【摘要】：本文在綜合分析污染土的危害、污染土的宏觀特性研究、土體的微結(jié)構(gòu)特性研究以及污染土腐蝕機(jī)理研究的基礎(chǔ)上,明確了目前污染土研究中存在的問題,針對(duì)云南紅土,選取鹽酸和氫氧化鈉調(diào)節(jié)溶液的pH值,開展了pH值變化對(duì)云南紅土性質(zhì)影響的研究,主要包括紅土的擊實(shí)特性、直剪特性、壓縮特性、微結(jié)構(gòu)特性、影響機(jī)理,為有效防治水環(huán)境的安全以及基礎(chǔ)設(shè)施工程的安全提供理論依據(jù)。擊實(shí)紅土的宏微觀特性表明：浸潤(rùn)時(shí)間一定,隨pH值升高,紅土的最大干密度存在一個(gè)極大值和一個(gè)極小值,最優(yōu)含水率逐漸減小。pH值一定,隨養(yǎng)護(hù)時(shí)間延長(zhǎng),紅土的最大干密度存在兩個(gè)極大值和一個(gè)極小值,最優(yōu)含水率存在一個(gè)極大值和兩個(gè)極小值。隨pH值增大,從酸性到堿性的過程,擊實(shí)紅土的微結(jié)構(gòu)圖像呈現(xiàn)出密實(shí)性變差的特征,對(duì)應(yīng)的微結(jié)構(gòu)參數(shù)呈現(xiàn)出孔隙率增大、顆粒數(shù)減小、顆粒分布分維存在極大值、顆粒定向度減小的特征。剪切紅土的宏微觀特性表明：養(yǎng)護(hù)時(shí)間一定,隨pH值的升高,紅土的抗剪強(qiáng)度、黏聚力、內(nèi)摩擦角存在極大值。pH值一定,隨養(yǎng)護(hù)時(shí)間延長(zhǎng),紅土的抗剪強(qiáng)度、黏聚力、內(nèi)摩擦角逐漸減小。偏酸性或偏堿性條件下,剪前和剪后紅土微結(jié)構(gòu)圖像呈現(xiàn)出抗剪性變差特征,對(duì)應(yīng)微結(jié)構(gòu)參數(shù)孔隙率增大、顆粒數(shù)減小、顆粒分布分維和顆粒定向度減小。隨著養(yǎng)護(hù)時(shí)間的延長(zhǎng),紅土微結(jié)構(gòu)圖的孔隙增大、顆粒數(shù)減少、顆粒分布分維和顆粒定向度減小。壓縮紅土的宏微觀特性表明：養(yǎng)護(hù)時(shí)間一定,pH值較低的酸性條件,紅土不易被壓縮；pH值較高,堿性濃度較低時(shí),紅土不易壓縮,堿性濃度高時(shí),紅土易壓縮。pH值一定,隨養(yǎng)護(hù)時(shí)間延長(zhǎng),紅土逐漸變得易壓縮。隨pH值增大,從酸性到堿性的過程,壓縮前紅土的微結(jié)構(gòu)圖像呈現(xiàn)出微結(jié)構(gòu)參數(shù)孔隙率增大、顆粒數(shù)減小、顆粒分布分維和顆粒定向度減小,壓縮后紅土的微結(jié)構(gòu)圖像呈現(xiàn)出壓縮性增強(qiáng)特征,對(duì)應(yīng)的微結(jié)構(gòu)參數(shù)孔隙率增大、顆粒數(shù)減小、顆粒分布分維減小、顆粒定向度減小。隨養(yǎng)護(hù)時(shí)間延長(zhǎng),紅土微結(jié)構(gòu)圖的孔隙增大、顆粒數(shù)減少、顆粒分布分維和定向度減小。pH值變化對(duì)紅土的擊實(shí)特性、抗剪特性、壓縮特性的影響,可以從不同的pH值溶液與紅土之間的浸潤(rùn)作用、侵蝕作用、水解膠結(jié)作用、溶解作用來說明,對(duì)應(yīng)的微結(jié)構(gòu)特性和化學(xué)組成成分也隨之發(fā)生改變。
[Abstract]:On the basis of synthetically analyzing the harm of contaminated soil, the macroscopic characteristic of polluted soil, the microstructure of soil and the corrosion mechanism of contaminated soil, the problems existing in the study of contaminated soil are clarified in this paper, aiming at the red soil in Yunnan. The influence of the change of pH value on the properties of Yunnan laterite was studied by selecting the pH value of hydrochloric acid and sodium hydroxide adjusting solution, including compaction, direct shear, compression, microstructure and influence mechanism of laterite. It provides a theoretical basis for effectively preventing and controlling the safety of water environment and the safety of infrastructure engineering. The macroscopical and microscopic properties of compacted red soil indicate that the maximum dry density of red soil has a maximum value and a minimum value with the increase of pH value, and the optimum moisture content decreases gradually with the increase of curing time. There are two maximum values and one minimum value for the maximum dry density of the red soil and one maximum and two minimum values for the optimal moisture content. With the increase of pH value, the microstructural images of compacted laterite show the characteristics of poor compactness, the porosity increases, the number of particles decreases, and the fractal dimension of particle distribution is maximized. The characteristic of decreasing particle orientation. The macroscopical and microscopic properties of the shear laterite show that the shear strength, cohesion and internal friction angle of the red soil have a maximum value of pH value with the increase of pH value, and the shear strength and cohesion force of the red soil increase with the curing time. The angle of internal friction decreases gradually. Under the condition of partial acidity or alkalinity, the microstructural images of laterite before and after shearing showed a variation of shear resistance, the porosity of the corresponding microstructural parameters increased, the number of particles decreased, the distribution of particles and the orientation of particles decreased. With the prolongation of curing time, the pore size increases, the number of particles decreases, and the particle distribution and particle orientation decrease. The macroscopical and microscopic properties of compressed laterite show that the curing time is constant and the pH value is low, the pH value of red soil is not easy to be compressed, the red soil is not easy to compress when the alkaline concentration is low, and when the alkaline concentration is high, the red soil is easy to compress. With the increase of curing time, the red soil becomes more and more compressible. With the increase of pH value, the microstructural images of laterite before compression showed that the porosity of microstructural parameters increased, the number of particles decreased, the distribution of particles and the orientation of particles decreased during the process from acidity to alkalinity. The microstructural images of red soil show the characteristics of compressibility enhancement, the porosity of the corresponding microstructural parameters increases, the number of particles decreases, the fractal dimension of particle distribution decreases, and the orientation of particles decreases. With the increase of curing time, the pore size of red soil microstructural map increases, the number of particles decreases, and the particle distribution and orientation decrease. The effects of the change of particle distribution and orientation on the compaction, shear and compression properties of laterite are discussed. It can be explained from the infiltration, erosion, hydrolytic cementation and dissolution between different pH value solutions and laterite. The corresponding microstructure and chemical composition also change.
【學(xué)位授予單位】：昆明理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TU43;X53

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 仵彥卿;地下水與地質(zhì)災(zāi)害[J];地下空間;1999年04期

2 禹麗娥;;地下水生物除鐵效果及其動(dòng)力學(xué)研究[J];供水技術(shù);2009年03期

3 張信貴;易念平;吳恒;;不同pH水環(huán)境下土變形特性的試驗(yàn)研究[J];高校地質(zhì)學(xué)報(bào);2006年02期

4 易進(jìn)翔;楊康迪;;固化污泥填埋處置中的壓實(shí)特性研究[J];水利與建筑工程學(xué)報(bào);2013年01期

5 鮑碩超;王清;王蕊穎;許國(guó)輝;張舸;王子健;;廣西北海填方紅土的擊實(shí)特性及影響因素[J];吉林大學(xué)學(xué)報(bào)(地球科學(xué)版);2012年S3期

6 劉惟慶;吳偉;秦成崗;舒良鋒;;基于掃描電鏡的砂巖儲(chǔ)層分析:以白云凹陷珠江組三角洲前緣砂體為例[J];電子顯微學(xué)報(bào);2014年02期

7 甘德福;;采灌地下水作用下力學(xué)效應(yīng)與土體變形的探討[J];勘察技術(shù);1979年02期

8 茍曉琴，陳迪云;當(dāng)代環(huán)境中石造物的腐蝕破壞機(jī)理和保護(hù)[J];華東地質(zhì)學(xué)院學(xué)報(bào);1994年04期

9 馬琳;王清;原國(guó)紅;;pH對(duì)紅土性質(zhì)的影響[J];哈爾濱工業(yè)大學(xué)學(xué)報(bào);2009年10期

10 龐寶君;王立聞;何丹薇;楊震琦;;活性粉末混凝土高溫后的掃描電鏡試驗(yàn)研究[J];混凝土;2010年12期

相關(guān)碩士學(xué)位論文 前4條

1 王棟;堿性環(huán)境污染土的試驗(yàn)研究[D];太原理工大學(xué);2009年

2 伯桐震;酸污染紅土的宏微觀特性研究[D];昆明理工大學(xué);2012年

3 王盼;硫酸亞鐵侵蝕紅土的受力特性研究[D];昆明理工大學(xué);2013年

4 任禮強(qiáng);堿污染紅土的宏微觀特性研究[D];昆明理工大學(xué);2014年

，

本文編號(hào)：2249931