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The purpose of this study is to investigate the effect of presence of buried flexible pipe on the bearing capacity of shallow footing. First, a model study is performed where shallow footing model is tested for its load settlement behavior, with and without the existence of buried PVC pipe lying vertically below the base of the footing.

The experimental set-up consisted of a steel box filled with sand at two different relative density values [RD = 50 per cent (medium dense) and RD = 80 per cent (dense sand)] and vertical load was applied on the model footing through hydraulic jack and reaction frame arrangement connected with a proving ring. Test results are verified numerically using commercially available finite element code PLAXIS 2D. With due verification, a parametric study has been conducted, numerically, by varying the range of input parameters, such as unit weight, angle of internal friction, diameter of buried conduit and the Elastic modulus of the soil to assess the pre cent reduction in the capacity of the foundation soil because of the presence of underlying buried flexible pipe.

Results show that for each footing, there exists a critical depth below which the presence of the buried conduit has negligible influence on the footing performance. When the conduit is located above the critical depth, the bearing capacity of the footing varies with various factors, such as geotechnical parameters of soil and location and diameter of the buried conduit.

It is an original paper performed to assess the presence of buried flexible pipe on the bearing capacity of the shallow footing.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

The estimation of bearing capacity for shallow foundations in swelling soil is an important and complex context. The complexity is due to the unsaturated swelling soil related to the drying and humidification environment. Hence, a serious study is needed to evaluate the effect of swelling potential soil on the foundation bearing capacity. The purpose of this paper is to analyze the bearing capacity of a rough square foundation founded on a homogeneous swelling soil mass, subjected to vertical loads.

A proposed numerical model based on the simulation of the swelling pressure in the initial state, followed by an elastoplastic behavior model may be used to calculate the foundation bearing capacity. The analyses were carried out using the finite-difference software (FLAC 3 D) with an elastic perfectly plastic Mohr–Coulomb constitutive model. Moreover, the numerical results obtained are compared with the analytical solutions proposed in the literature.

The numerical results were in good agreement with the analytical solutions proposed in the literature. Also, reasonable capacity and performance of the proposed numerical model.

The proposed numerical model is capable to predict the bearing capacity of the homogeneous swelling soil mass loaded by a shallow foundation. Also, it will be of great use for geotechnical engineers and researchers in the field.

The purpose of this paper is to present several methods on how to deal with yield surface discontinuities. The explicit formulations, first presented by Koiter (1953), result in multisingular constitutive matrices which can cause numerical problems in elasto-plastic finite element calculations. These problems, however, are not documented in previous literature. In this paper an amendment to the Koiter formulation of the constitutive matrices for stress points located on discontinuities is proposed.

First, a review of existing methods of handling yield surface discontinuities is given. Examples of the numerical problems of the methods are presented. Next, an augmentation of the existing methods is proposed and its robustness is demonstrated through footing bearing capacity calculations that are usually considered “hard”.

Previous studies documented in the literature all present “easy” calculation examples, e.g. low friction angles and few elements. The amendments presented in this paper result in robust elasto-plastic computations, making the solution of “hard” problems possible without introducing approximations in the yield surfaces. Examples of “hard” problems are highly frictional soils and/or three-dimensional geometries.

The proposed method makes finite element calculations using yield criteria with corners and apices, e.g. Mohr-Coulomb and Hoek-Brown, much more robust and stable.

The varying traditions, goals, paradigms, and discourses associated with English language arts (ELA) underscore the degree to which there is not one school subject English, but many “Englishes.” In a neoliberal context, where movements like standardization and accountability stake claims about what ELA should be and do in the world, teachers, especially beginning teachers, can struggle to navigate the tensions engendered by these many and contradictory “Englishes.” This chapter attends to this struggle and delineates a process by which English Educators might illustrate the field’s vast and ever-changing terrain and support beginning teachers as they locate themselves in ELA. In delineating this process, we argue that in order to see and navigate the field in a neoliberal era, ELA teachers should treat the field as a discursive construction, constantly re-constructed by the dynamic play of social, political, and economic discourses. We argue that in treating the field as a discursive construction and exploring and locating themselves within the terrain, ELA teachers, rather than feeling powerless in the face of neoliberal forces, can leverage these different discursive forces, and gain footing in their classrooms, schools, and extracurricular communities to navigate the coexistence of many “Englishes” and argue for their pedagogical choices.

Large deformation problems are frequently encountered in various fields of geotechnical engineering. The particle finite element method (PFEM) has been proven to be a promising method to solve large deformation problems. This study aims to develop a computational framework for modelling the hydro-mechanical coupled porous media at large deformation based on the PFEM.

The PFEM is extended by adopting the linear and quadratic triangular elements for pore water pressure and displacements. A six-node triangular element is used for modelling two-dimensional problems instead of the low-order three-node triangular element. Thus, the numerical instability induced by volumetric locking is avoided. The Modified Cam Clay (MCC) model is used to describe the elasto-plastic soil behaviour.

The proposed approach is used for analysing several consolidation problems. The numerical results have demonstrated that large deformation consolidation problems with the proposed approach can be accomplished without numerical difficulties and loss of accuracy. The coupled PFEM provides a stable and robust numerical tool in solving large deformation consolidation problems. It is demonstrated that the proposed approach is intrinsically stable.

The PFEM is extended to consider large deformation-coupled hydro-mechanical problem. PFEM is enhanced by using a six-node quadratic triangular element for displacement and this is coupled with a four-node quadrilateral element for modelling excess pore pressure.

Effective explicit algorithms for integrating complex elastoplastic constitutive models, such as those belonging to the Cam clay family, are described. These automatically divide the applied strain increment into subincrements using an estimate of the local error and attempt to control the global integration error in the stresses. For a given scheme, the number of substeps used is a function of the error tolerance specified, the magnitude of the imposed strain increment, and the non‐linearity of the constitutive relations. The algorithms build on the work of Sloan in 1987 but include a number of important enhancements. The steps required to implement the integration schemes are described in detail and results are presented for a rigid footing resting on a layer of Tresca, Mohr‐Coulomb, modified Cam clay and generalised Cam clay soil. Explicit methods with automatic substepping and error control are shown to be reliable and efficient for these models. Moreover, for a given load path, they are able to control the global integration error in the stresses to lie near a specified tolerance. The methods described can be used for exceedingly complex constitutive laws, including those with a non‐linear elastic response inside the yield surface. This is because most of the code required to program them is independent of the precise form of the stress‐strain relations. In contrast, most of the implicit methods, such as the backward Euler return scheme, are difficult to implement for all but the simplest soil models.

Theoretical modeling on the performance of offshore circular foundation installed on clay and subjected to combined horizontal-vertical load in the Niger Delta has been attempted. Analytical methods of Skempton, Brinch Hanson, and Vesic were used to evaluate concentric vertical loads on offshore piles. Horizontal forces, H were evaluated for varying wave heights on circular piles of 1.0 to 2.0 m diameters using available meteorological and oceanographic offshore records. The results revealed that sliding failure commenced when the ratio of vertical load to footing area and undrained shear strength, V/As_u assumed negative values (i.e. at H > 0.082 As_u). The maximum mean vertical load is 6.107 As_u, and to guide against the occurrence of bearing capacity failure by sliding, V > 0.75H for cases where the ratio of footing depth to breadth ratio is lesser than one, (D/B < 1.0) and V > 0.70H when footing depth to breadth ratio is greater than one (D/B > 1.0).

Study of soil‐structure interaction effect in framed structures necessitates proper physical modelling of the structure, foundation and the soil mass. At the same time, the stress—strain model used for the constitutive relationship of the soil mass must also be realistic. In the present study, a hyperbolic stress—strain model has been used to consider the soil non‐linearity. The interactive behaviour of a five storey, two bay plane frame has been studied in detail and the results are compared with those obtained from a conventional and a linear interactive analysis.

Misunderstanding and harmful stereotyping have become commonplace amongst people in the United States and the Middle East/North Africa (MENA) region since 2001, if not earlier. If universities are the locus of transformative education, work remains towards remedying these issues.One non-profit organisation, “Natafaham (pseudonym, Arabic for « we understand each other”), works to undo this negativity student by student. It brings participants from the MENA and Europe/North America into dialogue via Zoom each week. The inter-cultural dialogue availed to participants is empowering to actors, including the dialogue facilitator. This narrative is an autoethnographic exploration of my experience as an intercultural dialogue facilitator. Yet reviewing contemporaneous notes and reflections revealed structural aspects of this programme that empower voices from the MENA region, while facilitating learning amongst participants on both sides of the Atlantic. Such aspects include the format and the location of the programme, its focus on individuals rather than institutions or groups, its mixed top-down and bottom-up approach, and the opportunities it avails for ascension to positions of authority. This narrative analyses these aspects through several lenses and academic traditions, including those of global citizenship, critical internationalisation, (reciprocal) global service learning, and socio-cultural frameworks of second language acquisition. The chapter urges that these aspects are recognised as key catalysts of (more) equal relationships between youth in the MENA region and the United States, which merit widespread replication. It concludes by envisioning a still more equal relationship predicated upon more equitable language usage.