Experimental Arrangements for Investigation of Soil Stresses Developed Around a Displacement Pile : The Use of Miniature Soil Stress Measuring Cells in Laboratory Applications Involving Stress Reversals

To address a recent challenge related to broken spikes in premium elastic fastening systems that have led to at least ten derailments and require manual walking inspections as well as build upon mechanistic-empirical (M-E) design principles for future fastening system component design, this paper quantifies the vertical, lateral, and longitudinal fastening system loads under revenue service traffic in a curve that has regularly experienced spike fastener fatigue failures. Previous data has indicated that the high rail of Track 3 experienced the most failures at this location. The data from this investigation sheds light into why failures are more predominant at this location than others and how the vertical, lateral, and longitudinal loads cannot be considered independently. Specifically, while the magnitude of the applied loading was the lowest on the high rail of Track 3, the threshold for failure was also the lowest given the operations at this location led to unloading of the high rail, thus indirectly highlighting the importance of friction within a fastening system. The data also show the high rail of Track 3 was subjected to the highest L/V load ratios and was an outlier in the typical lateral load reversals applied likely leading to spike stress reversals and thus a shorter fatigue life. Finally, based upon the data, it is recommended that to mitigate spike failures, as well as similar fastener challenges in other track types (e.g. rail seat deterioration, etc.) railroads should ensure trains operate close to the balance speed and use fastening system that transfer loads through friction. This study also provides novel data for M-E design of fastening systems.

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Stress measuring and monitoring for main tower of Guangzhou Pearl River HuangPu Bridge

10.1117/12.839306 ◽

2008 ◽

Author(s):

Wei-feng Wang ◽

Jian-dong Liang

Keyword(s):

Pearl River ◽

Stress Measuring

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The Mechanical Properties Comparative Analysis for Socked and Non-Socketed Composite Pile

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.748 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 748-750

Author(s):

Heng Chen ◽

Ke Sheng Ma

Keyword(s):

Mechanical Properties ◽

Comparative Analysis ◽

Seismic Performance ◽

Dynamic Loads ◽

Vertical Load ◽

Interlayer Thickness ◽

Static Loads ◽

Soil Stress ◽

Composite Pile ◽

Static And Dynamic Loads

For socked and non-socketed piles in the different mechanical behavior under static and dynamic loads, the paper use ABAQUS to model, simulate the pile , the soil interlayer thickness between the bottom of the pile and bedrock are 2m, 4m under vertical load and Earthquake, cushion cap, pile and pile soil stress situation found non-socketed piles when the soil interlayer thickness within a certain range, the composite pile small subside under dynamic, static loads, the non-socketed piles can better take advantage of the pile soil has a good seismic performance in the earthquake.

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Numerical Simulation of Pile-Bucket Foundation under Horizontal Load

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.460.169 ◽

2012 ◽

Vol 460 ◽

pp. 169-174

Author(s):

Wen Bai Liu ◽

Liang Yang ◽

Chen Xia Zhu

Keyword(s):

Failure Surface ◽

Horizontal Load ◽

Soil Pressure ◽

Passive Region ◽

Deep Soil ◽

Maximum Displacement ◽

Bucket Foundation ◽

Load Line ◽

Soil Stress ◽

Pressure Changes

The pile-bucket foundation is a new kind of foundation. In this paper, the ABAQUS software was used to analyze the soil displacement field and the soil stress field surrounding of the pile-bucket foundation under the multi-cycle horizontal loading. Under the horizontal load, the active area of soil separated from the basics; the passive region takes the shape of a parabolic ring of soil wedge rotate failure surface. The maximum displacement was in the direction of horizontal load line on the surface of soil near the bucket. Horizontal and vertical soil pressure changes are concentrated under the surface of the soil near the bucket, and the maximum horizontal soil stress was in the deep soil around the bucket. There is a point of inflection between 1/3 and 1/2 of the pile into soil , and the soil pressure that upper and lower the point increased in the opposite direction. The horizontal forced resistance of the foundation mainly distributed under the bucket and 1/2 of the pile into soil .The conclusion could provide a reference basis for the analysis of bearing mechanism and destruction characters of pile-bucket foundation

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Genetic Analysis of Half Diallel Matting with Different Methods and their Comparisons for Yield and its Associated Traits in Sunflower under Saline Soil Stress Conditions

Helia ◽

10.1515/helia-2017-0001 ◽

2017 ◽

Vol 40 (66) ◽

Cited By ~ 1

Author(s):

Mohamed Ali Abd El-Satar

Keyword(s):

Genetic Analysis ◽

Agricultural Research ◽

Saline Soil ◽

Block Design ◽

Diallel Cross ◽

Head Diameter ◽

Physiological Maturity ◽

Randomized Complete Block Design ◽

Soil Stress ◽

Half Diallel

AbstractA half diallel cross between five divergent sunflower genotypes was evaluated under two contrast locations of Kafr El-Hamam (fovourable soil as a control) and Tag Al-Ezz (as salt affected soil) Agricultural Research Stations using randomized complete block design with three replications. High significance variation among genotypes and their components was detected for all studied traits at both and combined locations. Selection in early generations would be effective at both locations for improving days to 50 % flowering, days to physiological maturity, plant height, head diameter, No. of green leaves plant

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