scholarly journals Research of Consolidation of Water-Saturated Silty-Clay Soils with Vertical Drainage

2018 ◽  
Vol 16 (1) ◽  
pp. 76
Author(s):  
A A Kislyakov ◽  
M A Kislyakov ◽  
N K Simakov
Keyword(s):  
Clay Soils ◽  
Silty Clay ◽  
Vertical Drainage ◽  
Water Saturated

В статье рассматриваются вопросы изучения процессов консолидации водонасыщенных пылевато-глинистых грунтов. Перед исследователями ставилась задача оценки эффективности работы ленточных дрен в водонасыщенных пылевато-глинистых грунтах и определения оптимального расстояния между дренами. Методика проведения полевого эксперимента основывалась на положении о необходимости максимально возможного сохранения природной структуры грунта при установке в нем аппаратуры для исследований. Принят бесконтактный способ определения послойных деформаций грунта с помощью глубинных кольцевых марок и методы определения напряжений мессдозами и датчиками порового давления, которые устанавливались в пробуренные в массиве грунта скважины. Оборудование контрольно-измерительной аппаратурой полигонов с разным шагом дрен, а затем проведение наблюдений на них в сочетании с наблюдениями на полигоне без дрен позволяет оценить эффективность работы ленточных дрен в данных грунтах и определить оптимальное расстояние между дренами.

Study of the Processes of Consolidation of a Thick Mass of Water-Saturated Clay Soils when Erecting Unique Structures

2018 ◽  
Vol 55 (5) ◽  
pp. 333-339 ◽  
Author(s):  
M. Yu. Abelev ◽  
I. V. Averin ◽  
D. Yu. Chunyuk ◽  
O. V. Kopteva
Keyword(s):  
Clay Soils ◽  
Saturated Clay ◽  
Water Saturated

scholarly journals Optimizing the sand cushion

2019 ◽  
Vol 7 (4) ◽  
pp. 32-35
Author(s):  
Vyacheslav Glukhov ◽  
Ol'ga Hryanina ◽  
Svetlana Glukhova ◽  
Anastasia Pugina
Keyword(s):  
Clay Soils ◽  
Construction Site ◽  
Advantages And Disadvantages ◽  
Saturated Clay ◽  
Metal Pipes ◽  
Water Saturated ◽  
Economic Comparison ◽  
Sand Cushion

It is known that the stress values and the distribution of the latter in depth depend to a large extent on the size of the Foundation sole and especially the width. In this article, in order to select the optimal width of the Foundation sole and the thickness of the sand cushion, the influence of the sole width on the distribution of vertical stresses in the ground base is studied on the example of foundations for metal pipes. The presence of weak water-saturated clay soils within the construction site was taken into account. Variants of the device from traditional prismatic piles and foundations of small laying on a sandy pillow are offered. a technical and economic comparison of options was carried out. The advantages and disadvantages of each option are analyzed. Using the methodology of verification calculations in the design of sandbags, the optimization of the accepted version of the foundations was made.

scholarly journals Applicability of wetting front advancing method in the sand to silty clay soils

2020 ◽  
Vol 60 (5) ◽  
pp. 1215-1225
Author(s):  
Qiang Liu ◽  
Ping Xi ◽  
Jiali Miao ◽  
Xiaochen Li ◽  
Ke Wang
Keyword(s):  
Clay Soils ◽  
Silty Clay ◽  
Wetting Front

scholarly journals Microbial biodiversity as related to crop succession and potato intercropping for management of brown rot disease

2019 ◽  
Vol 29 (1) ◽  
Author(s):  
N. A. S. Messiha ◽  
K. M. A. Elhalag ◽  
N. M. Balabel ◽  
S. M. A. Farag ◽  
H. A. Matar ◽  
...  
Keyword(s):  
Sandy Soils ◽  
Brown Rot ◽  
High Ratio ◽  
Fluorescent Pseudomonads ◽  
Clay Soils ◽  
Silty Clay ◽  
Potato Brown Rot ◽  
Rot Disease ◽  
Bacterial Plant Pathogen ◽  
Crop Succession

AbstractPotato brown rot, caused by Ralstonia solanacearum, ranked globally as the second most important bacterial plant pathogen. In the present study, the influence of different cropping programs in potato brown rot management was investigated in four infected fields in Egypt. Two districts were selected as sandy soils in Giza (Wardan) and Behera (Ganuob El-Tahrir) governorates. The other two were selected as silty clay in Minufyia (Talia) and Beni-Suef (Sids) governorates. The followed crop succession included corn, potato intercropped with cabbage, onion, cowpea, wheat, corn again, and ended by potato. The pathogen was undetectable after corn, onion, and wheat. It decreased in cowpea and cabbage rhizospheres in the clay soils. The pathogen was undetectable at all districts, except at Sids, where the pathogen was significantly decreased but was not eradicated. This was possibly attributed to the high ratio of NO3− and Na+ at this district. Decreased R. solanacearum density after corn coincided with the high ratio of fluorescent pseudomonads, endospores, and actinomycetes, being most clear in the poor soils (Wardan) and less clear under iron excess at Ganoub El-Tahrir as well as the clay soils. Corn rhizosphere supported an array of antagonistic actinomycetes such as strains similar to Streptomyces intermedius, Streptomyces albidoflavus group, Streptomyces argenteolus group, and Streptomyces erythrogriseus. Intercropping potato with cabbage decreased the density of the pathogen in rhizosphere, which is associated with greater antagonistic fluorescent pseudomonads, Bacillus spp. and Serratia spp. Onion soil and rhizosphere associated with abundance of antagonists and fluorescent pseudomonads, followed by S. maltophilia and Bacillus spp. Wheat soil and rhizosphere supported fluorescent pseudomonads and antagonistic Streptomyces spp., especially in sandy soils. The pathogen was undetectable after planting the ending potato in the three districts, Wardan, Ganoub El-Tahrir, and Talia. This was accompanied by a general oligotrophism and increased ratio of fluorescent pseudomonads, endospores bacteria, and actinomycetes along with a diversity of R. solanacearum antagonists such as S. maltophilia, Citrobacter freundii, Acinetobacter sp., Delftia sp., and Serratia marcescens.

MEASUREMENT OF FRACTURE MECHANICS PARAMETERS IN SILTY-CLAY SOILS

Soil Science ◽  
1997 ◽  
Vol 162 (5) ◽  
pp. 309-322 ◽  
Author(s):  
J. R. Nichols ◽  
M. E. Grismer
Keyword(s):  
Fracture Mechanics ◽  
Clay Soils ◽  
Silty Clay

SOME OBSERVATIONS ON THE UNDRAINED SHEARING STRENGTH USED TO ANALYZE A FAILURE

1969 ◽  
Vol 6 (2) ◽  
pp. 97-110 ◽  
Author(s):  
F. A. De Lory ◽  
R. J. Salvas
Keyword(s):  
Clay Soils ◽  
Triaxial Tests ◽  
Silty Clay ◽  
Compression Tests ◽  
Foundation Soil ◽  
Shearing Strength

The undrained shearing strength of the foundation soil at the site of a failure of a low embankment was investigated by several methods. It was found that both field vane and laboratory compression tests tended to underestimate the strength required for stability. Further consideration of the test specimens from sample tubes showed the undrained shearing strength varied considerably with the position of the sample in the tube. Specimens from tubes from another site yield the same type of results. The two silty clay soils involved were studied in more detail using CIU and CAU triaxial tests and comparing cu/p′ ratios. It was found that in general they yielded the values usually obtained for lacustrine clays.

CHANGE IN STRENGTH PARAMETERS OF DISPERSED SOILS AFTER HIGH-FREQUENCY VIBRATION

2021 ◽  
Vol 12 (1) ◽  
pp. 46-56
Author(s):  
V. M Polunin ◽  
A. P Cheremhina
Keyword(s):  
High Frequency ◽  
Field Measurements ◽  
Field Studies ◽  
Clay Soils ◽  
Laboratory Studies ◽  
Strength Parameters ◽  
High Frequency Vibration ◽  
Soil Foundation ◽  
Comparison Of The Results ◽  
Water Saturated

The use of the technology of high-frequency sheet piles driving or extraction in conditions of weak, structurally unstable soils inevitably leads to a change in the structure of the soil. This is especially true for buildings which fall into the zone of influence. Often, foundation for historical buildings is water-saturated sands, spread by fluid and fluid-plastic clay soils. In the process of external dynamic action, the soil foundation is been destructing, so their strength and deformation parameters are reduced. In this case, the result of vibration effects on a dispersed water-saturated sample can be both compaction for sandy soil and decompaction of clay soils. These changes lead to additional deformations of buildings and structures of the surrounding area. Therefore, the issue of assessing the limits of applicability of vibration technology in certain conditions is relevant. The object of the study is the changes in the properties of clay soils of various consistencies after exposure to vibration. The results of laboratory studies to determine the strength parameters of dispersed soils after high-frequency vibration are presented. The results of field measurements by CPT "before", "after" vibration immersion and vibration extraction of sheet piles are considered. Comparison of the results of field and laboratory studies is carried out to identify patterns of change in the strength characteristics of weak soils under the influence of vibration loads. A tendency towards a decrease in the strength parameters of dispersed soils is shown. Currently, due to the insufficient number of laboratory and field studies to study the effect of high-frequency vibration on the change in the strength parameters of weak water-saturated clay soils, it is not possible to identify a clear dependence of the change in parameters on the time and frequency of vibration.

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