CREATING A WORKING MODEL OF A DRIVERLESS  AIRFIELD TOW TRUCK

The purpose of the research in this paper is to develop a promising airfield driverless tow truck to increase the economic efficiency of aircraft towing facilities, including unmanned aircrafts as well as to ensure reliable operation in various climatic conditions. The research methods include the analysis of the experience of using such driverless airfield tow trucks abroad, the theory of calculating traction and speed indicators and experimental studies conducted during the creation and study of field tests of devices used to load the driving wheels of a tractor. To achieve the goal, the configuration of the structure being designed and its intended composition are determined analytically. The operation of the designed device in the traction mode is considered, and the characteristic of calculating its indicators when moving along the support surface is presented. The presented material briefly illustrates the process from creating a model of a driverless airfield tow truck to the created design of an existing sample, which will later be used to conduct its full-scale tests and a comprehensive assessment of its strength traction and speed characteristics.

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Computational and experimental studies of the strength of full-scale samples of pipes with defects "metal loss" and "dent with groove"

SCIENCE & TECHNOLOGIES OIL AND OIL PRODUCTS PIPELINE TRANSPORTATION ◽

10.28999/2541-9595-2020-10-3-226-233 ◽

2020 ◽

Vol 10 (3) ◽

pp. 226-233

Author(s):

Dmitry A. Neganov ◽

◽

Victor M. Varshitsky ◽

Andrey A. Belkin ◽

◽

...

Keyword(s):

Internal Pressure ◽

Experimental Studies ◽

Full Scale ◽

The Other ◽

Metal Loss ◽

Calculation Methods ◽

Reliable Operation ◽

Sufficient Stability ◽

Comparative Results ◽

The Moment

The article contains the comparative results of the experimental and calculated research of the strength of a pipeline with such defects as “metal loss” and “dent with groove”. Two coils with diameter of 820 mm and the thickness of 9 mm of 19G steel were used for full-scale pipe sample production. One of the coils was intentionally damaged by machining, which resulted in “metal loss” defect, the other one was dented (by press machine) and got groove mark (by chisel). The testing of pipe samples was performed by applying static internal pressure to the moment of collapse. The calculation of deterioration pressure was carried out with the use of national and foreign methodical approaches. The calculated values of collapsing pressure for the pipe with loss of metal mainly coincided with the calculation experiment results based on Russian method and ASME B31G. In case of pipe with dent and groove the calculated value of collapsing pressure demonstrated greater coincidence with Russian method and to a lesser extent with API 579/ASME FFS-1. In whole, all calculation methods demonstrate sufficient stability of results, which provides reliable operation of pipelines with defects.

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THE RULE OF COMBINING A PRIORI AND EXPERIMENTAL INFORMATION IN THE TASKS OF MANAGING TESTS OF COMPLEX TECHNICAL PRODUCTS ACCORDING TO THE BERNOULLI SCHEME

Vestnik komp iuternykh i informatsionnykh tekhnologii ◽

10.14489/vkit.2020.12.pp.003-013 ◽

2020 ◽

pp. 3-13

Author(s):

Yu. I. Buryak ◽

A. A. Skrynnikov

Keyword(s):

Field Experiments ◽

A Priori ◽

Field Tests ◽

Experimental Information ◽

Full Scale ◽

Testing Complex ◽

Series Of Experiments ◽

Full Scale Tests ◽

Technical Products

The article is devoted to the substantiation of the procedure for testing complex technical systems to assess the probability of performing the task, taking into account a priori data obtained from the results of modeling, field tests of components and prototypes, operation of analogues, etc. The conditions for the formation of a combined sample consisting of field experiments and experiments counted on the results of modeling are justified. Data uniformity is checked using the Student's criterion. The minimum volume of full-scale tests is determined by the requirement of equality of the amount of Fischer information about the estimated parameter obtained during full-scale tests and at the expense of a priori data A strategy for conducting field experiments is proposed, in which the required quality of evaluating the probability of completing the task is achieved with the minimum possible number of field experiments. At the first stage, a series of experiments with a volume equal to half of the required sample size is performed. At the second stage, the experiments are conducted sequentially with an assessment after each experiment of the requirements for the amount of information about the evaluated parameter and for the uniformity of data. Experiments are terminated when the specified requirements are met, and then a combined sample is formed, which is used to evaluate the probability of the system performing the task. A model example is considered. The estimation of the gain in the number of experiments performed at different probability values was carried out.

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Full-scale field tests on directly embedded steel pole foundations

Canadian Geotechnical Journal ◽

10.1139/t99-119 ◽

2000 ◽

Vol 37 (2) ◽

pp. 414-437 ◽

Cited By ~ 4

Author(s):

Asim Haldar ◽

VSN Prasad Yenumula ◽

T R Chari

Keyword(s):

Field Tests ◽

Ground Level ◽

Full Scale ◽

Design Parameters ◽

Embedment Depth ◽

Ultimate Capacity ◽

Backfill Material ◽

Different Types ◽

Full Scale Tests ◽

Laterally Loaded

The results of eight full-scale tests on directly embedded steel pole foundations are presented. Fully instrumented poles were tested to measure the various design parameters. Different types of backfills such as sand, in situ gravelly sand, crushed stone, and flowable material were used. Various parameters were measured, including applied moment, ground line deflection-rotation, rotation of the pole below the ground level, soil pressures, and bending moments in the poles. The behaviour of these foundations was explained through ultimate capacity and moment-rotation characteristics. Based on these test results, it was found that the capacity of the directly embedded pole foundation depends primarily on the compaction levels of backfill and the embedment length of the pole. Flowable backfill material, which does not require any compaction, was found to be most effective and promising. Even when the backfill was loose, the lateral capacity significantly increased by the addition of a baseplate or by installing the pole with an additional embedment depth. Various theories developed for laterally loaded rigid piles were used to predict the moment-rotation behaviour and the ultimate capacity of the directly embedded pole foundation with different types of backfill material. Results from the analytical investigations were compared with those obtained from the full-scale load tests. Comparisons show that the ultimate capacities predicted by the models ranged from 0.30 to 2.20 times the measured capacities.Key words: backfill, compaction, full-scale tests, laterally loaded rigid piles, transmission steel poles, ultimate moment.

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Experience in conducting field tests of metal structural constructions of coatings of the “BrSTU”

E3S Web of Conferences ◽

10.1051/e3sconf/202021202015 ◽

2020 ◽

Vol 212 ◽

pp. 02015

Author(s):

Mikalai Shalabyta ◽

Andrei Shuryn ◽

Tatsiana Shalabyta ◽

Viacheslav Dragan

Keyword(s):

Theoretical Calculations ◽

Field Tests ◽

Full Scale ◽

Complex Structures ◽

Building Structures ◽

The World ◽

Special Approach ◽

Full Scale Tests ◽

Degree Of Participation ◽

First Time

There are quite often statically complex structures, the reliability of theoretical calculations of which needs experimental verification in the world practice of design and construction. Studies of building structures functioning can be full-scale or carried out on their models in laboratory conditions depending on the goals set. Full-scale tests of building structures are more expensive, therefore, their implementation requires a special approach and justification. However, to check the operation of complex, critical structures which primarily include metal spatial large-span structures of coatings of buildings and structures especially those used for the first time to assess their bearing capacity, to establish the degree of participation in the construction of each of the elements, to study the operation of individual new nodal elements etc., only full-scale tests are required.

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Results of paint coating full-scale tests for coastal and ship structures in the tropical climate of Vietnam

Practice of Anticorrosive Protection ◽

10.31615/j.corros.prot.2021.99.1-2 ◽

2021 ◽

Vol 26 (1) ◽

Keyword(s):

Low Carbon Steel ◽

Field Tests ◽

Tropical Climate ◽

Full Scale ◽

Low Carbon ◽

Protective Efficiency ◽

Ship Structures ◽

Paint Coating ◽

Full Scale Tests ◽

Rubber Coatings

Full-scale tests are widely used to reliably evaluation the service life of paint and varnish coatings by assessing changes of their protective and decorative properties. Four-year exposure program was carried out in the tropical marine climate in South Vietnam (Dam Bay climate station of the Tre island, Nha Trang) of alkyd, chlorinated rubber coatings on low carbon steel, as well as epoxy coatings of various thicknesses with zinc-rich primer, urethane and acrylic outer layers. The tests were conducted on the base of the existing standards in the field of paints and varnishes intended for coastal and ship structures and were accompanied by the data collection and analysis of the meteorological factors for the classification of the area according to the degree of corrosiveness of the atmosphere. The change in the decorative properties of paint coating was assessed by visual and instrumental methods. The protective efficiency of the coatings was assessed by the time of occurrence of the first local defects or complete destruction of coating layers. According to the results of the conducted field tests, it was found that paint coating combinations correspond to expected lifetime in tropical climate from 2 to 5 years. A typical group suitable for a given climate is a two-component epoxy paint with an acrylic topcoat. A zinc-containing primer is recommended as an anticorrosive undercoat.

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Determination of the dynamic characteristics of the Colquitz River Bridge by full-scale testing

Canadian Journal of Civil Engineering ◽

10.1139/l96-058 ◽

1996 ◽

Vol 23 (2) ◽

pp. 536-548 ◽

Cited By ~ 21

Author(s):

C. E. Ventura ◽

A. J. Felber ◽

S. F. Stiemer

Keyword(s):

British Columbia ◽

Dynamic Characteristics ◽

Field Tests ◽

Free Vibrations ◽

Full Scale ◽

Ambient Vibration ◽

Mode Shapes ◽

Ambient Vibration Tests ◽

Vibration Tests ◽

Full Scale Tests

This paper presents the results of full-scale tests performed at the Colquitz River Bridge near Victoria, British Columbia (B.C.), Canada, during September 1992 to determine the dynamic characteristics of the structure. The five-span bridge was completed in 1954 and is part of the Trans-Canada Highway. It is 82.68 m long and 11.89 m wide, and has six continuous steel girders supporting a 175 mm thick concrete deck. This particular bridge was chosen for testing because of its typical nature of many B.C. bridges, its location in an area of high seismic risk, and its excellent site accessibility. The tests included extensive measurements of ambient vibrations induced by traffic and other sources to determine the dynamic characteristics of the bridge. The most significant vertical and lateral mode shapes and associated periods of vibration were determined from vibration measurements at more than 50 different locations of the deck, piers, and abutments. Although a large amount of data were collected, they were quickly processed and analyzed with an innovative system developed at The University of British Columbia. One of the important features of this system is that it permits the identification of the principal modes of vibration immediately after the data have been collected. In addition to the ambient vibration tests, quick release pullback tests were conducted to verify modal frequencies determined from the ambient vibration tests and to determine the damping of the fundamental modes. These tests consisted of loading the bridge at a selected location with a force of about 90 kN and then releasing this load very quickly to induce free vibrations. The information obtained from the field tests was used to refine a computer finite element model of the bridge, which, in turn, was used to gain insight into the dynamic behaviour of specific components of the bridge. Further, this information was used later by the bridge owner to evaluate the bridge's expected response during an earthquake. Key words: steel bridges, dynamic response, full-scale tests.

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A Collaborative Approach to Root Cause Analysis: With Reference to Suncor Energy Terra Nova Flexible Flowlines and Risers

Volume 5A: Pipeline and Riser Technology ◽

10.1115/omae2015-42404 ◽

2015 ◽

Author(s):

George Karabelas ◽

Geoff Redfern ◽

Brad Jacobs ◽

Andrew Roberts ◽

Upul Fernando ◽

...

Keyword(s):

Field Tests ◽

Root Cause Analysis ◽

Full Scale ◽

Acceptance Testing ◽

Cause Analysis ◽

Root Cause ◽

Subsequent Investigation ◽

Start Up ◽

Terra Nova ◽

Full Scale Tests

One riser and two flowline sections installed in the Suncor Energy Terra Nova riser replacement programme were shown to leak during field tests performed after site installation. No hydrocarbon loss occurred nor was there an environmental incident; however, the scheduled production start-up for the pipes was delayed. The pipes were designed and manufactured to comply with API [1] code and had successfully undergone full-scale factory acceptance testing (FAT) at 1.5 times design pressure following manufacture. Investigations confirmed that the leaks in both pipes occurred due to a crack in the polymer (PVDF) barrier within the end-fitting region of the pipe. It was also concluded that the crack in the barrier in these pipes occurred after completion of the FAT and sometime during the transportation, storage and subsequent installation of the pipes in the field. It was identified that the problem in the barrier resulted from an unknown thermo-mechanical loading condition of the pipe during this period, and also related to specific design features of some components in those end-fittings. The TapRoot Root Cause Analysis (RCA) tool was used to guide the investigation effort and consider all available data. Small and full-scale tests were performed to simulate and understand the end fitting design in the environments and conditions experienced during transport, installation and offshore testing. What is presented here is a brief outline of the incident and details of the subsequent investigation. The investigation was conducted over a period of 18 months with the participation of all parties involved in the design, manufacture, installation and operation of the flexibles. This paper summarises the investigation process followed, documents the results, discusses the results and outlines the conclusions and recommendations arising from this investigation.

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Theory and methods for calculating the inertial-braking characteristics of a ship

10.21303/978-617-7319-30-5 ◽

2020 ◽

Author(s):

Evgeny Kalinichenko

Keyword(s):

Linear Equations ◽

Field Tests ◽

Full Scale ◽

Computational Method ◽

Accident Rate ◽

Stopping Distance ◽

Motion Modes ◽

Scale Experiment ◽

Full Scale Tests ◽

First Time

One of the most serious problems of modern navigation is the accident rate that occurs due to inept or belated maneuvering of ships. As a result of accidents in the world, more than 200 ships die every year and every fourth receives significant damage. Full-scale tests show that the stopping distance of large-tonnage ships turn out to be much less permissible, and shipbuilders are able to significantly reduce the astern power of such ships, making them cheaper at the expense of safety. The low accuracy of inertial-braking characteristics is mainly due to unqualified field tests. Analysis of graphs and tables based on the results of such tests show that the spread in the values of inertial-braking characteristics for ships of the same type reaches 30%, and in some cases even more. In many tables and graphs, inertial-braking characteristics are expressed in relative values and are not suitable for direct use when maneuvering a ship. Finally, even when graphical and/or tabular maneuvering information is available on the navigating bridge, it is difficult to use it when maneuvering a ship at night. The research carried out by the author results in: - creation of an alternative computational method for determining the inertial-braking characteristics of the ship, suitable for use on any on-board computer; - development of an improved methodology for calculating the path and time of acceleration and braking of the ship in various ahead motion modes; - development of a methodology for taking into account the influence of a passing and opponent current on the length of the stopping distance of the ship; - development of methods for solving applied problems, ensuring a decrease in the accident rate of ships during maneuvering. The obtained methods include the development of theoretical foundations, mathematical models and comparison of the calculated inertial-braking characteristics of ships with the data of a full-scale experiment. For the first time, to derive the calculated formulas for the time and stopping distance, theorems are used on the change in the momentum and kinetic energy during accelerated and decelerated motion of the ship. In the course of the study, the problems of calculating and formalizing the inertial-braking characteristics of the ship are being comprehensively solved. For the first time, the hypothesis that the nature of the change in the thrust force of the propeller during reverse can be approximated by linear equations has been substantiated and confirmed. The general results are used to calculate the inertial-braking characteristics of specific ships.

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