發(fā)布時間：2018-03-01 06:22

  本文關(guān)鍵詞： 土力學 酸雨作用 紅黏土 滲透性 壓實度 結(jié)構(gòu)損傷　出處：《巖石力學與工程學報》2016年S1期 　論文類型：期刊論文

【摘要】：酸雨會溶解紅黏土中的部分物質(zhì),是導(dǎo)致紅黏土路基病害的重要因素。研究紅黏土在酸雨環(huán)境下的滲透機制、提出紅黏土路基壓實度建議標準對于紅黏土地區(qū)路基設(shè)計具有很強的工程實際意義。設(shè)計新型的淋溶儀器,用不同p H值溶液模擬酸雨對原狀紅黏土進行淋溶后,進行滲透性試驗、物相分析試驗及電鏡微結(jié)構(gòu)掃描試驗,深入分析酸雨對桂林紅黏土滲透性的影響因素及影響機制;進一步通過試驗研究重塑紅黏土滲透系數(shù)與壓實度的變化關(guān)系。結(jié)果表明:紅黏土滲透系數(shù)隨干密度增大而減小;紅黏土中的主要物質(zhì)成分包括鐵、硅、鋁和鉀4種金屬元素的化合物均能被酸性物質(zhì)溶解,隨地下水遷移而流失,造成土體結(jié)構(gòu)孔隙比增大、內(nèi)部的孔隙連通性增強,酸雨的p H值越小,這些物質(zhì)的溶解程度越大,對紅黏土的滲透性影響越大;當在p H值≥3的酸雨地區(qū)用紅黏土作為路基填料時,控制路基壓實度≥95%可有效預(yù)防酸雨對紅黏土的不利作用。
[Abstract]:Acid rain dissolves some substances in red clay, which is an important factor leading to roadbed disease of red clay. The permeation mechanism of red clay in acid rain environment is studied. The paper puts forward that the recommended standard of compaction degree of red clay subgrade is of great practical significance for the design of roadbed in red clay area. A new type of leaching instrument is designed, which simulates the leaching of undisturbed red clay by acid rain with different pH values. The permeability test, phase analysis test and electron microscope microstructural scanning test were carried out to analyze the influence factors and mechanism of acid rain on the permeability of red clay in Guilin. The relationship between the permeability coefficient and compaction degree of remolded red clay is studied by experiment. The results show that the permeability coefficient of red clay decreases with the increase of dry density, and the main components of red clay include iron, silicon, silicon, iron and silicon. The compounds of aluminum and potassium can be dissolved by acidic substances, and lose with the migration of groundwater, resulting in the increase of structure / void ratio of soil mass and the increase of internal porosity connectivity. The smaller pH value of acid rain, the greater the dissolution degree of these substances. When red clay is used as subgrade filler in acid rain area with pH 鈮，

本文編號：1550788