Darcy flux as hydrological indicator for the swelling potential of clay–sulfate rocks in tunneling

2015 ◽  
Vol 197 ◽  
pp. 11-19 ◽  
Author(s):  
Christoph Butscher ◽  
Herbert H. Einstein ◽  
Peter Huggenberger
Keyword(s):  
Swelling Potential ◽  
Darcy Flux

An Overview: to Reduce Swelling Potential of Expansive Soil By Using Polypropylene Material

2018 ◽  
pp. 129-131
Author(s):  
A. A. Musale ◽  
M. A. Mhetre ◽  
A. I. Mukeri ◽  
K. S. Chavan ◽  
R. N. Kawade ◽  
...  
Keyword(s):  
Expansive Soil ◽  
Swelling Potential ◽  
Polypropylene Material

scholarly journals The convection of a Bingham fluid in a differentially-heated porous cavity

2016 ◽  
Vol 26 (3/4) ◽  
pp. 879-896 ◽  
Author(s):  
D. Andrew S. Rees
Keyword(s):  
Rayleigh Number ◽  
Yield Stress ◽  
Piecewise Linear ◽  
Rectangular Cavity ◽  
Content Type ◽  
Multigrid Algorithm ◽  
Bingham Number ◽  
Steady Solutions ◽  
Darcy Flux ◽  
Darcy Rayleigh Number

Purpose – The purpose of this paper is to determine the manner in which a yield stress fluid begins convecting when it saturates a porous medium. A sidewall-heated rectangular cavity is selected as the testbed for this pioneering work. Design/methodology/approach – Steady solutions are obtained using a second order accurate finite difference method, line relaxation based on the Gauss-Seidel smoother, a Full Approximation Scheme multigrid algorithm with V-cycling and a regularization of the Darcy-Bingham model to smooth the piecewise linear relation between the Darcy flux and the applied body forces. Findings – While Newtonian fluids always convect whenever the Darcy-Rayleigh number is nonzero, Bingham fluids are found to convect only when the Darcy-Rayleigh number exceeds a value which is linearly dependent on both the Rees-Bingham number and the overall perimeter of the rectangular cavity. Stagnation is always found in the centre of the cavity and in regions close to the four corners. Care must be taken over the selection of the regularization constant. Research limitations/implications – The Darcy-Rayleigh number is restricted to values which are at or below 200. Originality/value – This is the first investigation of the effect of yield stress on nonlinear convection in porous media.

Closure to “Prediction of Swelling Potential for Compacted Clays”

1963 ◽  
Vol 89 (3) ◽  
pp. 143-146
Author(s):  
H. B. Seed ◽  
Jr. Woodward ◽  
R. Lundgren
Keyword(s):  
Swelling Potential ◽  
Compacted Clays

scholarly journals KAJIAN PERBAIKAN SUBGRADE DARI TANAH EKSPANSIF MENGGUNAKAN SPENT CATALYST RCC 15 DAN ABU BATOK KELAPA SAWIT

2016 ◽  
Vol 18 (2) ◽  
Author(s):  
Totok Hermawan ◽  
Syahril Syahril
Keyword(s):  
Swelling Pressure ◽  
Plasticity Index ◽  
Swelling Potential ◽  
Spent Catalyst

Hasil pengujian pada lapisan Subgrade yang dilakukan di ruas jalan tol Cisumdawu khususnya pada STA 13+500 tergolong pada jenis tanah ekspansif. Kondisi Subgrade tersebut jika tidak segera diperbaiki maka dapat mengakibatkan berbagainya jenis kerusakan pada perkerasannya. Dalam penelitian perbaikan Subgrade yang dilakukan adalah menggunakan metode stabilisasi dengan Abu Batok Kelapa Sawit dan Spent Catalyst RCC 15. Penelitian ini bertujuan untuk mengevaluasi sejauh mana pengaruh penambahan Abu Batok Kelapa Sawit dan Spent Catalyst RCC 15 terhadap kembang susut dan daya dukung sebagai lapisan Subgrade konstruksi perkerasan ruas jalan tol Cisumdawu. Penelitian ini menghasilkan beberapa kesimpulan yaitu (1) Terjadi  penurunan nilai untuk kadar air optimum, Plasticity Index, Swelling Potential dan Swelling Pressure. (2) Terjadi Kenaikan nilai untuk Berat Isi Kering, CBR Unsoaked, CBR Soaked, CBR Peram, Permeabilitas, Ca-dd dan K-dd. (3) Tercapainya campuran bahan stabilisasi yang dapat digunakan sebagai perbaikan Subgrade pada tanah ekspansif untuk standar minimal Subgrade lapisan perkerasan jalan. (4) Belum tercapainya nilai yang optimum pada campuran bahan stabilisasi yang digunakan terhadap perubahan nilai karakteristik Subgrade. (5) Hasil pengujian secara statistik yang dilakukan didapatkan suatu hubungan yang yang berarti secara statistic.

scholarly journals Multifunctional Semi-interpenetrating Superabsorbents from Graft Polymerization of Acrylic Acid on Cellulose in Presence of Fulvic Acid as Potential Slow Release Devices of Soil Nutrients

2016 ◽  
Vol 12 (2) ◽  
pp. 4045-4056 ◽  
Author(s):  
Hisham Essawy
Keyword(s):  
Acrylic Acid ◽  
Soil Nutrients ◽  
Network Structure ◽  
Water Retention ◽  
Graft Polymerization ◽  
Morphological Alteration ◽  
Interpenetrating Network ◽  
Swelling Potential ◽  
Additional Advantage ◽  
Release Devices

Grafting polymerization of acrylic acid (AA) was undertaken onto cellulose powder (Cell) in presence of potassium fulvate (KF) to produce semi-interpenetrating network structures. The grafting efficiency (GE) and grafting yield (GY) were studied as and indicated that the grafting process was not influenced in presence of KF. KF was expected to be incorporated into the cellulose backbone in the same course of the graft polymerization via polycondensation with groups from cellulose and monomer. The simultaneous graft polymerization of acrylic acid and polycondensation processes of all components allows formation of a more chemically active semi-interpenetrating network structure. Successful incorporation of KF to the network structure was predicted from fourier transform infrared spectroscopy (FTIR) while enhanced Cu2+ uptake confirmed the better chemical activity with respect to the same network prepared in absence of KF. Furthermore, the wide variation of the swelling potential as a function of the pH further corroborates the insertion of KF to the network structure. Imaging with scanning electron microscopy (SEM) indicated morphological alteration on the surface which might be related to the KF anchoring to the cellulose backbone. The developed superabsorbents showed increment in the water absorption both in distilled water and salted solutions as well. The newly developed superabsorbent was applied as a support for soil nutrients and their controlled release in soil was studied. The results proved efficiency of the superabsorbent to warrant appropriate release of the nutrients according to the time regulations set by European Committee of Normalization (ECN). Improved water retention was also an additional advantage.

scholarly journals The Use of Geogrids in Mitigating Pavement Defects on Roads Built over Expansive Soils

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Richard Shumbusho ◽  
Gurmel S. Ghataora ◽  
Michael P.N. Burrow ◽  
Digne R. Rwabuhungu
Keyword(s):  
Seasonal Changes ◽  
Expansive Soils ◽  
Expansive Soil ◽  
Real Field ◽  
Experimental Program ◽  
Swelling Potential ◽  
Swelling Behaviour ◽  
Wetting And Drying ◽  
Potential Benefits

This study was conducted to investigate the potential benefits of using geogrids in mitigating pavement defects notably roughness and longitudinal cracking on pavements built over expansive soils. The seasonal changes of expansive soils (periodic wetting and drying) cause detrimental effects on the overlying road pavements. Such detrimental behavior of expansive soils was simulated in a controlled laboratory environment through allowing cyclic wetting and drying of an expansive soil underlying a pavement section. The shrink/swell effects of the expansive soil subgrade were examined through monitoring its change in moisture, and measuring deformation of overlying pavement section. The experimental study suggested that a geogrid layer in a reinforced pavement section can reduce surface differential shrinking and swelling deformation resulting from underlying expansive soils by a factor of 2 and 3 respectively in comparison to unreinforced section. Given that an oedometer test which is typically used to predict swelling potential of expansive soils is known to overpredict in-situ soil swell, experimental program also investigated quantitatively the extent to which the oedometer can overestimate swelling behaviour of the real-field scenarios. It was found that oedometer percent swell can overpredict in-situ swelling behaviour of the expansive soil by a factor ranging between 2 and 10 depending upon the period over which the in-situ expansive soil has been in contact with water.

Stabilization of clayey subgrade with waste pumice for road infrastructure

2015 ◽  
Vol 22 (5) ◽  
Author(s):  
Ömür Çimen ◽  
Mehmet Saltan ◽  
S. Nilay Keskin
Keyword(s):  
Mechanical Properties ◽  
Road Construction ◽  
High Plasticity ◽  
Test Results ◽  
Index Properties ◽  
Compression Tests ◽  
Unconfined Compression ◽  
Swelling Potential ◽  
Project Costs ◽  
High Plasticity Clay

AbstractHigh-plasticity clayey subgrade, which is unsuitable for road construction, may sometimes occur along highway routes. In such cases, engineers need to change the route of a highway project, resulting in an increase in road length and project costs. In this study, waste pumice was examined for stabilization of high-plasticity clayey subgrade, which is inappropriate for road construction. For this purpose, the physical and index properties of clay and pumice were determined. Then, the pumice was mixed with high plasticity clay at different ratios by weight. By performing standard Proctor compaction tests on the mixtures, the effects of adding pumice on compaction were also studied. Unconfined compression tests and California bearing ratio (CBR) tests were performed on all pumice-clay mixtures, and the test results and the CBR ratios were compared for each sample, respectively. The results showed that pumice stabilization improved the mechanical properties and reduced the swelling potential of high plasticity clayey subgrade.

Backfill of Radioactive Waste Disposal: Feasibility Study of Argillite/Bentonite (COx/MX80) Pellets

2021 ◽  
Author(s):  
Danai Tyri ◽  
Bui Quoc Huy Ly ◽  
François Nader ◽  
Irini Djeran-Maigre ◽  
Jean-Claude Robinet ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
Mechanical Response ◽  
Raw Materials ◽  
Radioactive Waste Disposal ◽  
Maximum Diameter ◽  
Optimal Conditions ◽  
Swelling Potential ◽  
Deep Geological Disposal ◽  
In The Beginning ◽  
Influential Parameters

Abstract A pelletized solution composed of COx argillite and MX80 bentonite is examined as backfill for the deep geological disposal of radioactive waste (Cigeo project). The implementation is studied in terms of installation and hydration conditions as well as their influence on the hydro-mechanical behavior of the mixture. In the beginning, the optimum grain size distribution (GSD) of pellets assembly is determined to minimize initial voids. A series of DEM simulations on ternary samples made of spheres is carried out, investigating the optimal conditions in terms of sizes and proportions. Density maximization occurs when maximum diameter is the dominant size, while minimum and medium diameters are following. As optimum GSD, sizes of 16 mm, 10 mm and 4 mm in 60%, 10% and 30% respectively are chosen. The pelletization of the selected sizes is optimized using an adapted tablet machine to carry out the pellet fabrication. A detailed analysis of influential parameters related to the machine accessories and the inserted raw materials is presented. After modifications, quasi-spherical pellets presenting density of at least 1.95 Mg/m3 are produced. COx/MX80 pellets hydro-mechanical response is indirectly assessed by studying the swelling potential of COx/MX80 powdered mixtures at equivalent emplaced densities. The influence of density, stress and MX80 content on swelling is obtained.

scholarly journals Effect of gypsum content on unsaturated engineering properties of clayey soil

2020 ◽  
Vol 9 (1) ◽  
pp. 84
Author(s):  
Mohammed N J Alzaidy
Keyword(s):  
Shear Strength ◽  
Clayey Soil ◽  
Engineering Properties ◽  
Water Retention Curve ◽  
Shear Strength Parameters ◽  
Swelling Potential ◽  
Soil Water Retention Curve ◽  
Strength Parameters ◽  
Gypsum Content ◽  
Vapour Diffusion

Many of gypsum soils have existed in arid and semi-arid lands. It is considered one of the most problematic soils because of its complicated and unpredicted behavior when exposure to moisture. Extensive researches have been conducted in Iraq to observe the behavior of such soil and to suggest safety restrictions for the collapse and set practical precautions for the structures. This study investigated the effect of gypsum content on some unsaturated engineering properties of a clayey soil. Three different proportions of gypsum (0%, 5% and 20% by weight of the parent soil) were added and tested. The samples have been subjected to swelling potential test, soil water retention curve (SWRC), vapour diffusion and shear strength parameters. It is observed that gypsum content has a significant influence on SWRC, whereas, soil that has high gypsum content made SWRC with higher variables represented by air entry values and residual state. On the other hand, an increase in gypsum content led to a reduction of swelling potential and shear strength parameters. The results of vapour diffusion indicate that gypsum content could modify the microstructure in an unsaturated state and reduce the vapour diffusion through the soil.  

Sign in / Sign up

Export Citation Format

Share Document