泥炭土腐殖酸环境室内模拟试验研究

Laboratory simulation of the humic group environment in peat soils

为能提供一种贴合天然环境的泥炭土腐殖酸环境,通过在冲洪积黏性土中掺入胡敏酸(Humic Acid, HA)试剂和富里酸(Fulvic Acid, FA)试剂人工制备泥炭土试样,并将试样浸泡在富里酸液中来模拟泥炭土腐殖酸环境。采用腐殖酸含量检测试验、扫描电镜(Scanning Electron Microscope, SEM)、X射线衍射(X-Ray Diffraction, XRD)、X射线荧光光谱(X-Ray Fluorescence spectroscopy, XRF)和无侧限抗压强度(qu)试验来评估模拟效果及可行性。结果表明,在pH值为6.0的浸泡液中浸泡90 d后,试样中富里酸实测质量分数超过了初始掺量,而胡敏酸的实测质量分数相较于初始掺量表现出波动性。试样中孔隙随着腐殖酸掺量的增加而逐渐发育连通,试样所含的原生矿物主要为石英和云母,主要元素为O、Si、Al和Fe。通过与天然泥炭土环境对比分析,揭示了模拟的腐殖酸环境在微观特征上与天然腐殖酸环境具有相似性。宏观力学试验结果表明,模拟试样的qu随腐殖酸掺量的增加而降低,对比分析显示模拟试样的力学性能与天然泥炭土的力学性能接近。以上结果表明,采用所提出的方法可以模拟出与天然泥炭土环境相近的泥炭土腐殖酸环境。

To provide an environment that closely resembles the natural humin acid environment of peat soil,this paper prepared artificial peat soil samples by incorporating Humic Acid(HA)reagent and Fulvic Acid(FA)reagents into floodplain clayey soil and immersing the samples in fulvic acid solution to simulate the peat soil humin group environment.The effectiveness and feasibility of this simulation were assessed through humin group content analysis,Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),X-Ray Fluorescence(XRF),and Unconfined Compressive Strength(UCS)tests.Results demonstrate that the samples closely resemble the appearance and morphology of natural peat soils when the humin group content reaches a combination of HA 9%and FA 3%.After a 90-day immersion in a pH 6.0 solution.The measured Fulvic Acid content in the samples surpassed the initial dosage.In contrast,the Humic Acid content displays variations compared to the initial levels.The pores in the samples were gradually developed and associated with the increase in the humin group,and the microstructure of the samples was an overhead structure with no fibers in the samples.Predominant minerals in the samples include quartz and mica,with the primary elements being oxygen,silicon,aluminum,and iron.A comparison of the simulated humin group environment with its natural counterpart reveals congruence in microscopic characteristics.The mechanical test results indicate that the strength of the simulated samples diminishes as the humin group content increases and the comparative assessment reveals that the mechanical attributes of the simulated samples are closely aligned with those of natural peat soil.Sensitivity analysis conducted by gene expression programming highlights Fulvic Acid content as the most influential factor on peat soil strength.The above results indicate that the methodology introduced in this study effectively replicates a humin group environment in peat soil,akin to its natural state.