Test Study on Effect of Free Iron Oxide in Granite Laterite on Cementation Characteristics of Laterite
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摘要: 花岗岩红土是华南地区广泛分布的一种区域性特殊土,游离氧化铁是影响其胶结特性的重要因素,研究游离氧化铁含量变化对土胶结强度的影响具有重要意义。以广州典型的花岗岩红土为研究对象,采用盐酸淋溶方法去除胶结物,对淋溶前后的土样分别进行直剪试验及含量分析,在此基础上探讨去胶结前后土强度的变化规律。研究表明:随着游离氧化铁含量的降低,土体的抗剪强度呈下降趋势,通过对胶结强度与游离氧化铁含量进行回归分析,其结果具有明显的二项式特征。胶结强度与含水量呈负相关性,与胶结物含量具有正相关性,以含水量和游离氧化铁含量为自变量,胶结强度为因变量,通过二元回归分析,建立的胶结强度算式,能较好地反映土胶结强度水平,具有一定应用价值。Abstract: Granite laterite is a regional special soil which is widely distributed in South China. The content of iron oxide is an important factor influencing the cementation characteristics of granite laterite. The study on the infulence of free iron oxide content on the cementation strength is of great significance. Taking classic granite laterite in Guangzhou as a research object, the hydrochloric acid osmotic method was used to remove iron oxide from typical granite laterite. Shear tests and content analysis of soil specimens before and after leaching were conducted. On the basis, the rule of soil strength before and after leaching was discussed. The results indicated that the shear peak strength of soil decreased with the decrease of the iron oxide content. By regression analysis of cementation strength and the free iron oxide content, the relation exhited obvious binomial characteristics. The cementation strength was negatively correlated with the water content, and had positive correlation with the cementation content. Taking the water content and free iron oxide content as independent variables and the cementation strength as dependent variable, the formula of cementation strength was established through binary regression analysis, which could better reflected the level of the comentation strength of the soil and had a certain application value.
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Key words:
- granite laterite /
- iron oxide /
- cementation strength /
- regression analysis
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[1] 汤连生,桑海涛,罗珍贵,等. 土体抗拉张力学特性研究进展[J]. 地球科学进展, 2015, 30(3): 297-309. [2] 王继庄. 游离氧化铁对红黏土工程特性的影响[J]. 岩土工程学报, 1983, 5(1): 147-156. [3] 汤连生,刘增贤,黄国怡,等. 红土中含铁离子物质的化学行为与力学效应[J]. 水文地质工程地质, 2004, 31(4): 45-49. [4] 张先伟,孔令伟. 氧化铁胶体与黏土矿物的交互作用及其对黏土土性影响[J]. 岩土工程学报, 2014, 36(1): 65-74. [5] ZHANG X W, KONG L W, CUI X L, et al. Occurrence characteristics of free iron oxides in soil microstructure: evidence from XRD, SEM and EDS[J]. Bulletin of Engineering Geology & the Environment, 2016, 75(4): 1493-1503. [6] ZHANG X W, KONG L W, YIN S, et al. Engineering geology of basaltic residual soil in Leiqiong, Southern China[J]. Engineering Geology, 2017, 220: 196-207. [7] 张庆华,孙银磊,汤连生,等. 南沙淤泥质土微观结构及力学特征的试验研究[J]. 工业建筑, 2021, 51(1): 110-117. [8] 周训华,廖义玲. 红黏土颗粒之间结构连结的胶体化学特征[J]. 贵州工业大学学报(自然科学版), 2004, 33(1): 26-29. [9] 李永豪,赵许川,刘静涛,等. Fe2O3和Al2O3胶结作用影响红黏土抗剪强度试验研究[J]. 路基工程, 2013(2): 19-21,25. [10] PENG X, YAN X, ZHOU H, et al. Assessing the contributions of sesquioxides and soil organic matter to aggregation in an Ultisol under long-term fertilization[J]. Soil & Tillage Research, 2015, 146: 89-98. [11] 傅鑫晖,颜荣涛,于海浩,等. 红黏土的强度机理[J]. 桂林理工大学学报, 2014, 34(4): 691-696. [12] 中国人民共和国水利部. 土工试验方法标准:GB/T 50123—2019 [S]. 北京:中国计划出版社, 2019. [13] 马琳,王清,原国红. pH对红土性质的影响[J]. 哈尔滨工业大学学报, 2009, 41(10): 255-258. [14] 张文博,柏巍,孔令伟,等. 淋溶时间对红黏土物理力学特性的影响[J]. 岩土力学, 2022, 43(2): 443-452. [15] ZHANG X W, LIU X Y, KONG L W, et al. Role of free iron oxides in the physicochemical and mechanical properties of natural clay[J/OL]. Engineering Geology, 2022[2022-03-20]. https://doi.org/10.1016/j.enggeo.2022.106665. [16] LIU X Y, ZHANG X W, KONG L W, et al. Shear strength anisotropy of natural granite residual soil[J/OL]. Journal of geotechnical and geoenvironmental engineering,2022 [2022-03-20]. https://doi.org/10.1061/(ASCE)GT.1943-5606.000 2709. [17] LIU X Y, ZHANG X W, KONG L W, et al. Disintegration of granite residual soils with varying degrees of weathering [J/OL]. Engineering Geology,2022 [2022-03-20]. https://doi.org/10.1016/j.enggeo.2022.106723. [18] LIU X Y, ZHANG X W, KONG L W, et al. Chemical weathering indices and how they relate to the mechanical parameters of granite regolith from southern China[J/OL]. Catena,2022 [2022-03-20]. https://doi.org/10.1016/j.catena.2022.106400. [19] 程昌炳,徐昌伟. 花岗岩残积土的胶结特性及其对力学性能的影响[J]. 岩土力学, 1986(2): 64-69. [20] 陈嘉林. 崩岗土体胶结物质与其抗剪强度的关系研究[D].福州: 福建农林大学, 2018. [21] 潘良福. 氧化铁胶体对崩岗土体抗剪特性的影响[D].福州: 福建农林大学, 2017. [22] 马琳,王清,原国红. 红土中游离氧化铁胶结作用的微观研究[J]. 河北工程大学学报(自然科学版), 2007, 24(1): 27-31. [23] 马琳,王清,原国红. 红土中游离氧化铁作用的试验研究[J]. 哈尔滨商业大学学报(自然科学版), 2007, 23(1): 53-57. [24] 程昌炳,陈琼,刘少军,等. 土中胶结强度的微观研究[J]. 华中农业大学学报, 1998, 17(2): 143-149. [25] 毕庆涛,姜国萍,丁树云. 含水量对红黏土抗剪强度的影响[J]. 地球与环境, 2005, 33(10): 144-147. [26] 王英辉,张全秀,田鹏程,等. 含水量变化对红黏土变形和强度特性的影响研究[J]. 工程勘察, 2009, 37(7): 10-13.
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