The properties of clean sands pertaining to shear strength and stiffness have been studied extensively. However, natural generally contain significant amounts silt and/or clay. mechanical response such soils is different from that sands. This paper addresses the effects nonplastic fines on small-strain A series laboratory tests was performed samples Ottawa sand with content in range 5–20% by weight. were prepared at relative densities subjected various levels mean effective consolidation...

Class F fly ash and bottom are the solid residue byproducts produced by coal-burning electric utilities. They usually disposed of together as a waste in utility disposal sites with typical rate 80% 20% ash. Direct use these materials construction projects consuming large volumes materials, such highway embankment construction, not only provides promising solution to problem, but also an economic alternative traditional materials. Representative samples class were collected from two power...

Determination of interface shear strength is crucial in the design many geotechnical structures. To study effect roughness, particle geometry (size and shape), sand gradation on friction angle, direct tests were performed for 10 sands with varying sizes, shapes, gradations four steel surfaces different levels rusting. When sheared along same interface, angle was greater smaller sizes more angular or elongated shapes. For a given sand, increases increasing surface roughness. uniform size,...

The growing interest in utilizing waste materials civil engineering applications has opened the possibility of constructing reinforced soil structures with unconventional backfills. Scrap tires are a high-profile material for which several uses have been studied, including use shredded as backfill. A triaxial testing program was conducted to investigate stress-strain relationship and strength tire chips mixture sand chips. test results additional information from literature were used...

A theory, based on cavity expansion and stress rotation analyses, is developed for computing the cone penetration resistance of sand. The sand modeled as a nonlinear elastic-plastic material. theory can be used analysis calibration chamber tests, it takes full account size boundary conditions. was to calculate values conditions corresponding each about 400 tests performed in different chambers. diameters range from 0.76 1.20 m penetrometer 1 3.57 cm. samples were prepared sands at densities...

It is known that the distribution of active earth pressure against a translating rigid wall not triangular but nonlinear, owing to arching effects in backfill. In present paper, new formulation proposed for calculating on retaining undergoing horizontal translation. takes into account occur backfill (or retained soil mass). order check accuracy formulation, predictions from equation are compared with both existing full-scale test results and values equations. The comparisons between...

This paper compares conventional limit-equilibrium results with rigorous upper and lower bound solutions for the stability of simple earth slopes. The bounding presented in this are obtained by using two newly developed numerical procedures that based on finite-element formulations theorems limit analysis linear programming techniques. Although is used widely practice estimating slopes, its use may sometimes lead to significant errors as both kinematic static admissibility violated method....

Both the driving response and static bearing capacity of open-ended piles are affected by soil plug that forms inside pile during driving. In order to investigate effect on dynamic an load pipe in general, field tests were performed instrumented open- closed-ended driven into sand. For pile, length was continuously measured driving, allowing calculation incremental filling ratio for pile. The cumulative hammer blow count 16% lower than limit unit shaft resistance base 51 32% corresponding...

This paper presents the results of a systematic laboratory investigation on static behavior silica sand containing various amounts either plastic or nonplastic fines. Specimens were reconstituted using new technique suitable for element testing homogeneous specimens sands fines deposited in water (e.g., alluvial deposits, hydraulic fills, tailings dams, and offshore deposits). The fabric was examined environmental scanning electron microscope (ESEM). Static, monotonic, isotropically...

Sand dilates with shearing at a rate that increases increasing relative density (DR) and decreases effective confining stress (σc′). The peak friction angle of sand depends on its critical-state dilatancy. In this paper, we develop simple correlation between angle, dilatancy based triaxial compression plane-strain test data for range pressures from very low levels to approximately 196 kPa.

Bearing capacity calculations are an important part of the design foundations. Most terms in bearing equation, as it is used today practice, empirical. Shape factors for square and rectangular footings could not be derived past because three-dimensional computations performed with any degree accuracy. Likewise, depth determined rigorous analyses foundations embedded ground were available. In this paper, capacities strip, square, circular clay rigorously based on finite element limit...

The finite element method is used for the determination of collapse load a rigid strip footing placed on uniform layer purely frictional soil subjected to inclined and eccentric loading. set free surface mass with no surcharge applied. assumed be elastic – perfectly plastic following Mohr–Coulomb failure criterion. Two series analyses were performed, one using an associated flow rule nonassociated rule. first in accordance bearing capacity solutions currently shallow foundation design...

The paper examines, using numerical modelling, the problem of limit shaft resistance non-displacement piles installed in sands. modelling makes use an advanced, two-surface-plasticity constitutive model. model predicts soil response both small- and large-strain range, while taking into account effects intermediate principal effective stress inherent anisotropy sand. Finite element analyses shearing along pile are performed order to examine development unit changes state around upon axial...

The problem of cone penetration, particularly deep remains one the most challenging in geotechnical engineering. It involves large displacements, rotations and deformation soil elements path as well complex response soil, including crushing development mean stresses, to displacements imposed by penetration process. As a result, rigorous theoretical solutions are not available for this problem, experimental simulations provide insights that would otherwise be available. This paper presents...

This paper presents the results of axial load tests performed on instrumented model piles pre-installed in a large-scale, half-circular chamber with viewing window its flat-side wall. Uniform silica sand samples were prepared different densities using dry pluviation. The effects pile surface roughness and soil density response during loading studied by analysing sequences digital images image correlation technique. Test show that extent zone next to is affected increases as increase....

This paper presents the results of tensile load tests performed with instrumented model piles different surface roughnesses jacked into sand samples in a half-circular calibration chamber digital image correlation (DIC) capability. Digital images and were taken during each test; processing these using DIC technique yielded soil displacement strain fields sand. Data from local sensors show that an increase roughness shaft average unit resistance displacements strains next to pile. Guidance is...

Liquefaction of granular soil deposits is one the major causes loss resulting from earthquakes. The accuracy in assessment likelihood liquefaction at a site affects safety and economy design. In this paper, curves cyclic resistance ratio (CRR) versus cone penetration test (CPT) stress-normalized qc1 are developed combination analysis laboratory testing. approach consists two steps: (1) determination CRR as function relative density triaxial tests performed on samples isotropically...

The bearing capacity of open-ended piles is affected by the degree soil plugging, which quantified incremental filling ratio (IFR). There not at present a design criterion for that explicitly considers effect IFR on pile load capacity. In order to investigate this effect, model tests were conducted instrumented using calibration chamber. results these show increases with increasing relative density and horizontal stress. It can also be seen linearly plug length (PLR) estimated from PLR. unit...

Advances in the design of axially loaded piles are desirable because significant cost savings may result. Well-designed settle by amounts that well tolerated superstructure and induce strains around pile base far removed from failure. To investigate development resistance for a given soil condition increasing settlements, embedded sand modeled using finite-element method with nonlinear elastic-plastic model. Based on load-settlement response obtained analysis cone penetration cavity...

Calibration chamber tests provide an effective way to study cone penetration resistance in sands under controlled conditions. are performed large soil samples with known densities, consolidated desired stresses, and subjected boundary Results from calibration can be used establish the relationship between resistance, density, stress state. However, measured a differs that free field because of size condition effects. There has been considerable uncertainty about these effects, precluding use...

A cavity expansion-based theory for calculation of cone penetration resistance qc in sand is presented. The includes a completely new analysis to obtain from limit pressure. In order more clearly link the proposed with classical expansion theories, which were based on linear elastic, perfectly plastic soil response, equivalent values Young's modulus, Poisson’s ratio and friction dilatancy angles are given charts as function relative density, stress state, critical-state angle. These...

Bearing capacity calculations are an important part of the design foundations. Many terms in bearing equation, as it is used today practice, empirical. Shape factors could not be derived past because three-dimensional computations performed with any degree accuracy. Likewise, depth determined rigorous analyses foundations embedded ground were possible. In this paper, strip, square, circular and rectangular sand for frictional soils following associated flow rule using finite-element limit...