Sürdürülebilir Kalkınma Amaçları

  • MakaleYayıncıda açık erişim2023Scopus SJRQ1
    Soil-dependent β and γ shape parameters of the Haverkamp infiltration model for 3D infiltration flow

    Yilmaz, D.; Lassabatere, L.; Moret-Fernandez, D.; Rahmati, M.; Angulo-Jaramillo, R.; Latorre, B.

    Estimating of soil sorptivity ((Figure presented.)) and saturated hydraulic conductivity ((Figure presented.)) parameters by field infiltration tests are widespread due to the ease of the experimental protocol and data treatment. The analytical equation proposed by Haverkamp et al. (1994) allows the modelling of the cumulative infiltration process, from which the hydraulic parameters can be estimated. This model depends on both initial and final values of the soil hydraulic conductivity, initial soil sorptivity, the volumetric water content increase ((Figure presented.)) and two infiltration constants, the so-called (Figure presented.) and (Figure presented.) parameters. However, to reduce the number of unknown variables when inverting experimental data, constant parameters such as (Figure presented.) and (Figure presented.) are usually prefixed to 0.6 and 0.75, respectively. In this study, the values of these constants are investigated using numerical infiltration curves for different soil types and initial soil water contents for the van Genuchten-Mualem (vGM) soil hydraulic model. Our new approach considers the long-time expansions of the Haverkamp model, the exact soil properties such as (Figure presented.), (Figure presented.) and initial soil moisture to derive the value of the (Figure presented.) and (Figure presented.) parameters for each specific case. We then generated numerically cumulative infiltration curves using Hydrus-3D software and fitted the long-time expansions to derive the value of the (Figure presented.) and (Figure presented.) parameters. The results show that these parameters are influenced by the initial soil water content and the soil type. However, for initially dry soil conditions, some prefixed values can be proposed instead of the currently used values. If an accurate estimate of (Figure presented.) and (Figure presented.) is the case, then for coarse-textured soils such as sand and loamy sand, we propose the use of 0.9 for both constants. For the remaining soils, the value of 0.75 can be retained for (Figure presented.). For (Figure presented.) constant, 0.75 and 1.5 values can be considered for, intermediate permeable soils (sandy loam and loam) and low permeable soils (silty loam and silt), respectively. We clarify that the results are based on using the vGM model to describe the hydraulic functions of the soil and that the results may differ, and the assumptions may change for other models.

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  • MakaleYalnız künye2022Scopus SJRQ1
    Testing Simplified Beerkan Infiltration (SBI) Methods on Technosol to Estimate the Saturated Hydraulic Conductivity

    Yilmaz, D.

    The development of infiltration techniques has facilitated the estimation of soils hydraulic properties. Among these, the simplified Beerkan infiltration methods are the most attractive because of their ease of use and low cost. However, they have not been tested on a wide range of soils, more particularly on technosols which are more and more present in urban areas. The transient method using the preliminary part of the infiltration curve and the long-time method using the part of the curve where the infiltration flow becomes permanent were tested on 32 infiltrations collected on 5 experimental technosols to estimate the saturated hydraulic conductivity Ks. The results show that the estimated Ks for both methods are in the same order of magnitude when compared to the reference value. The steady state approach has led to better results of Ks estimates related with R2 factor of 0.902 versus 0.798 for transient one. However, in the case of Basic Oxygen Furnace slag technosol the differences in Ks estimates are more pronounced and additional investigations are necessary. If no complex reaction inside the microstructure occurs, then the simplified method may be used for a rough estimate of Ks on technosols.

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  • MakaleYalnız künye2021Scopus SJRQ2
    Alternative α* Parameter Estimation for Simplified Beerkan Infiltration Method to Assess Soil Saturated Hydraulic Conductivity

    Yilmaz, D.

    Abstract: In situ characterization of the saturated hydraulic conductivity (Ks) requires a large number of experiments, sampling, and laboratory measurements that are time-consuming and expensive. Simplified Beerkan Infiltration (SBI) method was developed to estimate an approximate Ks based on the infiltration curve without any sampling procedures. For that purpose, α* parameter, which is used in the calculation of Ks, was commonly set to a fixed value based on soil texture. This approach was not sufficient for an accurate Ks estimation. For a relatively dry soil, a new approach involving an empirical structural parameter was proposed to calculate an approximation of the α* parameter based on the shape of the steady state asymptote of the Beerkan cumulative infiltration. The new α* parameter was tested on simplified Beerkan infiltration (SBI) method in over 32 Beerkan experiments selected from the Soil World Infiltration Global (SWIG) database. The steady state SBI (SSBI) method estimated Ks with an accuracy close to those estimated with the BEST (Beerkan Estimation Soil Transfer) method. The R2 correlation factor for the SSBI method in Ks estimation with BEST intercept and steady methods were 0.982 and 0.994, respectively. For the transient SBI method, the R2 correlation factors calculated with BEST methods were lower; 0.858 and 0.827, respectively. Therefore, the application of the new α* parameter to the steady state simplified Beerkan approach allows an easy, inexpensive way to estimate accurately Ks.

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  • MakaleAçık Erişim2021Scopus SJRQ1
    Sequential infiltration analysis of infiltration curves measured with disc infiltrometer in layered soils

    Moret-Fernández, D.; Latorre, B.; Lassabatere, L.; Di Prima, S.; Castellini, M.; Yilmaz, D.; Angulo-Jaramilo, R.

    The soil sorptivity, S, and saturated hydraulic conductivity, Ks, can be estimated from the inverse analysis of a cumulative infiltration curve using the quasi-exact implicit (QEI) formulation or its corresponding 4-Terms (4T) approximation. Although these models consider the soil as homogeneous media, there is no information about how heterogeneous profiles can affect the inferred soil properties. This work analyzes the influence of layered soils on Ks and S estimates using QEI and 4T models, and designs a new procedure for treating infiltration curves measured on layered soil profiles. The Sequential Infiltration Analysis (SIA) method considers a sequence of increasing time series from the cumulative infiltration data to estimate Ks and S, and its corresponding RMSE as a function of the number of samples used. A procedure to estimate the thickness of the upper uniform soil layer from the estimated wetting front advance (WFA) is also reported. The SIA method was applied on: (i) synthetic homogeneous profiles of loam soil and six layered profiles involving a 1, 2 and 3 cm thickness loam layer over silty or sandy loam soils, respectively, (ii) stratified laboratory soil columns, and (iii) 20 experimental infiltrations performed in a semiarid region of North-Eastern Spain. Similar results were found between QEI and 4T models for all cases. Erroneous estimates of Ks and S were observed when the total infiltration time series was considered for the analysis, regardless of the presence of soil layering. In opposite, estimates improved when the SIA method was applied to the layered systems. The SIA method exploits the fact that the RMSE increases when the wetting front reaches the interface between the soil layers. Such increase allows: (i) detection of the soil heterogeneity, (ii) determination of the infiltration time, to, required for the wetting front to reach the lower layer, and, (iii) accurate estimates of the upper layer Ks and S along with its thickness. Laboratory experiments on layered soils and field measurements demonstrated that the SIA method could be satisfactorily applied on different curves with contrasting shapes and magnitudes. Although soil layering encountered on most field samplings restricted the treatment of the observed infiltrations to short-medium times, the SIA method allowed robust estimates of Ks and S. These results indicate that the proposed method is a promising tool for characterizing the hydraulic properties of layered and heterogeneous soil profiles.

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  • MakaleYalnız künye2016Scopus SJRQ2
    Storm water retention and actual evapotranspiration performances of experimental green roofs in French oceanic climate

    Yilmaz, D.; Sabre, M.; Lassabatère, L.; Dal, M.; Rodriguez, F.

    Green roofs are promising urban management tools from the standpoint of both rainwater management and microclimatology. They are considered as a storm water mitigation technique and may also favour evapotranspiration fluxes, which can be beneficial for urban comfort during summer periods. In France, however, water retention performance of green roofs remains unknown, and published values are often unsuitable. Six experimental roofs, including two thicknesses of growing media, three types of vegetation cover and bare surfaces, were monitored for two years in Nantes and compared to an experimental gravel flat roof. The thickest media combined with the most densely vegetated cover yields the best results in terms of storm water mitigation and actual evapotranspiration. In winter, the rainwater retention performance is clearly dependent on the type of experimental roof vegetation. This kind of experimental set-up is well suited to assisting urban planners design tools for storm water mitigation in buildings.

    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    • SDG 13 · İklim Eylemi
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