Evaluation of Constant Head Infiltration Test Analysis Methods for Field Estimation of Saturated Hydraulic Conductivity of Compacted Clay Liners

Author(s):  
D Cazaux
2021 ◽  
Vol 13 (13) ◽  
pp. 7301
Author(s):  
Marcin K. Widomski ◽  
Anna Musz-Pomorska ◽  
Wojciech Franus

This paper presents research considering hydraulic as well as swelling and shrinkage characteristics of potential recycled fine particle materials for compacted clay liner for sustainable landfills. Five locally available clay soils mixed with 10% (by mass) of NaP1 recycled zeolite were tested. The performed analysis was based on determined plasticity, cation exchange capacity, coefficient of saturated hydraulic conductivity after compaction, several shrinkage and swelling characteristics as well as, finally, saturated hydraulic conductivity after three cycles of drying and rewetting of tested specimens and the reference samples. The obtained results showed that addition of zeolite to clay soils allowed reduction in their saturated hydraulic conductivity to meet the required threshold (≤1 × 10−9 m/s) of sealing capabilities for compacted clay liner. On the other hand, an increase in plasticity, swelling, and in several cases in shrinkage, of the clay–zeolite mixture was observed. Finally, none of the tested mixtures was able to sustain its sealing capabilities after three cycles of drying and rewetting. Thus, the studied clayey soils mixed with sustainable recycled zeolite were assessed as promising materials for compacted liner construction. However, the liner should be operated carefully to avoid extensive dissication and cracking.


2000 ◽  
Vol 80 (4) ◽  
pp. 617-624 ◽  
Author(s):  
A. D. Startsev ◽  
D. H. McNabb

Soil compaction during forest harvesting generally reduces macropore space, which reduces infiltration and increases the potential for surface erosion and waterlogging. Hydrological effects of 3, 7 and 12 skidding cycles and their persistence were evaluated for 3 yr at 14 sites, which represented a range of soil texture and compaction conditions in the foothills and boreal forests of Alberta. Saturated hydraulic conductivity (HC) was determined using a constant head method on soil cores collected from 5- and 10-cm depths; unconfined infiltration rate of the surface soil (IR) was measured in situ with tension infiltrometers at near saturation. A significant (P < 0.05) increase in bulk density during skidding caused a significant reduction in both HC and IR after the first three cycles at eight sites where soil water potential at the time of skidding was higher than −15 kPa; the decrease at the other sites was not significant. Additional traffic, up to 12 cycles, did not cause a further significant decrease in HC or IR. The infiltration rate of soil compacted by three skidding cycles showed a recovery trend. However, in more intensively trafficked soils, compaction effects on infiltration remained significant for at least 3 yr, which was possibly attributed to heavy snowpacks preventing soil freezing at lower depths. Key words: Saturated hydraulic conductivity, unconfined infiltration rate, tension infiltrometers, skidders, boreal forest, Alberta


Soil Research ◽  
1997 ◽  
Vol 35 (4) ◽  
pp. 803 ◽  
Author(s):  
Neil McKenzie ◽  
David Jacquier

Prediction of the movement and storage of water in soil is central to quantitative land evaluation. However, spatial and temporal predictions have not been provided by most Australian soil surveys. The saturated hydraulic conductivity (Ks) is an essential parameter for description of water movement in soil and its estimation has been considered too difficult for logistic and technical reasons. The Ks cannot be measured everywhere and relationships with readily observed morphological variables have to be established. However, conventional morphology by itself is a poor predictor of Ks. We have developed a more functional set of morphological descriptors better suited to the prediction of Ks. The descriptors can be applied at several levels of detail. Measurements of functional morphology and Ks were made on 99 horizons from 36 sites across south-eastern Australia. Useful predictions of Ks were possible using field texture, grade of structure, areal porosity, bulk density, dispersion index, and horizon type. A simple visual estimate of areal porosity was satisfactory, although a more quantitative system of measurement provided only slightly better predictions. Regression trees gave more plausible predictive models than standard multiple regressions because they provided a realistic portrayal of the non-additive and conditional nature of the relationships between morphology and Ks. The results are encouraging and indicate that coarse-level prediction of Ks is possible in routine soil survey. Direct measurement of Ks does not appear to be generally feasible because of the high cost, dynamic nature of Ks, and substantial short-range variation in the field. Prediction is further constrained by the limited returns from more sophisticated morphological predictors. The degree to which this limits practical land evaluation is yet to be demonstrated.


1986 ◽  
Vol 66 (2) ◽  
pp. 249-259 ◽  
Author(s):  
G. D. BUCKLAND ◽  
D. B. HARKER ◽  
T. G. SOMMERFELDT

Saturated hydraulic conductivity (Ks) and drainable porosity (f) determined by different methods and for different depths were compared with those determined from the performance of drainage systems installed at two locations. These comparisons were made to determine which methods are suitable for use in subsurface drainage design. Auger hole and constant-head well permeameter Ks were 140 and 110%, respectively, of Ks determined from subsurface drains. Agreement of horizontal or vertical Ks, from in situ falling-head permeameters; to other methods was satisfactory providing sample numbers were large. Ks by Tempe cells was only 3–10% of drain Ks and in one instance was significantly lower than Ks determined by all other methods. At one site a profile-averaged value of f determined from the soil moisture characteristic curve (0–5 kPa) of semidisturbed cores agreed with that determined from drainage trials. At the other site, a satisfactory value of f was found only when the zone in which the water table fluctuated was considered. Results indicate that Ks determined by the auger hole and constant-head well permeameter methods, and f determined from the soil moisture characteristic curve of semidisturbed cores, are sufficiently reliable and practical for subsurface drainage design. Key words: Subsurface drainage, hydraulic conductivity, drainable porosity


Soil Research ◽  
1996 ◽  
Vol 34 (2) ◽  
pp. 213 ◽  
Author(s):  
TL Bird ◽  
TM Willis ◽  
GJ Melville

Field saturated hydraulic conductivity was measured in situ, at two depths in the B horizon, on irrigated soils in the Lower Macquarie Valley. Measurements were made with constant head well permeameters, using the single-head method, and water of moderate sodicity and high salinity. The hydraulic conductivity data were log-normally distributed for all soil groups and there were significant differences between some of these soil groups in mean hydraulic conductivity. Three soils exhibited significant differences in mean hydraulic conductivity between depths. Hydraulic conductivity measurements ranged up to 3 orders of magnitude within a soil. Variation in hydraulic conductivity estimates, both between and within soil groups, confirmed the variation observed in previous predictions of deep drainage, which were obtained using a semi-empirical model. A cluster analysis on hydraulic conductivity indicated that similar morphological soil properties did not necessarily reflect similar hydrologic properties. There was a strong relationship between hydraulic conductivity and exchangeable sodium percentage (ESP), hydraulic conductivity and clay content, and ESP and clay content. A model was developed to predict field saturated hydraulic conductivity from ESP and clay content data. Hydraulic conductivity measured in this study may not have been representative of percolation rates which would occur with low salinity irrigation water, but can be used to assess the risk of recharge from irrigation on different soils in the lower Macquarie Valley. Shallow watertables may potentially develop when the application of irrigation water greatly exceeds crop water requirements. Quantification of groundwater recharge will allow the likelihood of shallow watertable development in the Lower Macquarie Valley to be assessed.


MethodsX ◽  
2017 ◽  
Vol 4 ◽  
pp. 134-142 ◽  
Author(s):  
Jelmer J. Nijp ◽  
Klaas Metselaar ◽  
Juul Limpens ◽  
Harm P.A. Gooren ◽  
Sjoerd E.A.T.M. van der Zee

1992 ◽  
Vol 29 (3) ◽  
pp. 512-515 ◽  
Author(s):  
S. Leroueil ◽  
J. P. Le Bihan ◽  
R. Bouchard

Considering that (i) the hydraulic conductivity of compacted clays is smaller on the wet side of optimum; (ii) the plastic limit is the water content below which the soil develops fissures under small stresses; (iii) the plastic limit and the optimum standard Proctor water content are similar for many natural soils; and (iv) the strength of compacted clays, thus the limit of trafficability, is a function of (w – wopt)/Ip, relevant conditions for the design of clay liners and the evaluation of their hydraulic conductivity are proposed. Key words : compacted clay, liner, hydraulic conductivity, strength, design.


Sign in / Sign up

Export Citation Format

Share Document