Research and Application of Stress and Strain Testing Method for Plain Concrete Pile

At present, the stress-strain test of pile body mainly focuses on precast pile and cast-in-place pile with reinforcement, and this is mainly because the pre-assembly of test components can be carried out in the pile body or reinforcement cage before the prefabricated pile is formed. When the pile is formed, it could be embedded together with the pile body or reinforcement cage. But for the cast-in-place plain concrete pile field test research report is rare. In view of the shortcomings of the existing test methods in the test of plain concrete piles, the resistance strain gauge and inclinometer are improved to realize their application in the field test of plain concrete piles, which is employed for the deformation characteristics test of plain concrete pile under horizontal load. The test results show the applicability of the improved test method, which provides useful references for similar research.

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Field Test Study on Cutting Obstacle Piles Directly by Shield Cutters

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.1433 ◽

2013 ◽

Vol 353-356 ◽

pp. 1433-1439

Author(s):

Fei Wang ◽

Da Jun Yuan ◽

Rong Cai ◽

Yong Jiang Mu ◽

Meng Shu Wang

Keyword(s):

Reinforced Concrete ◽

Field Test ◽

Social Benefits ◽

Test Results ◽

Concrete Piles ◽

Test Study ◽

Concrete Pile ◽

Reinforced Concrete Piles ◽

Cutting Effect ◽

Configuration Scheme

Shield cutting obstacle pile directly has significant economic and social benefits compared to traditional methods, however, the corresponding cutting technology is far from mature currently in the international. Based on the construction need of cutting 14 bridge piles with the diameter of 1.0~1.2 meters by Suzhou subway shield, the preliminary scheme of cutter configuration was studied and proposed first, and then the worlds first field test of shield cutting reinforced concrete piles was carried out, the effect and rule of shield cutters cutting piles were analyzed, and the cutter configuration scheme was verified and optimized. The test results indicate that the shell cutter is fit for cutting reinforced concrete pile, its cutting effect on rebar and concrete is shear cutting; In order to make rebar shorter, we should make the rebar be cut off instead of pulled off as possible as we can. The main damage form of shell cutter is alloy cracked. Cutting side pile produces more damage on shell cutter than cutting central pile. The shell cutter configuration scheme should not only satisfy the whole cutting ability and covering the entire cutting plane, but also to be favorable to fix rebar by surrounding concrete.

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Analisa Pengujian Repeatability Timbangan Elektronik dengan Metode Syarat Teknis Timbangan Non Otomatis dan Metode NMI Australia

Elinvo (Electronics Informatics and Vocational Education) ◽

10.21831/elinvo.v4i2.28356 ◽

2019 ◽

Vol 4 (2) ◽

pp. 176-183

Author(s):

Ponco Wali

Keyword(s):

Research Method ◽

Test Methods ◽

Test Results ◽

Repeat Testing ◽

Testing Method ◽

Technical Requirements

Testing repeat electronic scales with non-automatic scales technical requirements so far is fairly long if not using a calculator or computer. The aim of this research is to compare the repeatability testing method of electronic scales using methods according to the technical requirements of non-automatic scales and the Australian NMI method, both of which refer to OIML R76 in determining the validity or cancellation of electronic scales repeatability testing. This research method is done through repeat testing on 3 samples of electronic scales, then on each electronic scale 2 test methods are performed. The conclusion is that the electronic scales repeatability testing uses the non-automatic scales technical requirements method and the Australian NMI method has some differences although both refer to OIML R76. These differences include several points, namely the charge used, the method of adding additions, the formula for determining electronic scales, and different test results. The Australian NMI method is deemed to make it easier and more time efficient compared to the non-automatic weighing technical requirements method.

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The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction

Prosthetics and Orthotics International ◽

10.1177/0309364614527121 ◽

2014 ◽

Vol 39 (3) ◽

pp. 232-237 ◽

Cited By ~ 10

Author(s):

Bryce Dyer

Keyword(s):

Field Test ◽

Aerodynamic Drag ◽

Field Tests ◽

Field Testing ◽

Test Method ◽

Limb Amputation ◽

Small Scale ◽

Prosthetic Limb ◽

Testing Method ◽

Competitive Cyclists

Background/Objectives: This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. Study design: The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. Methods: An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. Results: With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. Conclusion: A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Clinical relevance Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders’ equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible.

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Experimental Research on Vibration Characteristics of Laminated Composite Cantilever Beam

10.1115/omae2021-63227 ◽

2021 ◽

Author(s):

Rui Yang ◽

Xiaobin Li ◽

Hongxi Li

Keyword(s):

Cantilever Beam ◽

Optical Measurement ◽

Laminated Composite ◽

Experimental Methods ◽

Test Methods ◽

Vibration Characteristics ◽

Test Method ◽

Vibration Measurement ◽

Vibration Test ◽

Test Results

Abstract In this paper, the vibration characteristics of laminated composite cantilever beam is taken as the research object. Firstly, a vibration formula specific for laminated composite cantilever beam is derived, from which the low order natural frequency of laminated composite cantilever beam is calculated; Secondly, two experimental methods, electrical and optical measurement, are used to study the vibration characteristics of laminated composite cantilever beam, and the influence of different test methods, sensor types, number of measuring points and excitation methods on the test results are analyzed. Through the combination of theory and experiment, a test method that can be applied to the vibration test of composite material laminated structure cantilever beam is obtained. Based on the laser vibration measurement method in the optical method, the results show that the deviation between the experimental data and the theoretical solution is the smallest when the distance between the probe and the specimen is 0.5m and the sampling time is 5s by using the optical fiber vibrometer. The research content of this article can provide a reasonable reference for related vibration test research.

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Seismic behaviour of prestressed high-strength concrete piles under combined axial compression and cyclic horizontal loads

Advances in Structural Engineering ◽

10.1177/1369433218806191 ◽

2018 ◽

Vol 22 (5) ◽

pp. 1089-1105 ◽

Cited By ~ 2

Author(s):

Xizhi Zhang ◽

Sixin Niu ◽

Jia-Bao Yan ◽

Shaohua Zhang

Keyword(s):

Finite Element ◽

Axial Compression ◽

High Strength Concrete ◽

High Strength ◽

Element Model ◽

Test Results ◽

Seismic Behaviour ◽

Strength Concrete ◽

Concrete Piles ◽

Concrete Pile

In order to simulate the seismic behaviour of the prestressed high-strength concrete piles under working state, six full-scale prestressed high-strength concrete piles were tested under combined axial compression and cyclic horizontal loads. Different axial compression levels and prestressing levels of prestressed tendons were studied in this test programme. The failure mode, bending resistance, displacement ductility, stiffness degradation and energy dissipation of the prestressed high-strength concrete piles under different loading scenarios were measured and analysed. Test results indicated that the axial compression ratio and prestressing level of prestressed tendon significantly influenced the seismic performance of prestressed high-strength concrete piles. Theoretical models were developed to predict cracking, yielding and ultimate bending resistances of the prestressed high-strength concrete pile under combined compression and bending. Finite element model was also developed to simulate the ultimate strength behaviour of the prestressed high-strength concrete pile under combined compression and flexural bending. The accuracies of the theoretical and finite element model were checked through validations of their predictions against the reported test results.

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Methods to Evaluate Cleaners and Sanitizers

Journal of Food Protection ◽

10.4315/0362-028x-45.13.1257 ◽

1982 ◽

Vol 45 (13) ◽

pp. 1257-1260 ◽

Cited By ~ 4

Author(s):

DALE L. SCHEUSNER

Keyword(s):

Test Methods ◽

Test Method ◽

Test Results ◽

Standard Laboratory ◽

Test Procedures ◽

Laboratory Methods ◽

Product Use ◽

Cellulose Sponge ◽

Equivalent Test ◽

Recovery Methods

Methods to evaluate germicides can be grouped into three categories: standard laboratory tests, in-use tests and simulated-use tests. Standard laboratory methods, such as the Available Chlorine Germicidal Equivalent test, are specifically defined for reproducibility in any laboratory by any operator, but the test results often lack relevance to actual product-use conditions. In-use test methods are relevant to product-use; however, in-use test procedures do not permit proper controls to be included in the organism recovery methods. Contact plates give an estimate of organism numbers which is only 25% of the theoretical number of organisms present. Organism recovery using a swab, cellulose sponge or tube sampler give estimates of organisms ranging from 91 to 111% of theoretical. The tube sampler is a 1-in. length of flexible tubing having a 1-in. interior diameter and a smooth end, which can make a water-tight seal on a flat surface. Simulated use testing yields data which are relevant to actual product-use. A cafeteria tray is soiled, inoculated and cleaned in a manner to simulate actual product-use. This test method permits the necessary controls to be used. Tray-test reproducibility is as good as that of the other recovery methods tested and organism recovery is quantitative. The tray test provides a means for determining biological cleaning where the effect of both cleaning and germicidal activity are measured together.

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Field Test Method for Residual Stress in Plain Concrete Pavements and Structures

Journal of Testing and Evaluation ◽

10.1520/jte20130108 ◽

2014 ◽

Vol 42 (3) ◽

pp. 20130108 ◽

Cited By ~ 1

Author(s):

Daniel I. Castaneda ◽

Jacob D. Henschen ◽

David A. Lange

Keyword(s):

Residual Stress ◽

Field Test ◽

Plain Concrete ◽

Test Method ◽

Concrete Pavements ◽

Field Test Method

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Performance characteristics of polymerase chain reaction and histological methods for the detection of Haplosporidium nelsoni in the eastern oyster (Crassostrea virginica)

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638715592666 ◽

2015 ◽

Vol 27 (4) ◽

pp. 476-488 ◽

Cited By ~ 2

Author(s):

Nellie Gagné ◽

Anne Veniot ◽

Mary Stephenson ◽

Carol McClure

Keyword(s):

Polymerase Chain Reaction ◽

Test Methods ◽

Test Method ◽

Performance Characteristics ◽

Analytical Sensitivity ◽

Test Results ◽

Fitness For Purpose ◽

Chain Reaction ◽

Repeatability And Reproducibility ◽

Polymerase Chain

Fitness for purpose and validation are increasingly becoming a benchmark in the development of test methods for the diagnosis of infectious diseases in aquatic animals. The design of the evaluation and the analysis of data are critical to demonstrate test method performance characteristics and fitness for purpose, as stated in the World Organization for Animal Health pathway for test validation. Three test methods for the detection of the oyster parasite Haplosporidium nelsoni were selected for the validation study described herein: histology, end-point polymerase chain reaction (PCR), and real-time PCR (qPCR). Preliminary work evaluated the analytical sensitivity and specificity of the PCR and qPCR assay in development. The following stage used test results on 100 oysters in 3 different laboratories to assess diagnostic sensitivity (DSe), diagnostic specificity (DSp), repeatability, and reproducibility. Repeatability and reproducibility were within 68–95%. The final part of the project evaluated DSe and DSp using test results on 400 oysters and results from the first 100 oysters tested. In the absence of a 100% gold standard test, latent class modeling methods were explored to characterize the tests (i.e., Bayesian analyses). For both PCR methods, DSe was >90%, and in the 60% range for histology, whereas DSp was >90% for all methods. Based on the results of this validation, a threshold cycle value of 30 for qPCR corresponds to the limit of sensitivity for histology where unreliable detection becomes more frequent, thus providing a threshold helpful in diagnostic settings where both histology and qPCR are used.

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The Research of Negative Ion Test Method for Fabric

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.138 ◽

2013 ◽

Vol 756-759 ◽

pp. 138-140 ◽

Cited By ~ 1

Author(s):

Yun Sen Sun ◽

Bo Qiu ◽

Qing Shan Li

Keyword(s):

Influence Factors ◽

Test Methods ◽

Test Method ◽

Ion Concentration ◽

Negative Ion ◽

Testing Device ◽

Test Results ◽

Influence Of Temperature ◽

Functional Textiles ◽

Temperature And Humidity

We developed a device for automatic closed friction and analyzed its test results in this paper, which showed the influence factors in the test methods of textile negative ion occurrence amounts. The textile negative ion occurrence amounts in different time stages were tested in this process; the analysis of its influence of temperature and humidity has certain reference significance for improving testing device for testing textile negative ion concentration, on the basis, functional textiles were also studied. Finally, we put forward the influence factors in the test methods of textile negative ion occurrence amounts.

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