Triple-hull ships with small water-plane area: Towing test results and some full-scale comparisons

The results of unique experimental studies of the strength and service life of a metal-composite high-pressure tank are presented. The goal of the study is to analyze the fracture mechanisms and evaluate the strength characteristics of the structure. The methodology included tests of full-scale samples of the tank for durability under short-term static, long-term static and cyclic loading with internal pneumatic pressure. Generalized test results and data of visual measurements, instrumental and acoustic-emission control of deformation processes, accumulation of damages and destruction of full-scale tank samples are presented. Analysis of the strength and stiffness of the structure exposed to internal pneumatic pressure is presented. The types of limiting states of the tanks have been established experimentally. Change in the stress-strain state of the tank under cyclic and prolonged static loading is considered. Specific features of the mechanisms of destruction of a metal-composite tank are determined taking into account the role of strain of the metal liner. The calculated and experimental estimates of the energy potential of destruction and the size of the area affected upon destruction of the tank are presented. Analysis of test results showed that the tank has high strength and resource characteristics that meet the requirements of the design documentation. The results of the experiments are in good agreement with the results of numerical calculations and analysis of the stress-strain state and mechanisms of destruction of the metal-composite tank.

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Predicting Roof Diaphragm and Endwall Stiffness From Full-Scale Test Results of a Metal-Clad, Post-Frame Building

Transactions of the ASAE ◽

10.13031/2013.28690 ◽

1992 ◽

Vol 35 (3) ◽

pp. 977-985 ◽

Cited By ~ 2

Author(s):

K. G. Gebremedhin ◽

J. A. Bartsch ◽

M. C. Jorgensen

Keyword(s):

Full Scale ◽

Test Results ◽

Full Scale Test ◽

Frame Building ◽

Scale Test

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Test results of full-scale high temperature superconductors cable models destined for a 36 kV, 2 kArms utility demonstration

Physica C Superconductivity ◽

10.1016/s0921-4534(01)00502-0 ◽

2001 ◽

Vol 357-360 ◽

pp. 1241-1244 ◽

Cited By ~ 1

Author(s):

M. Däumling ◽

C.N. Rasmussen ◽

F. Hansen ◽

D.W.A. Willén ◽

O.E. Schuppach ◽

...

Keyword(s):

High Temperature ◽

High Temperature Superconductors ◽

Full Scale ◽

Test Results

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Benchmarking of Truss Spar Vortex Induced Motions Derived From CFD With Experiments

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 3 ◽

10.1115/omae2005-67252 ◽

2005 ◽

Cited By ~ 6

Author(s):

John Halkyard ◽

Senu Sirnivas ◽

Samuel Holmes ◽

Yiannis Constantinides ◽

Owen H. Oakley ◽

...

Keyword(s):

Scale Up ◽

Vertical Cylinder ◽

Reynolds Numbers ◽

Full Scale ◽

Scale Model ◽

Current Direction ◽

Test Results ◽

Helical Strakes ◽

Truss Spar ◽

Scale Data

Floating spar platforms are widely used in the Gulf of Mexico for oil production. The spar is a bluff, vertical cylinder which is subject to Vortex Induced Motions (VIM) when current velocities exceed a few knots. All spars to date have been constructed with helical strakes to mitigate VIM in order to reduce the loads on the risers and moorings. Model tests have indicated that the effectiveness of these strakes is influenced greatly by details of their design, by appurtenances placed on the outside of the hull and by current direction. At this time there is limited full scale data to validate the model test results and little understanding of the mechanisms at work in strake performance. The authors have been investigating the use of CFD as a means for predicting full scale VIM performance and for facilitating the design of spars for reduced VIM. This paper reports on the results of a study to benchmark the CFD results for a truss spar with a set of model experiments carried out in a towing tank. The focus is on the effect of current direction, reduced velocity and strake pitch on the VIM response. The tests were carried out on a 1:40 scale model of an actual truss spar design, and all computations were carried out at model scale. Future study will consider the effect of external appurtenances on the hull and scale-up to full scale Reynolds’ numbers on the results.

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Launching of Ships and Floating Structures from Horizontal Berth by Tipping Table

Journal of Ship Production ◽

10.5957/jsp.1998.14.4.265 ◽

1998 ◽

Vol 14 (04) ◽

pp. 265-276

Author(s):

Ivo Senjanovic

Keyword(s):

Structural Dynamics ◽

Review Paper ◽

Offshore Structures ◽

Model Tests ◽

Full Scale ◽

Strength Analysis ◽

Test Results ◽

Floating Structures ◽

Measurement Results

This review paper covers extensive investigations which were undertaken in order to verify the idea of launching of ships and other floating structures from a horizontal berth by a set of turning pads. This includes structural dynamics during launching, model tests and strength analysis of the structure and the launching system. The most important results, which were used for the design of the launching system, are presented. The preparation of a barge for side launching is described, and the full-scale measurement results are compared with the test results. The advantages of building ships and offshore structures on a horizontal berth are pointed out in the conclusion.

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STUDY OF THE FIRE PERFORMANCE OF HYBRID STEEL-TIMBER CONNECTIONS WITH FULL-SCALE TESTS AND FINITE ELEMENT MODELLING

Applications of Structural Fire Engineering ◽

10.14311/asfe.2015.039 ◽

2016 ◽

Author(s):

Aaron O. Akotuah ◽

Sabah G. Ali ◽

Jeffrey Erochko ◽

Xia Zhang ◽

George V. Hadjisophocleous

Keyword(s):

Finite Element ◽

Load Ratio ◽

Full Scale ◽

Test Results ◽

Structural Members ◽

Fire Performance ◽

Shear Connection ◽

Timber Connections ◽

Full Scale Tests ◽

Connection Design

Connection design is critical in timber buildings since the connections tend to have lower strength than the structural members themselves and they tend to fail in a brittle manner. The effect of connection geometry on the fire performance of a hybrid steel-timber shear connection is investigated by full-scale testing. These tests were conducted by exposing the test specimens to the standard time-temperature curve defined by CAN/ULC-S101 (CAN/ULC-S101, 2007). Test results showed that the fire resistance of these connections depends on the load ratio, the type of connection and the relative exposure of the steel plate to fire. Finite element models of the connections under fire were constructed using ABAQUS/CAE and these were validated using the test results. These numerical model results correlate well with test results with ±8.32% variation.

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A COMPARISON BETWEEN MODEL AND PROTOTYPE WAVES IN HARBOURS

Coastal Engineering Proceedings ◽

10.9753/icce.v16.38 ◽

1978 ◽

Vol 1 (16) ◽

pp. 38

Author(s):

Sverre Bjordal ◽

Alf Torum

Keyword(s):

Physical Model ◽

Model Test ◽

Field Measurements ◽

Full Scale ◽

Common Method ◽

Test Results ◽

Open Coast ◽

The World ◽

Mooring Forces ◽

Absolute Basis

A common method of estimating the sheltering effects of different breakwater locations and layouts is to carry out physical model wave disturbance tests. Such tests have been carried out in different laboratories throughout the world for many years. But to our knowledge no reports are available in the literature showing comparison between model measurements and field measurements. The trend is that we know more and more on the wave cl imate along our coasts. Hence we have a better basis to make our economical calculations on breakwaters. We therefore also want to operate our models on a more absolute basis rather than on a comparative basis. The trend in recent years has also been to study breakwater locations and layouts in order to minimize mooring forces and ship movements. On this background VHL found a comparison between model test results and field measurements necessary. Full scale measurements of waves were carried out in two harbours by VHL during the winter 1976/77. This paper will present the results of the comparison of the model and the full scale measurements in Berlevag and Vard0 fishing harbours on the open coast of Finnmark in the northern part of Norway (Fig. I) . The model tests, as well as the full scale measurements, have been sponsored by the Norwegian State Harbour Authorities.

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A study into the scale effect on the strength properties of polymer composite materials

Nuclear Energy and Technology ◽

10.3897/nucet.5.35797 ◽

2019 ◽

Vol 5 (2) ◽

pp. 103-108

Author(s):

Valentina V. Kiryushina ◽

Yuliya Yu. Kovaleva ◽

Petr A. Stepanov ◽

Pavel V. Kovalenko

Keyword(s):

Composite Materials ◽

Polymer Composite ◽

Scale Effect ◽

Mechanical Characteristics ◽

Full Scale ◽

Sample Thickness ◽

Polymer Composite Materials ◽

Test Machine ◽

Test Results ◽

Laboratory Sample

Polymer composite materials (PCM) are used extensively and are viewed as candidates for application in various industries, including nuclear power. Despite a variety of methods and procedures employed to investigate the mechanical characteristics of PCMs, the use of the laboratory sample mechanical test results to design and model large-sized structures is not always fully correct and reasonable. In particular, one of the problems is concerned with taking into account the scale parameter effects on the PCM strength and elastic characteristics immediately in the product. The purpose of the study is to investigate the scale effects on the mechanical characteristics of glass reinforced plastics using phenolformaldehyde and silicon-organic binders and a fabric quartz filler. Samples of four different standard sizes under GOST 25604-82 and GOST 4648-2014 were tested for three-point bending using an LFM-100 test machine to estimate the scale effect. The thicknesses of the model samples were chosen with regard for the wall thicknesses of full-scale products under development or manufactured commercially and the test machine features, and varied in the limits of 1.6 to 7.5 mm. The tests showed that strength decreased as the sample thickness was increased to 3 mm and more both at room and elevated (200 to 500 °C) temperatures, which can be described by an exponential function based on the Weibull statistical model. The values of the Weibull modulus that characterizes the extent of the scale effect on the strength of the tested materials were 4.6 to 6.7. The average bend strength in the sample thickness range of 3 mm and less does not vary notably or tends to increase slightly as the thickness is increased. This fact makes it possible to conclude that estimation of allowable stresses in a thin-wall product requires the use of test results for samples with a thickness that is equal to the product wall thickness since standard samples may yield overestimated allowable stress values and lead, accordingly, to incorrect calculations of the strength factor. The results obtained shall be taken into account when defining the allowable levels of operation for full-scale products and structures of polymer composites based on the laboratory sample strength data as well as when estimating their robustness as a characteristic of the product’s fail-safe operation.

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