性研究
本文選題:黃土地區(qū) + 公路邊坡 ; 參考:《武漢理工大學(xué)》2014年碩士論文
【摘要】:隨著交通基礎(chǔ)設(shè)施建設(shè)的推進(jìn)和交通領(lǐng)域的各項(xiàng)深化改革,黃土地區(qū)的高等級(jí)公路建設(shè)得到了大規(guī)模發(fā)展,同時(shí)建設(shè)質(zhì)量在不斷的提高,建設(shè)水平在不斷的提升。黃土具有特殊的形成過(guò)程、成分和性質(zhì),在降雨條件下無(wú)防護(hù)邊坡容易沖刷破壞,而過(guò)去對(duì)邊坡抗沖刷穩(wěn)定性基本上都是從土力學(xué)的角度去計(jì)算分析,對(duì)降雨條件下因雨水降落對(duì)坡面的濺擊沖刷及雨水滲流對(duì)坡體基質(zhì)吸力的減少,從而導(dǎo)致邊坡穩(wěn)定性降低研究甚少。因此,對(duì)黃土地區(qū)公路邊坡植物根系加筋特性進(jìn)行深入系統(tǒng)地研究顯得十分必要,進(jìn)一步分析黃土的物理力學(xué)性質(zhì)、土質(zhì)特性對(duì)邊坡變形機(jī)理及變形規(guī)律的影響,不同植物根系對(duì)土體變形與強(qiáng)度特性的影響。探索適合黃土地區(qū)的植物配置及植物根系固土數(shù)學(xué)模型,為后續(xù)子午嶺林區(qū)公路生態(tài)建設(shè)順利推進(jìn)提供參考,具有重要的研究?jī)r(jià)值。 本論文以青島至蘭州國(guó)家高速公路雷家角(陜甘界)至西峰段生態(tài)邊坡技術(shù)研究實(shí)際工程為背景,該公路穿越子午嶺自然保護(hù)區(qū),子午嶺林區(qū)位于黃河中游,是黃土高原面積最大、植被最好的水源涵養(yǎng)林和綠色屏障,也是黃土高原最大的天然次生林區(qū)。邊坡生態(tài)防護(hù)是公路生態(tài)環(huán)境建設(shè)的重要內(nèi)容,對(duì)公路的建設(shè)和營(yíng)運(yùn)影響較大。本文針對(duì)黃土地區(qū)公路邊坡植物根系加筋特性展開(kāi)的主要研究?jī)?nèi)容如下: 首先,對(duì)黃土工程特性、植被根系加筋試驗(yàn)、植被作用下坡面水力侵蝕、植物根系的固土理論與模型的國(guó)內(nèi)外研究現(xiàn)狀進(jìn)行綜述。在此基礎(chǔ)上,敘述了雷西高速公路的邊坡特點(diǎn)、地形地貌及環(huán)境氣候條件,并利用X-射線衍射儀和電子掃描顯微鏡對(duì)子午嶺隧道進(jìn)口邊坡土體的礦物成分和微觀結(jié)構(gòu)進(jìn)行了研究。 其次,通過(guò)植物根系與土體的相互作用分析了植物根系對(duì)邊坡加固穩(wěn)定的機(jī)理。并實(shí)地選取雷西高速公路子午嶺隧道進(jìn)口處邊坡植被根系復(fù)合原狀土樣,,通過(guò)直剪試驗(yàn)和靜三軸固結(jié)排水試驗(yàn)研究了無(wú)根土、草根、灌木及喬木根系加筋土樣的應(yīng)力-應(yīng)變及強(qiáng)度特性,從得到的試驗(yàn)數(shù)據(jù)探討了在不同植物根系加筋作用下土樣抗剪強(qiáng)度指標(biāo)的變化規(guī)律。 最后,介紹了公路邊坡的沖刷機(jī)理,分析了植被莖葉及根系對(duì)邊坡抗沖刷的影響。接著從土體滲流作用力和臨界水力梯度對(duì)降雨條件下邊坡穩(wěn)定性破壞的機(jī)理進(jìn)行了詳細(xì)分析,概述了黃土這種非飽和土邊坡穩(wěn)定性的有限元分析理論,接著運(yùn)用GEO-SLOPE2007(SEEP/W、SLOPE/W及SIGMA/W耦合)軟件進(jìn)行降雨條件下的根-土復(fù)合體邊坡穩(wěn)定性分析,將降雨入滲作為土坡穩(wěn)定分析的重要因素,得出在降雨條件下,植物根系的加筋作用對(duì)坡體穩(wěn)定性有較大影響。 研究表明:黃土地區(qū)有著特殊的工程地質(zhì)特性,植物根系對(duì)加固、保護(hù)邊坡體有可支持的力學(xué)依據(jù),植物根系對(duì)內(nèi)摩擦角幾乎沒(méi)有影響,而對(duì)粘聚力有較大提高,能夠有效的穩(wěn)定邊坡。GEO-SLOPE有限元軟件通過(guò)滲流、邊坡及應(yīng)力-應(yīng)變?nèi)竽K耦合能很好的模擬降雨條件下植物根系對(duì)邊坡加筋后的應(yīng)力-應(yīng)變及穩(wěn)定性分析。
[Abstract]:With the promotion of the construction of traffic infrastructure and the deepening of the reform in the transportation field, the high grade highway construction in the loess area has been developed in a large scale. At the same time, the quality of the construction is constantly improving and the construction level is constantly improving. The loess has a special formation process, composition and nature, and the unprotected slope is easy to rush under the condition of rainfall. Brush failure, and in the past, the stability of the slope resistance to erosion is basically calculated from the angle of soil mechanics. In the condition of rainfall, the splash erosion and erosion of the slope surface and the decrease of the matrix suction of the slope are reduced, so that the slope stability is reduced very little. Therefore, the reinforcement of the root system of the slope in the loess area is reinforced. It is necessary to make a thorough and systematic study of the characteristics, and further analyze the physical and mechanical properties of the loess, the influence of the soil properties on the deformation mechanism and the deformation law of the slope, the influence of different plant roots to the deformation and strength characteristics of the soil, and explore the suitable mathematical model of the plant distribution and the root soil fixation in the loess region for the follow-up meridian. It is of great research value to provide reference for highway ecological construction in Ridge Forest Region.
This paper is based on the actual project of the ecological slope technology research of the Qingdao to Lanzhou national freeway (Shaanxi Gansu Province) to the Xifeng section. The highway traverses Ziwuling natural reserve and Ziwuling forest area is located in the middle reaches of the Yellow River. It is the largest water source conservation forest and green barrier in the Loess Plateau, and the largest in the Loess Plateau. Natural secondary forest area. Slope ecological protection is an important content of highway ecological environment construction, which has great influence on the construction and operation of highway. The main contents of this paper are as follows: the main research contents of the reinforcement characteristics of the root system of highway slope in the loess area are as follows:
First, the characteristics of the loess engineering, the reinforcement experiment of the vegetation root system, the hydraulic erosion of the slope surface under the action of vegetation, the theory of soil fixation of plant roots and the current research situation at home and abroad are reviewed. On this basis, the slope characteristics, topography and climate conditions of the Lei Xi expressway are described, and the X- ray diffractometer and electronic scanning display are used. The mineral composition and microstructure of the slope at the inlet of Ziwuling tunnel were studied by micromirror.
Secondly, through the interaction between plant root and soil soil, the mechanism of plant root system for slope stabilization is analyzed, and the complex original soil samples of the roots of slope vegetation at the inlet of Ziwuling tunnel of reisi expressway are selected in the field. The root soil, grass roots, shrubs and arbor roots are studied by direct shear test and static three axis consolidation and drainage test. The stress-strain and strength characteristics of samples are investigated. The shear strength indexes of soil samples reinforced by different root systems are discussed based on the obtained experimental data.
Finally, the mechanism of the scour of the highway slope is introduced, and the influence of the stem and leaf and root of the vegetation on the anti scour of the slope is analyzed. Then the mechanism of the slope stability damage under the soil seepage force and the critical hydraulic gradient is analyzed in detail, and the finite element analysis theory of the stability of the unsaturated soil slope is summarized. The GEO-SLOPE2007 (SEEP/W, SLOPE/W and SIGMA/W coupling) software was used to analyze the stability of the soil complex slope under rainfall, and the rainfall infiltration was taken as an important factor for the stability analysis of soil slope, and the effect of the reinforcement effect on the stability of the slope body was greatly influenced by the effect of the reinforcement effect on the plant roots.
The study shows that the loess area has special engineering geological characteristics. The root system has a supporting mechanical basis for strengthening and protecting the slope body. The root system has little influence on the internal friction angle, and the cohesive force is greatly improved. The effective stability of the slope.GEO-SLOPE is through seepage, slope and stress strain three major models. Block coupling can well simulate the stress strain and stability analysis of plant roots reinforced by slope under rainfall.
【學(xué)位授予單位】:武漢理工大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2014
【分類號(hào)】:U417.12
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 朱海之;;黃河中游馬蘭黃土顆粒及結(jié)構(gòu)的若干特征——油浸光片法觀察的結(jié)果[J];地質(zhì)科學(xué);1963年02期
2 李志剛,王春輝;公路邊坡沖刷機(jī)理初探[J];解放軍理工大學(xué)學(xué)報(bào)(自然科學(xué)版);2003年03期
3 李勇,朱顯謨,田積瑩;黃土高原植物根系提高土壤抗沖性的有效性[J];科學(xué)通報(bào);1991年12期
4 張金波;李婷;張媛;;甘肅省慶陽(yáng)市子午嶺林區(qū)保護(hù)與發(fā)展研究[J];林業(yè)建設(shè);2012年02期
5 鄒厚遠(yuǎn);程積民;張玉鈞;;陜北黃龍山植被保持水土的研究[J];水土保持通報(bào);1981年02期
6 程洪,張新全;草本植物根系網(wǎng)固土原理的力學(xué)試驗(yàn)探究[J];水土保持通報(bào);2002年05期
7 周正朝;上官周平;;子午嶺次生林植被演替過(guò)程的土壤抗沖性[J];生態(tài)學(xué)報(bào);2006年10期
8 羅斌,胡厚田,呂小平;南方花崗巖殘積層路塹邊坡坡面沖蝕研究[J];鐵道工程學(xué)報(bào);1999年03期
9 余新曉;;森林植被減弱降雨侵蝕能量的數(shù)理分析(續(xù))[J];水土保持學(xué)報(bào);1988年03期
10 李勇;徐曉琴;朱顯謨;田積瑩;;植物根系與土壤抗沖性[J];水土保持學(xué)報(bào);1993年03期
相關(guān)博士學(xué)位論文 前2條
1 楊璞;根土復(fù)合體極限載荷的數(shù)值計(jì)算方法和實(shí)驗(yàn)研究[D];清華大學(xué);2008年
2 宋朋燃;黃土邊坡沖刷破壞特征及數(shù)值模擬[D];吉林大學(xué);2013年
本文編號(hào):1873832
本文鏈接:http://www.sikaile.net/kejilunwen/jiaotonggongchenglunwen/1873832.html