酸碱侵蚀下红土的工程特性与受损化学成分的关系研究
发布时间：2019-04-12 15:46
【摘要】：环境污染增大了云南地区库水中氯离子的含量,从而形成大量的HC1对筑坝红土造成侵蚀；而用于土石坝防渗加固的传统材料中水泥与石灰被广泛采用,其水化后产生大量的Ca(OH)2亦长期缓慢侵蚀着弱酸性的筑坝红土。鉴于上述情况,本文分别开展了HC1和Ca(OH)2侵蚀筑坝红土的化学加速寿命试验、受蚀红土的室内土工试验及其受损化学成分的离子浓度检测试验。通过对试验数据的整理与分析,明确了HC1和Ca(OH)2侵蚀对筑坝红土的工程特性及化学成分所引起的变化；并从化学反应和细观演变角度着手,定性地阐明了受蚀筑坝红土工程特性与化学成分的变化机理以及二者之间存在的紧密联系；据此采用多元逐步回归分析方法,分别建立了HC1和Ca(OH)2侵蚀筑坝红土的各主要工程特性指标与受损化学成分的量化关系模型。 结果表明：(1)HC1消耗了筑坝红土中起到包裹、胶结作用的化学成分Fe203和Al2O3,致使酸蚀筑坝红土的工程特性发生变化,主要表现为渗透系数K、内摩擦角φ压缩系数αv,、液性指数IL以及粉粒含量Ps增大,而凝聚力c、比重Gs、塑性指数IP以及粘粒含量PC则减小；(2)Ca(OH)2消耗了筑坝红土中起到胶结、填充作用的化学成分Si02.Ti02和Al2O3,从而引起碱蚀筑坝红土工程特性的改变,主要体现为渗透系数K、压缩系数αv、液性指数IL以及粉粒含量Ps均增大,而凝聚力c、内摩擦角φ、比重Gs、塑性指数IP以及粘粒含量PC都减小；(3)酸蚀筑坝红土各主要工程指标的回归方程中,除了c、φ、Gs的校正决定系数略偏低(R2adj=0.541～0.692),其他指标K、av、Ip、IL、Ps、Pc的校正决定系数均在0.700以上(R2adi=0.729～0.937)；(4)对于碱蚀筑坝红土各主要工程指标的回归方程,除了φ、αv的校正决定系数略偏低(R2adj=0.555～0.657),其他指标K、c、Gs、Ip、IL、Ps、Pc的校正决定系数也都在0.700以上(R2adj=0.707-0.898)；(5)筑坝红土的受损化学成分含量对大部分工程指标的变化的解释程度都在70%以上,可见在酸碱侵蚀筑坝红土中,主要工程指标的变化与化学成分的受损存在着显著的量化关系,据此可以为红土室内土工试验的结果评价和数据取舍提供参考,又可以为深入研究关于评估土石坝病害程度和预测土石坝使用寿命的方法提供一个新思路。
[Abstract]:Environmental pollution increased the content of chloride ions in reservoir water in Yunnan, resulting in the formation of a large number of HC1 to dam-building laterite erosion; In addition, cement and lime are widely used in the traditional materials used for seepage prevention and reinforcement of earth-rock dams. After hydration, a large amount of Ca (OH)-2 also slowly erodes the weakly acidic red earth of dam-building. In view of the above situation, the chemical accelerated life test of HC1 and Ca (OH) 2 eroded laterite, the indoor geotechnical test of corroded red soil and the ion concentration test of damaged chemical composition were carried out in this paper. Through the analysis of the test data, the change of the engineering characteristics and chemical composition caused by the erosion of HC1 and Ca (OH) 2 on the dam-building red soil was clarified. From the point of view of chemical reaction and meso-evolution, the change mechanism of engineering characteristics and chemical composition of corroded red earth and the close relationship between them are expounded qualitatively. Based on the method of multiple stepwise regression analysis, the quantitative relation models between the main engineering characteristics and the damaged chemical composition of HC1 and Ca (OH) 2 eroded red soil are established respectively. The results show that: (1) HC1 consumes the envelopes in dam-building red soil, and the chemical composition of cementation, Fe203 and Al2O3, results in the change of engineering characteristics of acid-etched laterite. The main results are as follows: permeability coefficient K, internal friction angle 蠁 compression coefficient 伪 _ v, internal friction angle 蠁 compression coefficient 伪 _ v, etc. Liquid index (IL) and powder content (Ps) increased, but cohesion c, specific Gs, plasticity index (IP) and clay content (PC) decreased. (2) Ca (OH) 2 consumes the cementitious and filling chemical composition Si02.Ti02 and Al2O3, which lead to the change of the engineering characteristics of alkaline erosion laterite, which is mainly reflected in the permeability coefficient K, compression coefficient 伪 v, and so on. Liquid index IL and powder content Ps increased, while cohesion c, internal friction angle 蠁, specific Gs, plasticity index IP and clay content PC decreased. (3) in the regression equation of the main engineering indexes of red soil, except for c, 蠁, Gs, the correction determining coefficient (R2adj=0.541~0.692) is slightly lower, the other indexes K, v, I p, IL, PS, K, V, I p, IL, PS, etc. The correction decision coefficients of Pc were above 0.700 (R2adi=0.729~0.937). (4) for the regression equation of the main engineering indexes of red soil, except 蠁 and 伪 v, the correction determining coefficient (R2adj=0.555~0.657) is slightly lower, the other indexes K, c, GS, Ip, IL, PS, and so on. The correction decision coefficients of Pc were also above 0.700 (R2adj=0.707-0.898); (5) the degree of interpretation of the content of damaged chemical composition of dam-building red soil to most engineering indexes is more than 70%, so it can be seen in acid-alkali erosion of red soil for dam-building. There is a significant quantitative relationship between the change of main engineering indexes and the damage of chemical composition, which can be used as a reference for the evaluation of the results and the selection of data of the geotechnical test in the laboratory of lateritic soil. It can also provide a new idea for the in-depth study on the assessment of the degree of earth-rock dam disease and the prediction of the service life of the earth-rock dam.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV221.2;P642.132
本文编号：2457145
[Abstract]:Environmental pollution increased the content of chloride ions in reservoir water in Yunnan, resulting in the formation of a large number of HC1 to dam-building laterite erosion; In addition, cement and lime are widely used in the traditional materials used for seepage prevention and reinforcement of earth-rock dams. After hydration, a large amount of Ca (OH)-2 also slowly erodes the weakly acidic red earth of dam-building. In view of the above situation, the chemical accelerated life test of HC1 and Ca (OH) 2 eroded laterite, the indoor geotechnical test of corroded red soil and the ion concentration test of damaged chemical composition were carried out in this paper. Through the analysis of the test data, the change of the engineering characteristics and chemical composition caused by the erosion of HC1 and Ca (OH) 2 on the dam-building red soil was clarified. From the point of view of chemical reaction and meso-evolution, the change mechanism of engineering characteristics and chemical composition of corroded red earth and the close relationship between them are expounded qualitatively. Based on the method of multiple stepwise regression analysis, the quantitative relation models between the main engineering characteristics and the damaged chemical composition of HC1 and Ca (OH) 2 eroded red soil are established respectively. The results show that: (1) HC1 consumes the envelopes in dam-building red soil, and the chemical composition of cementation, Fe203 and Al2O3, results in the change of engineering characteristics of acid-etched laterite. The main results are as follows: permeability coefficient K, internal friction angle 蠁 compression coefficient 伪 _ v, internal friction angle 蠁 compression coefficient 伪 _ v, etc. Liquid index (IL) and powder content (Ps) increased, but cohesion c, specific Gs, plasticity index (IP) and clay content (PC) decreased. (2) Ca (OH) 2 consumes the cementitious and filling chemical composition Si02.Ti02 and Al2O3, which lead to the change of the engineering characteristics of alkaline erosion laterite, which is mainly reflected in the permeability coefficient K, compression coefficient 伪 v, and so on. Liquid index IL and powder content Ps increased, while cohesion c, internal friction angle 蠁, specific Gs, plasticity index IP and clay content PC decreased. (3) in the regression equation of the main engineering indexes of red soil, except for c, 蠁, Gs, the correction determining coefficient (R2adj=0.541~0.692) is slightly lower, the other indexes K, v, I p, IL, PS, K, V, I p, IL, PS, etc. The correction decision coefficients of Pc were above 0.700 (R2adi=0.729~0.937). (4) for the regression equation of the main engineering indexes of red soil, except 蠁 and 伪 v, the correction determining coefficient (R2adj=0.555~0.657) is slightly lower, the other indexes K, c, GS, Ip, IL, PS, and so on. The correction decision coefficients of Pc were also above 0.700 (R2adj=0.707-0.898); (5) the degree of interpretation of the content of damaged chemical composition of dam-building red soil to most engineering indexes is more than 70%, so it can be seen in acid-alkali erosion of red soil for dam-building. There is a significant quantitative relationship between the change of main engineering indexes and the damage of chemical composition, which can be used as a reference for the evaluation of the results and the selection of data of the geotechnical test in the laboratory of lateritic soil. It can also provide a new idea for the in-depth study on the assessment of the degree of earth-rock dam disease and the prediction of the service life of the earth-rock dam.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV221.2;P642.132
【参考文献】
相关期刊论文 前10条
1 刘振波,赵春宏;云南红粘土工程特性及岩土工程问题与对策[J];电力勘测设计;2005年03期
2 姚慧丽;王英辉;祁士华;游远航;;土壤-水环境系统有机氯农药地球化学特征[J];环境科学与技术;2008年06期
3 巴恒静;张武满;;混凝土寿命加速实验方法与预测[J];硅酸盐学报;2007年02期
4 李涛;胡金生;肖红;任秀文;;乙酸和碳酸对粘土土工性状影响的试验[J];煤田地质与勘探;2008年06期
5 杨华舒;杨宇璐;闫毅志;王毅;汪皓;胡应庭;;碱性固化材料对红土地基的化学侵蚀[J];建筑材料学报;2013年01期
6 平田健正;郑毅;;有机氯化物对地下水的污染[J];世界地质;1990年01期
7 符必昌,黄英,方丽萍;红土化作用及红土的工程地质分类[J];云南地质;1997年02期
8 孙重初;酸液对红粘土物理力学性质的影响[J];岩土工程学报;1989年04期
9 Chirdchanin MODMOLTIN,陆江,Katsutada ONITSUKA;腐殖酸与盐分浓度对石灰加固土有明黏土的影响以及微观结构研究[J];岩土工程学报;2004年02期
10 朱春鹏;刘汉龙;张晓璐;;酸碱污染土压缩特性的室内试验研究[J];岩土工程学报;2008年10期
，本文编号：2457145
本文链接：https://www.wllwen.com/kejilunwen/shuiwenshuili/2457145.html
