Laboratory tests of buried plastic pipes in sand under repeated load

2017 ◽  
pp. 517-522
Author(s):  
S.N. Moghaddas Tafreshi ◽  
O. Khalaj ◽  
J. Khanmohammadi
Keyword(s):  
Laboratory Tests ◽  
Plastic Pipes ◽  
Repeated Load

scholarly journals Use of slag (with cement) for improving the performance of expansive soil of road pavement subgrade

2019 ◽  
Vol 276 ◽  
pp. 05002
Author(s):  
Agus Ika Putra ◽  
Mohamed A. Shahin
Keyword(s):  
Unconfined Compressive Strength ◽  
Laboratory Tests ◽  
Expansive Soil ◽  
Curing Time ◽  
Road Pavement ◽  
Subgrade Soil ◽  
Stabilized Soil ◽  
Repeated Load ◽  
Repeated Load Triaxial ◽  
Selection Of

The study presented in this paper evaluates the suitability of using slag (with cement) as a stabilizer, for improving the performance of expansive subgrade soil in road pavement. Several laboratory tests were conducted to determine the geotechnical engineering characteristics of the expansive soil and associated mechanical engineering performance. The tests conducted include the particle size distribution, standard Proctor compaction, Atterberg’s limits, free swelling, permeability, California bearing ratio (CBR), unconfined compressive strength (UCS), and repeated load triaxial (RLT). In this study, the use of slag (with cement) as a stabilizer followed three proportion schemes, and the selection of a specific stabilizer proportion was determined based on UCS value that satisfies the required standard as a subgrade for road pavement. The results recommended a stabilizer proportion for the soil studied to be 13.5% slag + 1.5% cement at 28 days curing time. This mixture resulted in a remarkable increase in the UCS value of eight times higher than the UCS value of the non-stabilized soil. The CBR value of the mixture was four times higher than the minimum required value for design of road pavement. The study presented herein confirmed that the exploitation of the by-product material of slag can indeed be useful, both in terms of improving the performance of the subgrade soil for road pavement and sparing the environment a spread of significant potential pollutant.

Structural Behavior of Buried Plastic Pipe

1974 ◽  
Vol 1 (2) ◽  
pp. 199-207 ◽  
Author(s):  
A. Y. Fagnou ◽  
Karim W. Nasser
Keyword(s):  
External Load ◽  
Laboratory Tests ◽  
Structural Behavior ◽  
Bending Moments ◽  
Vertical Deflection ◽  
Inside Diameter ◽  
Plastic Pipe ◽  
Plastic Pipes ◽  
Loose Soil

This investigation is a study of some of the factors which affect the ability of a plastic pipe to support earth loads. Some of the factors that were considered are the strength of the pipe and the soil conditions.Two series of laboratory tests, using two soil densities, were conducted on two types of plastic pipes that had six wall thicknesses. Deflection gauges were used to measure changes in the inside diameter due to an external load that was applied on the buried specimens.The results indicated that loose soil fill will produce about 70% more vertical deflection in a pipe than dense soil fill. Also, it was observed that vertical deflections can best be assessed by considering the resistence of the pipe to membrane forces rather than bending moments as stipulated in the A.S.T.M. Specifications.

Analysis of Repeated-Load Field Testing of Buried Plastic Pipes

2000 ◽  
Vol 126 (3) ◽  
pp. 271-277 ◽  
Author(s):  
Edward Faragher ◽  
Paul R. Fleming ◽  
Christopher D. F. Rogers
Keyword(s):  
Field Testing ◽  
Plastic Pipes ◽  
Repeated Load

Critical limb ischaemia in diabetes: definition, assessment, prognosis

VASA ◽  
2001 ◽  
Vol 30 (Supplement 58) ◽  
pp. 21-27
Author(s):  
Luther
Keyword(s):  
Diabetic Foot ◽  
Laboratory Tests ◽  
Critical Limb Ischaemia ◽  
Limb Ischaemia ◽  
Clinical Use ◽  
Arterial Reconstruction ◽  
Arterial Circulation ◽  
Diabetic Foot Disease ◽  
Foot Disease ◽  
Fontaine Classification

In diabetic foot disease, critical limb ischaemia (CLI) cannot be precisely described using established definitions. For clinical use, the Fontaine classification complemented with any objective verification of a reduced arterial circulation is sufficient for decision making. For scientific purposes, objective measurement criteria should be reported. Assessment of CLI should rely on the physical examination of the limb arteries, complemented by laboratory tests like the shape of the PVR curve at ankle or toe levels, and arteriography. The prognosis of CLI in diabetic foot disease depends on the success of arterial reconstruction. The best prognosis for the patients is with a preserved limb. Reconstructive surgery is the best choice for the majority of patients.

The Reliability of Retrieval-Induced Forgetting

2012 ◽  
Vol 17 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Rosalind Potts ◽  
Robin Law ◽  
John F. Golding ◽  
David Groome
Keyword(s):  
Individual Differences ◽  
Recognition Test ◽  
Laboratory Tests ◽  
The Other ◽  
Clinical Factors ◽  
Test Items ◽  
T1 And T2 ◽  
Test Materials ◽  
Induced Forgetting

Retrieval-induced forgetting (RIF) refers to the finding that the retrieval of an item from memory impairs the retrieval of related items. The extent to which this impairment is found in laboratory tests varies between individuals, and recent studies have reported an association between individual differences in the strength of the RIF effect and other cognitive and clinical factors. The present study investigated the reliability of these individual differences in the RIF effect. A RIF task was administered to the same individuals on two occasions (sessions T1 and T2), one week apart. For Experiments 1 and 2 the final retrieval test at each session made use of a category-cue procedure, whereas Experiment 3 employed category-plus-letter cues, and Experiment 4 used a recognition test. In Experiment 2 the same test items that were studied, practiced, and tested at T1 were also studied, practiced, and tested at T2, but for the remaining three experiments two different item sets were used at T1 and T2. A significant RIF effect was found in all four experiments. A significant correlation was found between RIF scores at T1 and T2 in Experiment 2, but for the other three experiments the correlations between RIF scores at T1 and T2 failed to reach significance. This study therefore failed to find clear evidence for reliable individual differences in RIF performance, except where the same test materials were used for both test sessions. These findings have important implications for studies involving individual differences in RIF performance.

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