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SUSTAINABILITY of COMPACTED CLAY LINERS and SELECTED PROPERTIES of CLAYS MONOGRAFIE KOMITETU INŻYNIERII ŚRODOWISKA POLSKA AKADEMIA NAUK Vol

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SUSTAINABILITY of COMPACTED CLAY LINERS and SELECTED PROPERTIES of CLAYS MONOGRAFIE KOMITETU INŻYNIERII ŚRODOWISKA POLSKA AKADEMIA NAUK Vol SUSTAINABILITY OF COMPACTED CLAY LINERS AND SELECTED PROPERTIES OF CLAYS CLAYS OF PROPERTIES LINERS AND SELECTED CLAY COMPACTED OF SUSTAINABILITY MONOGRAFIE KOMITETU INŻYNIERII ŚRODOWISKA POLSKA AKADEMIA NAUK vol. 127 SUSTAINABILITY OF COMPACTED CLAY LINERS AND SELECTED PROPERTIES OF CLAYS Marcin K. Widomski ISBN 978-83-63714-26-0 LUBLIN 2016 POLSKA AKADEMIA NAUK KOMITED INŻYNIERII ŚRODOWISKA MONOGRAFIE vol. 127 SUSTAINABILITY OF COMPACTED CLAY LINERS AND SELECTED PROPERTIES OF CLAYS Marcin K. Widomski Lublin 2016 Reviewers: Prof. dr hab. inż. Tomasz Winnicki Prof. dr hab. Witold Stępniewski Editorial Board: prof. Anna Anielak prof. Marian Mazur prof. Kazimierz Banasik prof. Korneliusz Miksch prof. January Bień dr hab. inż. Maciej Mrowiec prof. Ryszard Błażejewski prof. Hanna Obarska–Pempkowiak prof. Michał Bodzek dr hab. Artur Pawłowski dr hab. inż. Marcin Chodak prof. Lucjan Pawłowski prof. Wojciech Dąbrowski prof. Tadeusz Piecuch prof. Marzenna Dudzińska dr hab. inż. Bernard Quant dr hab. inż. Katarzyna Ignatowicz prof. Czesława Rosik–Dulewska prof. Janusz Jeżowiecki prof. Zofia Sadecka dr hab. inż. Katarzyna Juda–Rezler prof. Marek Sozański dr hab. inż. Małgorzata Kabsch– prof. Joanna Surmacz-Górska Korbutowicz, prof. Kazimierz Szymański dr hab. inż. Piotr Koszelnik prof. Józefa Wiater prof. Mirosław Krzemieniewski prof. Tomasz Winnicki dr hab. inż. Izabela Majchrzak–Kucęba prof. Mirosław Żukowski ©Komitet Inzynierii Srodowiska PAN Monografie Komitetu Inżynierii Środowiska PAN vol. 127 ISBN 978-83-63714-26-0 2 Content List of symbols ............................................................................................................ 5 1. Preface ..................................................................................................................... 7 2. Literature review ................................................................................................... 11 2.1. Landfilling as a part of sustainable waste management system ..................... 11 2.2. Sustainable landfilling .................................................................................... 17 2.3. Material selection recommendation ............................................................... 27 2.4. Determinants of liner sustainability ................................................................ 30 2.4.1. Hydraulic conductivity of compacted clays ............................................ 30 2.4.2. Swell-shrink properties ............................................................................ 33 2.4.3. Cyclic drying and wetting ....................................................................... 36 2.5. Summary of literature review ......................................................................... 40 3. Aim and scope of dissertation ............................................................................... 43 4. Materials and methods ........................................................................................... 44 4.1. Field and laboratory measurements ................................................................ 45 4.1.1. General and geotechnical characteristics ................................................. 45 4.1.2. Proctor tests and hydraulic conductivity measurements .......................... 46 4.1.3. Swell and shrink characteristics of compacted clays ............................... 49 4.1.4. Hydraulic conductivity after drying and wetting cycles .......................... 51 4.1.5. Water retention characteristics ................................................................ 52 4.2. Materials and methods applied to numerical modeling .................................. 53 4.2.1. Input data ................................................................................................. 53 4.2.2. Initial and boundary conditions ............................................................... 56 4.2.3. Model calibration and sensitivity analysis............................................... 58 4.2.4. Bottom liner seepage ............................................................................... 59 5. Results and discussion ........................................................................................... 60 5.1. Results of field and laboratory studies ........................................................... 60 5.1.1. General characteristics ............................................................................. 60 5.1.2. Strength parameters ................................................................................. 65 3 5.1.3. Atterberg limits and plasticity chart ........................................................ 65 5.1.4. Hydraulic conductivity under natural conditions .................................... 68 5.1.5. Water retention curves of tested materials under natural conditions ....... 69 5.1.6. Characteristics of tested materials after compaction ............................... 71 5.1.7. Shrinkage characteristics of compacted clay materials ........................... 80 5.1.8. Water retention curves of compacted materials ...................................... 84 5.1.9. Saturated hydraulic conductivity of compacted clays after drying and rewetting ............................................................................................................ 91 5.1.10. Correlations between selected characteristics of tested substrates ........ 95 5.1.11. Verification of applicability according to ITB national criteria .......... 100 5.2. Results of numerical modeling ..................................................................... 102 5.2.1. Hydraulic efficiency of liner compacted at wopt<wf<1.2wopt .................. 102 5.2.2. Hydraulic efficiency of clay liner compacted at wf<wopt ....................... 114 5.3. Proposal of material selection criteria for sustainable CCL ......................... 129 6. Summary ............................................................................................................. 132 7. Conclusions ......................................................................................................... 141 8. Bibliography ........................................................................................................ 144 4 List of symbols α – water retention curve fitting parameter, cm-1; t – time duration required for lowering water level from h1 to h2, s; 3 -3 r – residual volumetric water content, assumed r,=0, m m ; 3 -3 s – saturated volumetric water content, m m ; µ – dynamic viscosity of water, kg m-1 s-1; -3 ρs – density of soil, kg m ; -3 ρw – density of water, kg m ; – dimensionless tortuosity factor; ø – dimensionless porosity; ψ – soil water potential, cm; a – water standpipe cross section area, m2; ar – dimensionless anisotropy ratio, assumed constant for saturated and unsaturated conditions; – water retention curve fitting parameter, m-1; 2 As – soil sample cross section area, m ; clay – clay fraction content, %; COLE – dimensionless coefficient of linear extensibility; – pressure head gradient; e – void ratio; -1 EVa – actual daily evapotranspiration mm, day ; g – gravity vector, m s-2; h – water pore pressure head, m; h1, h2 – water level heights, m; hi – initial height of substrate specimen, after molding, before saturation, m; hs – height of swelled sample, m; hs – soil suction pressure, cm H2O; hw – difference of water table height between reservoir of the permeameter and cylinder containing soil sample, m; I – daily interception, mm day-1; k – dimensionless constant equal to 3.6 10-5; -1 K1 – maximum value of saturated hydraulic conductivity, m s ; -1 Kij – hydraulic conductivity tensor, i, j = 1, 2, m s ; -1 Ks – saturated hydraulic conductivity, m s ; l – fitting parameter, l = 0.5; L – soil sample height, m; Ld – length of the dry soil bar, dried at 105 C degree, m; LL – liquid limit, %; 5 LS – linear shrinkage indicator, %; Lw – length of the wet soil bar, m; n, m – dimensionless water retention curve fitting parameters, m = 1-n-1; -1 Pcorr – corrected daily precipitation, mm day ; PI – plasticity index, %; PL – plastic limit, %; Q – sink or source term, s-1; q – water volumetric flow rate, m3 s-1, q=V/t, V – volume read from burette, m3, t – time, s; -1 qd – daily water flux, mm day ; -1 qD – Darcy unit flux, m s ; -1 qi – groundwater flux vector, m s ; -1 qrunoff – daily surface runoff, mm day ; rs – dimensionless geometry factor; S – potential swell, %; Sa – actual degree of saturation; Se – dimensionless effective saturation; SL – shrinkage limit, %; Sr – residual degree of saturation; Ss – saturated degree of saturation; 2 -1 Ss – specific surface area, m kg ; t – time, s; 3 Vd – dry soil specimen volume, m ; 3 Vs – saturated soil specimen volume, m ; zd – dry soil specimen height, m; zs – saturated soil specimen height, m. 6 1. Preface Landfilling, limiting the pressure of residual waste on the natural environment, public health, numerous social and economic issues, is the final stage of sustainable municipal solid waste management. The number of active landfills and relative volume of deposited waste vary in different countries of the world. Despite the fact that developed countries limit their application and increase the share of waste reuse and volume reduction processes, landfills are, and will be for many decades, a dominant cost-effective method of final deposition of municipal solid waste in medium- and low-income developing countries. Landfilling is a manner of final waste deposition inside a trench equipped with various
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