scholarly journals Ultimate Lateral Load Capacity of Piles in Soils Contaminated with Industrial Wastewater

2018 ◽  
Vol 4 (3) ◽  
pp. 509 ◽  
Author(s):  
Mahdi O Karkush ◽  
Mahmoud S Abdul Kareem ◽  
Mustafa M Jasim

The present study devoted to determine the ultimate lateral carrying capacity of piles foundation in contaminated clayey soils and subjected to lateral cyclical loading. Two methods have been used to calculate the lateral carrying capacity of piles foundation; the first one is two-line slopes intersection method (TLSI) and the second method is a modified model of soil degradation. The model proposed by Heerama and then developed by Smith has been modified to take into consideration the effects of heavy loads and soil contamination. The ultimate lateral carrying capacity of single pile and piles group (2×2) driven into samples of contaminated clayey soils have been calculated by using the two methods. Clayey soil samples are contaminated with four percentages of industrial wastewater (10, 20, 40 and 100) % of the distilled water used in the soaking process, the soaking procedure of soil samples have been proceeded for 30 days. Also, two ratios of eccentricity to embedded length (e/L = 0.25 and 0.5) have been examined. The results obtained from two analytical methods are well agreed with those obtained experimentally. The ultimate lateral carrying capacity, Pu (analytical) /Pu (experimentally) ranged from (75-8) % and (77-80) % of single pile with e/L = 0.25 and 0.5 respectively. In the piles group the ratio ranged (67-80) % and (71-79) % for e/L = 0.25 and 0.5 respectively.

2019 ◽  
Vol 9 (1) ◽  
pp. 64-73
Author(s):  
Ferzand K. Medhat ◽  
Mehmet Carpuzcu ◽  
Ali Firat Cabalar ◽  
Ahmed Al-Obaidi

This study presents the effect of Kawergosk refinery waste oil on the geotechnical properties of Erbil clayey soils. A comparison of laboratory test results on uncontaminated clayey soils has been presented and examined. Refinery waste oil of Kawergosk (20 km west of Erbil city) was chosen as the contaminant. A disturbed soil samples were collected from the site which are remolded in the laboratory before each test to represent the field dry density (1.4 gm/cm3, 5.6% water content). Laboratory investigations were carried out on soil samples with 5%, 10%, 15%, and 20% of the waste oil, the results showed a considerable effect on the chemical soil characteristics, while a slight increase of the values of Atterberg limits was observed. A considerable effect on the values of one-dimensional consolidation test parameters has also been observed; the same observation has been seen for the values of direct shear test parameters. A reduction on the values of conductivity coefficient, K has been noticed with increase of contaminated percentage.


2016 ◽  
Vol 6 (1) ◽  
pp. 917-922 ◽  
Author(s):  
M. O. Karkush

The behavior of single piles driven into contaminated clayey soil samples subjected to a combination of static axial and cyclic lateral loadings have been studied in this research. A laboratory model was manufactured especially for studying such behavior. A solid circular cross sectional area pile of diameter 19 mm and made from aluminum, the pile was embedded into the soil with an eccentricity to embedded length (e/L) ratio of 0.334. The intact soil samples and industrial wastewater were obtained from the center of Iraq. The industrial wastewater is a byproduct disposed from Musayib thermal electric power plant. The intact clayey soil samples were synthetically contaminated with four percentages of 10, 20, 40 and 100% from the weight of water used in the soaking process which continued for a period of 30 days. The different percentages of contaminant concentrations have significant effects on the lateral load-displacement relation of the piles subjected to a combination of axial and lateral loadings. The vertical displacement under the same vertical load increased by 5–95%, the axial strength of piles decreased by 10–34% and the lateral-bearing capacity of the piles decreased by 10–34% with increasing the percentage of contamination from 10 to 100%. The ratio of permanent lateral displacement to the total lateral displacement was increased by 23–27% when the concentration of contaminant increased by 10-100%. Generally, the application of axial loading increases the lateral-bearing capacity of piles, and reduces the total lateral displacement.


2017 ◽  
Vol 63 (1) ◽  
pp. 47-62 ◽  
Author(s):  
M. O. Karkush ◽  
T. A. A. Al-Taher

Abstract The impacts of industrial wastewater contamination on the geotechnical properties of clayey soil have been studied in the research presented in this paper. The contaminant in question is industrial wastewater released from Thi-Qar oil refinery as a by-product of production, and the soil samples obtained from Thi-Qar oil refinery plant in Al-Nassyriah (a city located in the south of Iraq). The geotechnical properties of contaminated soil samples were compared with those of intact soil to measure the effects of such a contaminant. The soil samples were obtained from three locations in the study area; representing the highly contaminated area, the slightly contaminated area, and the intact area used as a reference for comparison of test results. The results of the tests showed that the contaminant causes an increase of natural moisture content, field unit weight, Atterberg’s limits, and maximum dry unit weight, as well as an increase of the compression index and the coefficient of vertical consolidation. Also, the contaminant causes a decrease in specific gravity, the optimum moisture content initial void ratio, the swelling index, the coefficient of permeability, and cohesion between soil particles.


2011 ◽  
Vol 71-78 ◽  
pp. 4194-4198
Author(s):  
Shao Qin Zhang ◽  
Hua Hu Cheng

Statically indeterminate frame, composed of beams and columns, is a widely used structure form in civil engineering. The frame carrying capacity under various actions is related to the absolute stiffness of frame components and relative beam-column line stiffness ratio. The matrix displacement method and programming based on MATLAB were employed in this study to calculate the internal forces and displacements of a 2-bay 2-story frame structure under the action of horizontal loads. The influence of the beam-column line stiffness ratio on the frame load capacity was discussed based on the calculated result. Furthermore some advises were provided about the reasonable beam-column line stiffness ratio for engineering design.


2020 ◽  
Vol 44 (3) ◽  
pp. 151-158
Author(s):  
S. Tomilov

Так как в настоящее время в эксплуатации находится достаточно много автодорожных мостов, запроектированных и построенных в различные периоды, их, как и всю дорожную сеть, необходимо поддерживать в состоянии, соответствующем нормативам, а для этого проводить ремонт с использованием элементов усиления несущих конструкций. При качественном возведении и надлежащем уходе высокая степень сохранности мостов позволяет продлить срок их службы путем решения ряда конструктивных вопросов, наиболее актуальным из которых считают обеспечение нормативной грузоподъемности. Усиление с целью повышения грузоподъемности эксплуатируемых мостов достигается путем добавления элементов внешних или внедренных в состав существующего конструктива в зависимости от типа сооружения, его состояния и доступной технологии производства. Однако не только грузоподъемность, но и подверженность конструкций деформациям определяет транспортно-эксплуатационные параметры сооружения, характеризующие послеремонтное состояния моста. Цель настоящего исследования – анализ известного и широко востребованного способа усиления железобетонных балок внешним армированием как обеспечивающего минимальное вмешательство в существующие основные конструкции, технологичного и доступного в исполнении. Впервые дана оценка влияния стадийности включения в работу элементов усиления на общие деформации – прогибы главных балок. Ключевые слова: главная балка, грузоподъемность, усиление, внешняя арматура, свободная затяжка, стадийность работы, относительная деформация, прогиб. Currently, there are quite a lot of road bridges in operation, designed and built in different periods. It is necessary to maintain the road network including bridge structures in a condition that meets up-to-date standards, and for this repair should be carried out using reinforcing elements of the supporting structures. With high-quality construction and proper maintenance, a high degree of safety of bridges allows to extend their service life by solving a number of design issues, the most important of which is considered to be the provision of standard load capacity. Strengthening in order to increase the carrying capacity of operated bridges is achieved by adding elements external or incorporated into the existing structure, depending on the type of structure, its condition and available production technology. However, not only the carrying capacity, but also the susceptibility of structures to deformations determines the transport and operational parameters of the structure, which characterize the post-repair state of the bridge. The purpose of this study is to analyze the well-known and widely demanded method of reinforcing reinforced concrete beams with external reinforcement as providing minimal interference with the existing basic structures, technological and affordable in execution. For the first time, an assessment of the influence of the staging of the inclusion of reinforcement elements in the work on the general deformations – deflections of the main beams. Keywords: main beam, carrying capacity, reinforcement, external reinforcement, free rod, staging of work, relative deformation, deflection.


2014 ◽  
Vol 6 (4) ◽  
pp. 197-225 ◽  
Author(s):  
Eliana Carranza

Differences in relative female employment by soil texture are used to explain the heterogeneous deficit of female children across districts within India. Soil texture varies exogenously and determines the depth of land tillage. Deep tillage, possible in loamy but not in clayey soil textures, reduces the demand for labor in agricultural tasks traditionally performed by women. Girls have a lower economic value where female labor opportunities are fewer. Consistently, higher relative female employment in agriculture improves the ratio of female to male children in districts that have a smaller fraction of loamy relative to clayey soils. (JEL J16, J23, J43, O13)


Author(s):  
Sadanand Kulkarni ◽  
Soumendu Jana

High-speed rotating system development has drawn considerable attention of the researchers, in the recent past. Foil bearings are one of the major contenders for such applications, particularly for high speed and low load rotating systems. In foil bearings, process fluid or air is used as the working medium and no additional lubricant is required. It is known from the published literature that the load capacity of foil bearings depend on the operating speed, viscosity of the medium, clearance, and stiffness of the foil apart from the geometric dimensions of the bearing. In case of foil bearing with given dimensions, clearance governs the magnitude of pressure developed, whereas stiffness dictates the change in radial clearance under the generated pressure. This article deals with the effect of stiffness, clearance, and its interaction on the bump foil bearings load-carrying capacity. For this study, four sets of foil bearings of the same geometry with two levels of stiffness and clearance values are fabricated. Experiments are carried out following two factor-two level factorial design approach under constant load and in each case, the lift-off speed is measured. The experimental output is analyzed using statistical techniques to evaluate the influence of parameters under consideration. The results indicate that clearance has the maximum influence on the lift-off speed/ load-carrying capacity, followed by interaction effect and stiffness. A regression model is developed based on the experimental values and model is validated using error analysis technique.


2020 ◽  
Vol 313 ◽  
pp. 00031
Author(s):  
Glib Vatulia ◽  
Maryna Rezunenko ◽  
Dmytro Petrenko ◽  
Yevhen Balaka ◽  
Yevhen Orel

The article deals with the integrated approach to the study of the behaviour of rectangular CFST columns under eccentric compression. Such an approach includes the development of methods for assessing the magnitude of the carrying capacity, assessing the degree of reliability and credibility of the obtained results, as well as studying the nature of the development of columns deformations at various stages of loading. The authors developed a mathematical model for calculation of columns carrying capacity under eccentric compression based on statistical methods. Substantial amount of experimental data collected by the world leading laboratories enabled obtaining a regression dependence of the columns carrying capacity that takes into account the impact of the physical and geometric characteristics of such structures. High degree of model confidence is confirmed by a comparative analysis with experimental results that are not involved in the development of the model, as well as with calculations performed according to Eurocode, Japanese and Chinese regulatory documents. The article presents experimental studies of the nature of deformations development on the surface of the steel shell and inside the concrete core of various lengths rectangular columns. As a result of the experimental tests, it was established that the longitudinal strains of the compressed area of the shell have the most significant impact on the bearing capacity of eccentrically compressed steel concrete samples.


Author(s):  
Ravindra Mallya ◽  
Satish B Shenoy ◽  
Raghuvir Pai

The static characteristics of misaligned three-axial water-lubricated journal bearing in the turbulent regime are analyzed for groove angles 36° and 18°. Ng and Pan’s turbulence model is applied to study the turbulence effects in the journal bearing. The static parameters such as load-carrying capacity, friction coefficient, and side leakage are found for different degree of misalignment (DM). The change in flow regime of the lubricant from laminar to turbulent and the increase in misalignment, improved the load capacity of the bearing. For lightly loaded bearings, the friction coefficient of the bearing increased with the increase in Reynolds number.


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