Winkler Solution for Seismic Earth Pressures Exerted on Flexible Walls by Vertically Inhomogeneous Soil

Scott J. Brandenberg; Maria Giovanna Durante; George Mylonakis; Jonathan P. Stewart

doi:10.1061/(asce)gt.1943-5606.0002374

Measurement of earth pressures by means of the flat jack test

Open-File Report ◽

10.3133/ofr5431 ◽

1953 ◽

Author(s):

P. Habib ◽

R. Marchand ◽

Severine Britt

Keyword(s):

Earth Pressures

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Geomechanical Behaviour of Uncemented Expanded Polystyrene (EPS) Beads–Clayey Soil Mixtures as Lightweight Fill

Geotechnics ◽

10.3390/geotechnics1010003 ◽

2021 ◽

Vol 1 (1) ◽

pp. 38-58

Author(s):

Pouyan Abbasimaedeh ◽

Ali Ghanbari ◽

Brendan C. O’Kelly ◽

Mohsen Tavanafar ◽

Kourosh Ghaffari Irdmoosa

Keyword(s):

Clayey Soil ◽

Expanded Polystyrene ◽

Environmental Cost ◽

Dry Density ◽

Engineering Practice ◽

Clayey Sand ◽

Earth Pressures ◽

Lightweight Fill ◽

Soil Foundation ◽

Geotechnical Testing

Lightweight fill can be advantageous in embankment construction for the purposes of reducing the (i) bearing pressures on the underlying soil foundation, (ii) destabilizing moments for constructed earthen slopes, and (iii) earth pressures acting behind retaining walls. This paper investigates the merits/limitations of particulate expanded polystyrene (EPS) beads mixed with clayey sand (CS) soil as lightweight fill, considering both geotechnical and environmental perspectives. The bench-scale geotechnical testing programme included standard Proctor (SP) compaction, California bearing ratio (CBR), direct shear (sheardox), oedometer and permeability testing performed on two different gradation CS soils amended with 0.5, 1.5 and 3.0 wt.% EPS, investigating two nominal bead sizes equivalent to poorly-graded medium and coarse sands. Compared to the unamended soils, the compacted dry density substantially decreased with increasing EPS beads content, from 2.09 t/m3 (0 wt.% EPS) to as low as 0.33 t/m3 for 3 wt.% (73 v.%) of larger-sized EPS beads. However, from analyses of the test results for the investigated 50 to 400 kPa applied stress range, even 0.5 wt.% (21 v.%) EPS beads caused a substantial mechanical failure, with a drastic decay of the CBR and compressibility parameters for the studied CS soils. Given the more detrimental environmental cost of leaving myriads of separate EPS beads mixed forever among the soil, it is concluded that the approach of adding particulate EPS beads to soils for producing uncemented lightened fill should not be employed in geotechnical engineering practice.

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The Principle of Effective Stress Theory Research Based on Channel Rate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.336 ◽

2013 ◽

Vol 275-277 ◽

pp. 336-342

Author(s):

Xiao Feng Wu ◽

Guang Fan Li ◽

Wan Cheng He

Keyword(s):

Effective Stress ◽

Permeability Coefficient ◽

Cohesive Soil ◽

Stress Equation ◽

Jump Problem ◽

Stress Theory ◽

Conventional Calculation ◽

Earth Pressures ◽

Stress Surface ◽

Theory Research

Based on the debate of effective stress principle applicability on cohesive soil in recent years and the predecessor's research achievements, this paper puts forward the idea that the effective stress surface including hydrated film surrounding soil particles. And we obtained the extended soil effective stress equation by establishment of the model of channel rate.Combined with the physical significance of permeability coefficient and substantial experimental data, it can establish the fitting equation between permeability coefficient and new proposed physical parameter channel rate. A new calculation method to unify the separate calculation and combined calculation of water and earth pressures is proposed to carry out the transition between results of the two conventional calculation methods and provide a new idea for solving the jump problem between the two results.

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Convective Heat/Mass Transfer Analysis on Johnson-Segalman Fluid in a Symmetric Curved Channel with Peristalsis: Engineering Applications

Symmetry ◽

10.3390/sym12091475 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1475

Author(s):

Humaira Yasmin ◽

Naveed Iqbal ◽

Aiesha Hussain

Keyword(s):

Newtonian Fluid ◽

Peristaltic Flow ◽

Weissenberg Number ◽

Concentration Profiles ◽

Convective Conditions ◽

Curved Channel ◽

Regular Perturbation ◽

Flexible Walls ◽

Physical Level ◽

Parameter Values

The peristaltic flow of Johnson–Segalman fluid in a symmetric curved channel with convective conditions and flexible walls is addressed in this article. The channel walls are considered to be compliant. The main objective of this article is to discuss the effects of curvilinear of the channel and heat/mass convection through boundary conditions. The constitutive equations for Johnson–Segalman fluid are modeled and analyzed under lubrication approach. The stream function, temperature, and concentration profiles are derived. The analytical solutions are obtained by using regular perturbation method for significant number, named as Weissenberg number. The influence of the parameter values on the physical level of interest is outlined and discussed. Comparison is made between Jhonson-Segalman and Newtonian fluid. It is concluded that the axial velocity of Jhonson-Segalman fluid is substantially higher than that of Newtonian fluid.

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Earth pressures exerted on an induced trench cast-in-place double-cell rectangular box culvert

Canadian Geotechnical Journal ◽

10.1139/t2012-093 ◽

2012 ◽

Vol 49 (11) ◽

pp. 1267-1284 ◽

Cited By ~ 22

Author(s):

Olajide Samuel Oshati ◽

Arun J. Valsangkar ◽

Allison B. Schriver

Keyword(s):

Earth Pressure ◽

Test Results ◽

Overburden Pressure ◽

Centrifuge Testing ◽

Geotechnical Centrifuge ◽

Drag Forces ◽

Field Instrumentation ◽

Earth Pressures ◽

Box Culvert ◽

Base Contact

Earth pressure data from the field instrumentation of a cast-in-place reinforced rectangular box culvert are presented in this paper. The instrumented culvert is a 2.60 m by 3.60 m double-cell reinforced cast-in-place rectangular box buried under 25.10 m of fill constructed using the induced trench installation (ITI) method. The average earth pressure measured across the roof was 0.42 times the overburden pressure, and an average of 0.52 times the overburden pressure was measured at mid-height of the culvert on the sidewalls. Base contact pressure under the rectangular box culvert was also measured, providing field-based data demonstrating increased base pressure resulting from downward drag forces developed along the sidewalls of the box culvert. An average increase of 25% from the measured vertical earth pressures on the roof plus the culvert dead load (DL) pressure was calculated at the culvert base. A model culvert was also tested in a geotechnical centrifuge to obtain data on earth pressures at the top, sides, and base of the culvert. The data from the centrifuge testing were compared with the prototype structure, and the centrifuge test results agreed closely with the measured field prototype pressures, in spite of the fact that full similitude was not attempted in centrifuge testing.

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