Study on the engineering characteristics and microstructures of different types of soft clay

Prediction of the as-laid embedment of a pipeline, which affects many aspects of pipeline design, is complicated by the dynamic motions that occur during the lay process. These motions cause pipelines to embed deeper than predicted based on static penetration models, as the seabed soils are both softened and physically displaced by the pipeline motion. This paper describes the results of 2D numerical analyses using a large displacement finite element approach aimed at quantifying pipeline embedment due to cyclic lateral motion at various fixed vertical load levels. The validity of the numerical results is first assessed by comparison with published data from centrifuge model tests in two different types of clay. A parametric study varying the normalized vertical load is then presented, which suggests a simple approach for estimating an upper limit to the dynamic embedment.

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Improvement of Soft Clay Soil Using Different Types of Additives

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/856/1/012010 ◽

2021 ◽

Vol 856 (1) ◽

pp. 012010

Author(s):

Omer A. Abd-Allah ◽

Safa H. Abid Awn ◽

Raquim N. Zehawi

Keyword(s):

Clay Soil ◽

Soft Clay ◽

Different Types

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Experiment and 3D-numerical studies on soft clay bed reinforced with different types of cellular confinement systems

Transportation Geotechnics ◽

10.1016/j.trgeo.2017.01.001 ◽

2017 ◽

Vol 10 ◽

pp. 73-84 ◽

Cited By ~ 25

Author(s):

A. Hegde ◽

T.G. Sitharam

Keyword(s):

Soft Clay ◽

Numerical Studies ◽

Different Types

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1-D CONSOLIDATION OF SOFT CLAY SUBJECTED TO CYCLIC LOADING USING LEM

Malaysian Journal of Civil Engineering ◽

10.11113/mjce.v30n2.482 ◽

2018 ◽

Vol 30 (2) ◽

Cited By ~ 1

Author(s):

Omar El Gendy ◽

Ibrahim El Arabi ◽

Ibrahim El Kersh

Keyword(s):

Cyclic Loading ◽

Initial Stress ◽

Soft Clay ◽

Equation Method ◽

Storage Tanks ◽

Soil System ◽

Consolidation Settlement ◽

Different Types ◽

Degree Of Consolidation ◽

Port Said

In this paper, a numerical modification is carried out on the Layer Equation Method (LEM) of El Gendy and Herrmann to be applicable for analyzing 1-D consolidation of soft clay subjected to cyclic loading. The LEM is applicable for multilayered soil system subjected to variable initial stress along depth. The proposed solution is used for normally and over consolidated clays subjected to different types of cyclic loading considering the basis of the method of Toufigh and Ouria. The LEM is incorporated by the authors into the geotechnical software ELPLA and is verified with two verifications. The results of the verifications are close to the references results. The proposed solution is applied for circular storage tanks as a structure subjected to cyclic loading from filling and discharging cycles. An application was held to study the effect of cyclic loading on two zones located at Port-Said city in Egypt using real soil data from real sites. The results of the average degree of consolidation and consolidation settlement versus time are presented for both zones.

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The extinction time of a general birth and death process with catastrophes

Journal of Applied Probability ◽

10.1017/s0021900200116031 ◽

1986 ◽

Vol 23 (04) ◽

pp. 851-858 ◽

Cited By ~ 1

Author(s):

P. J. Brockwell

Keyword(s):

Laplace Transform ◽

Size Distribution ◽

Sufficient Conditions ◽

Necessary And Sufficient Conditions ◽

Death Process ◽

Extinction Time ◽

Birth And Death Process ◽

Different Types ◽

The Laplace Transform ◽

Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

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Differentiating between different forms of moral obligations

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002589 ◽

2020 ◽

Vol 43 ◽

Author(s):

Rajen A. Anderson ◽

Benjamin C. Ruisch ◽

David A. Pizarro

Keyword(s):

Moral Character ◽

Moral Obligations ◽

Different Types

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053310 ◽

1982 ◽

Vol 40 ◽

pp. 118-119

Author(s):

U. Aebi ◽

P. Rew ◽

T.-T. Sun

Keyword(s):

Electron Microscopy ◽

Structural Organization ◽

Cell Types ◽

Structural Features ◽

Molecular Architecture ◽

The Past ◽

Keratin Filaments ◽

Different Types ◽

10 Nm Filaments ◽

Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

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A New Defect in Polyethylene Single Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070795 ◽

1973 ◽

Vol 31 ◽

pp. 70-71

Author(s):

E. L. Thomas ◽

S. L. Sass

Keyword(s):

Single Crystals ◽

Screw Dislocation ◽

Small Distance ◽

Dipole Model ◽

Dislocation Dipole ◽

Chain Folding ◽

Black And White ◽

Polymer Crystal ◽

Different Types

In polyethylene single crystals pairs of black and white lines spaced 700-3,000Å apart, parallel to the [100] and [010] directions, have been identified as microsector boundaries. A microsector is formed when the plane of chain folding changes over a small distance within a polymer crystal. In order for the different types of folds to accommodate at the boundary between the 2 fold domains, a staggering along the chain direction and a rotation of the chains in the plane of the boundary occurs. The black-white contrast from a microsector boundary can be explained in terms of these chain rotations. We demonstrate that microsectors can terminate within the crystal and interpret the observed terminal strain contrast in terms of a screw dislocation dipole model.

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Methionine-Specific Staining of Collagen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005408x ◽

1982 ◽

Vol 40 ◽

pp. 294-295

Author(s):

E.M. Kuhn ◽

K.D. Marenus ◽

M. Beer

Keyword(s):

Amino Acids ◽

Collagen Fibers ◽

Type Iii Collagen ◽

Type I ◽

Electron Microscopic ◽

Good Correspondence ◽

Specific Staining ◽

Type Iii ◽

Different Types ◽

Sulfur Containing

Fibers composed of different types of collagen cannot be differentiated by conventional electron microscopic stains. We are developing staining procedures aimed at identifying collagen fibers of different types.Pt(Gly-L-Met)Cl binds specifically to sulfur-containing amino acids. Different collagens have methionine (met) residues at somewhat different positions. A good correspondence has been reported between known met positions and Pt(GLM) bands in rat Type I SLS (collagen aggregates in which molecules lie adjacent to each other in exact register). We have confirmed this relationship in Type III collagen SLS (Fig. 1).

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