scholarly journals Impacts of Soil Contamination on the Response of Piles Foundation under a Combination of Loading

2016 ◽  
Vol 6 (1) ◽  
pp. 917-922 ◽  
Author(s):  
M. O. Karkush
Keyword(s):  
Bearing Capacity ◽  
Industrial Wastewater ◽  
Clayey Soil ◽  
Lateral Displacement ◽  
Axial Loading ◽  
Vertical Displacement ◽  
Soil Samples ◽  
Laboratory Model ◽  
Cross Sectional ◽  
Thermal Electric Power Plant

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.

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
Keyword(s):  
Carrying Capacity ◽  
Industrial Wastewater ◽  
Clayey Soil ◽  
Load Capacity ◽  
Soil Samples ◽  
Single Pile ◽  
Clayey Soils ◽  
Cyclical Loading ◽  
Group 2 ◽  
Heavy Loads

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.

scholarly journals Geotechnical Evaluation of Clayey Soil Contaminated with Industrial Wastewater

2017 ◽  
Vol 63 (1) ◽  
pp. 47-62 ◽  
Author(s):  
M. O. Karkush ◽  
T. A. A. Al-Taher
Keyword(s):  
Moisture Content ◽  
Industrial Wastewater ◽  
Clayey Soil ◽  
Soil Samples ◽  
Geotechnical Properties ◽  
Oil Refinery ◽  
Unit Weight ◽  
Initial Void Ratio ◽  
Field Unit ◽  
Contaminated Area

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.

Correlation of axial loaded magnetic resonance imaging with clinical symptoms in lumbar spinal canal stenosis patients

MedPharmRes ◽  
2019 ◽  
Vol 2 (4) ◽  
pp. 15-19
Author(s):  
Son Nguyen ◽  
Son Vi ◽  
Hoat Luu ◽  
Toan Do
Keyword(s):  
Spinal Canal ◽  
Clinical Symptoms ◽  
Axial Loading ◽  
Spinal Canal Stenosis ◽  
Leg Pain ◽  
Cross Sectional ◽  
Canal Stenosis ◽  
Conventional Mri ◽  
Frame System ◽  
Lumbar Spinal

There are cases when symptoms are available but no abnormal stenosis is found in MRI and vice versa. Axial-loaded MRI has been shown that it can demonstrate more accurately the real status of spinal canal stenosis than conventional MRI. This is the first time we applied a new system that we have recreated from the original loading frame system in order to fit with the demands of Vietnamese people. Sixty-two patients were selected from Phu Tho Hospital in Phu Tho Province, Vietnam, who fulfilled the inclusion criteria. The Anterior-posterior diameter (APD), Dura Cross-sectional Area (DSCA) in conventional MRI and axial loaded MRI, and changes in APD and DCSA were determined at the single most constricted intervertebral level. The APD and DCSA in axial loaded MRI had very good significant correlations with VAS for back pain (rs=0.83, 0.79), leg pain (rs=0.69, 0.57) and JOA score (rs=0.70, 0.65). APD and DCSA in axial loaded MRI significantly correlated with the severity of symptoms. Our axial loading MRI provides more valuable information than the conventional MRI for assessing patients with LSCS.

Load-Bearing Capacity of Direct Inlay-Retained Fibre-reinforced Composite Fixed Partial Dentures with Different Cross-Sectional Pontic Design

2017 ◽  
Vol 68 (1) ◽  
pp. 94-100
Author(s):  
Oana Tanculescu ◽  
Adrian Doloca ◽  
Raluca Maria Vieriu ◽  
Florentina Mocanu ◽  
Gabriela Ifteni ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Fracture Pattern ◽  
Load Bearing Capacity ◽  
Cross Sectional ◽  
Load Bearing ◽  
Reinforced Composite ◽  
Polyethylene Fibre

The load-bearing capacity and fracture pattern of direct inlay-retained FRC FDPs with two different cross-sectional designs of the ponticwere tested. The aim of the study was to evaluate a new fibre disposition. Two types of composites, Filtek Bulk Fill Posterior Restorative and Filtek Z250 (3M/ESPE, St. Paul, MN, USA), and one braided polyethylene fibre, Construct (Kerr, USA) were used. The results of the study suggested that the new tested disposition of the fibres prevented in some extend the delamination of the composite on buccal and facial sides of the pontic and increased the load-bearing capacity of the bridges.

scholarly journals An Integrated Study of Toxocara Infection in Honduran Children: Human Seroepidemiology and Environmental Contamination in a Coastal Community

2020 ◽  
Vol 5 (3) ◽  
pp. 135 ◽  
Author(s):  
Sergio A. Hernández ◽  
José A. Gabrie ◽  
Carol Anahelka Rodríguez ◽  
Gabriela Matamoros ◽  
María Mercedes Rueda ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Soil Samples ◽  
Environmental Study ◽  
Enzyme Linked Immunosorbent Assay ◽  
Student Body ◽  
Nested Polymerase Chain Reaction ◽  
Serological Tests ◽  
Cross Sectional ◽  
Coastal Community ◽  
Pcr Rflp

(1) Background: Infections caused by Toxocara canis and T. cati are considered zoonoses of global importance. Reports from North and South America indicate that human infections are widespread in both continents, but epidemiological information from Central America is still lacking. (2) Methodology: In the present cross-sectional multi-year study, we aimed to undertake the first seroepidemiological and environmental study on toxocariasis in Honduras. This included the determination of seroprevalence of anti-Toxocara spp. antibodies in children using a Toxocara spp. purified excretory-secretory antigens enzyme-linked immunosorbent assay (TES-ELISA) and a confirmatory Western blot. As well, through statistical analysis including logistic regression we aimed at identifying relevant biological and epidemiological factors associated with seropositivity. The study also entailed detection of parasites’ eggs in the soil samples both through Sheather’s concentration method and a nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. (3) Results: The study was undertaken in a coastal community of Honduras in 2 different years, 2015 and 2017. A total of 88 healthy schoolchildren completed the study, with participation of 79% (73/92) and 65% (46/71) of the student body in 2015 and 2017, respectively. Thirty-one children participated in both years (i.e., dual participants). Through both serological tests, seropositivity was confirmed in 88.6% (78/88) of children. Due to the high number of seropositives, logistic regression analysis was not possible for most socio-economic and epidemiological variables. Eosinophilia, on the other hand, was associated with seropositivity, independently of other intestinal helminthic infections. Continued seropositivity was observed in most of the dual participants, while seroconversion was determined in 8 of these children. Microscopic examination of soil samples did not yield any positive results. Through nested PCR-RFLP, 3 of the 50 samples (6%) were positive for Toxocara spp.; two were identified as T. canis and one as T. cati. (4) Conclusions: This work documents for the first time, high levels of human exposure to Toxocara spp. in Honduras. These findings, along with the country’s favorable epidemiological conditions for this zoonosis, emphasize the need for more research to determine whether this infection is underreported in the country.

scholarly journals Experimental study on dynamic response of model shield tunnel induced by moving-axle loads of subway train

2018 ◽  
Vol 14 (10) ◽  
pp. 155014771880278
Author(s):  
Mengxi Zhang ◽  
Xiaoqing Zhang ◽  
Lei Li ◽  
Chengyu Hong
Keyword(s):  
Time History ◽  
Vertical Displacement ◽  
Wheel Speed ◽  
Dynamic Responses ◽  
Scale Model ◽  
Shield Tunnel ◽  
Laboratory Model ◽  
Cover Depth ◽  
Axle Loads ◽  
Subway Train

A new testing method was introduced to apply moving-axle loads of a subway train on a track structure. In order to investigate the dynamic responses of the shield tunnel subjected to moving-axle loads, a series of laboratory model tests were conducted in a 1/40 scale model tunnel. The influences of the axle load, the wheel speed, and the cover depth of the shield tunnel on the vertical displacement and acceleration of the lining were presented and discussed. Parametric studies revealed that the vertical displacement–time history of the lining presents a “W” shape due to the combined action of two axles of a bogie. The peak value of the vertical displacement increased with the axle load linearly, while it decreased with the increase in the cover depth. Moreover, response time of the displacement decreased with the increase in the wheel speed, but the peak values remained stable at the same level. Finally, a three-dimensional dynamic finite element model was adopted to simulate the movement of the axle loads and calculate the responses of the lining. The numerical results analysis agrees well with experimental results.

scholarly journals The Gujarat, West India, earthquake (Jan 26th 2001). A geodynamic event in an intraplate compressional regime?

2001 ◽  
Vol 34 (4) ◽  
pp. 1405
Author(s):  
Γ. Δ. ΔΑΝΑΜΟΣ ◽  
Ε. Λ. ΛΕΚΚΑΣ ◽  
Σ. Γ. ΛΟΖΙΟΣ
Keyword(s):  
Large Scale ◽  
Lateral Displacement ◽  
Indian Subcontinent ◽  
Plate Boundary ◽  
Horizontal Displacement ◽  
Vertical Displacement ◽  
Lateral Spreading ◽  
Tectonic Deformation ◽  
Epicentral Area ◽  
Surface Ruptures

The Jan. 26, 2001, Ms=7.7 earthquake occurred in Gujarat region of W. India, which lies 200-400 Km away from the active plate boundary zone, between the Indian subcontinent and the Asian plate, along the India-Pakistan border and the Himalayan belt. An Ms=7.7±0.2 earthquake also occurred in the same region in 1819. A zone of co-seismic E-W surface ruptures, 30-40 Km long and 15-20 Km wide, observed near the epicentral area and seems to be associated with pre-existing reverse faults and thrust folds, which were partially reactivated during the recent earthquake. Except the reverse vertical displacement a significant right lateral displacement was also observed along these E-W surface ruptures. This Ms=7.7 seismic event has been also accompanied by a large scale flexural-slip folding, as the absence of significant co-seismic fault displacement and fault scarp shows. This type of compressional tectonic deformation is also confirmed by the focal mechanism of the earthquake and the seismo-tectonic "history" of the area. The NW-SE open cracks, also observed along the same zone, are associated with the right lateral horizontal displacement of the reactivated fault (or branch faults) and the development of local extensional stress field in the huge anticlinic hinges of the co-seismic flexural-slip folds. A large number of ground ruptures, failures and open cracks are also associated with extensive sand boils, liquefaction phenomena and lateral spreading.

scholarly journals Pavement Subgrade Stabilization with Lime and Cellular Confinement System

2018 ◽  
Vol 13 (2) ◽  
pp. 87-93
Author(s):  
Muhammet Vefa Akpinar ◽  
Erhan Burak Pancar ◽  
Eren Şengül ◽  
Hakan Aslan
Keyword(s):  
Bearing Capacity ◽  
Large Scale ◽  
Clayey Soil ◽  
Dry Weight ◽  
Hydrated Lime ◽  
Load Test ◽  
Lime Stabilization ◽  
Plate Load Test ◽  
Reaction Coefficient ◽  
Geocell Reinforcement

In this study effectiveness of lime stabilization and geocell reinforcement techniques of roads was investigated for low bearing capacity subgrades. For this purpose, a large-scale plate load test was designed and used. Clayey soil with high moisture content was reinforced with different percentages of hydrated lime (5%, 10%, 15% dry weight of the soil). The deflection and stress results indicated that lime stabilization or geocell reinforcement alone did not significantly increase subgrade reaction coefficient and bearing capacity values. Promising results were obtained on stabilization of weak subgrade when both techniques were used together. It was determined that cellular reinforcement increased the reaction modulus coefficient value and bearing capacity of the subgrade soil by more than 15% compared to the lime stabilization.

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