A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
How Lead Affects the Hydraulic and Microscopic Properties of a Smectite
In a waste disposal site, the clay barrier is in contact with the lixiviates and it is necessary to study the long‐term evolution of the hydraulic and mechanical properties of the barrier in the presence of pollutants. This implies understanding the changes in its microscopic properties. The aim of this paper is to present a first approach of the study of the macroscopic and microscopic properties of a smectite in the presence of lead.
The material is a nearly pure Ca‐montmorillonite from Greece. The samples were initially compacted at Standard Proctor Optimum (SPO) and saturated with water or lead solutions at concentrations of 0.01 and 1M. The permeability was measured using the steady‐state method. The increase in the lead concentration is accompanied by an increase in the permeability of the sample: in presence of water, the permeability is equal to 2.3 10−12 ms−1; in the presence of lead, the permeability is equal to 3.3 10−12 ms−1 for the 0.01 M solution and reaches 4.1 10−12 ms−1 for the highest lead concentration. The X‐ray diffractograms show that the interlayer spacing is little influenced by the presence of lead, the interlayer distance varying from 1.9 nm for the sample hydrated with water to 1.8 nm for the sample hydrated with the lead solutions at the two concentrations. The results of the mercury intrusion tests are more sensitive to the lead presence, especially at the level of the inter‐aggregate pores (larger than 1.5 µm), whose diameter increases with the concentration in lead.
How Lead Affects the Hydraulic and Microscopic Properties of a Smectite
In a waste disposal site, the clay barrier is in contact with the lixiviates and it is necessary to study the long‐term evolution of the hydraulic and mechanical properties of the barrier in the presence of pollutants. This implies understanding the changes in its microscopic properties. The aim of this paper is to present a first approach of the study of the macroscopic and microscopic properties of a smectite in the presence of lead.
The material is a nearly pure Ca‐montmorillonite from Greece. The samples were initially compacted at Standard Proctor Optimum (SPO) and saturated with water or lead solutions at concentrations of 0.01 and 1M. The permeability was measured using the steady‐state method. The increase in the lead concentration is accompanied by an increase in the permeability of the sample: in presence of water, the permeability is equal to 2.3 10−12 ms−1; in the presence of lead, the permeability is equal to 3.3 10−12 ms−1 for the 0.01 M solution and reaches 4.1 10−12 ms−1 for the highest lead concentration. The X‐ray diffractograms show that the interlayer spacing is little influenced by the presence of lead, the interlayer distance varying from 1.9 nm for the sample hydrated with water to 1.8 nm for the sample hydrated with the lead solutions at the two concentrations. The results of the mercury intrusion tests are more sensitive to the lead presence, especially at the level of the inter‐aggregate pores (larger than 1.5 µm), whose diameter increases with the concentration in lead.
How Lead Affects the Hydraulic and Microscopic Properties of a Smectite
Shao, Jian‐Fu (editor) / Burlion, Nicolas (editor) / Souli, Hanène (author) / Fleureau, Jean‐Marie (author)
2013-02-19
7 pages
Article/Chapter (Book)
Electronic Resource
English
permeability , lead , clay , MIP , XRD
Hydraulic properties of smectite rich clay controlled by hydraulic gradients and filter types
| Online Contents | 2014
Smectite alteration and its influence on the barrier properties of smectite clay for a repository
| Online Contents | 2010
Mechanical properties of dense Ca-smectite clay
| Elsevier | 1989
Beyond smectite-based nanocomposites
| Online Contents | 2016
Preparation and properties of polypropylene reinforced by smectite
| British Library Online Contents | 1996