A Comparison of Pull-Out Capacity of Suction Anchors in Clay and Sand

2014 ◽  
Vol 614 ◽  
pp. 613-617
Author(s):  
Jia Qing Du ◽  
Shou Ji Du ◽  
Zhi Wang
Keyword(s):  
Aspect Ratio ◽  
Oil And Gas ◽  
Three Dimensional ◽  
Extreme Environment ◽  
Soil Conditions ◽  
Analysis Method ◽  
Comparison Analysis ◽  
Pull Out ◽  
Rise Rate ◽  
Geological Conditions

With the oil and gas exploitation develop to the deep sea; offshore platform under extreme environment load needs more stable anchorage foundation. Based on the slender suction anchor of SPAR, three-dimensional numerical analysis method was presented to study the ultimate pull-out capacity. Based on the geological conditions from South China Sea, clay and sand was selected as soil conditions to make a comparison analysis. The effects of soil type, load positions, load angles and aspect ratio on the ultimate bearing pull-out resistance of the suction foundation were studied. The comparison analysis results indicated that the ultimate pull-out resistance of suction anchors in sand has a greater rise rate and achieve ultimate pull-out capacity need smaller displacement than in clay; load point and load angles have a great impact on the resistance and there is a critical aspect ratio under inclined loading in sand.

scholarly journals Non-Probabilistic Time-Varying Reliability-Based Analysis of Corroded Pipelines Considering the Interaction of Multiple Uncertainty Variables

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1965 ◽  
Author(s):  
Xiangqin Hou ◽  
Yihuan Wang ◽  
Peng Zhang ◽  
Guojin Qin
Keyword(s):  
Reliability Analysis ◽  
Oil And Gas ◽  
Three Dimensional ◽  
Time Varying ◽  
Reliability Model ◽  
Analysis Method ◽  
Reliability Method ◽  
Corrosion Defects ◽  
Probability Information ◽  
Safe Working

Reliability analysis of corroded pipelines is critical to the integrity and safe working of pipeline infrastructure. Aiming at less probability information is obtained for corrosion pipeline engineering, and the mechanical properties of pipeline with corrosion defects deteriorate caused by the accumulative effect of corrosion growth. Based on the quasi-static analysis method and non-probability theory, this paper presents a reliability model for assessing corroded pipelines with corrosion growth. In fact, reliability analysis of corroded pipelines needs to consider the interaction of multiple uncertainty variables. By introducing interaction theory, a mathematical model of corrosion defects considering the interaction of variables is put forward. Moreover, this paper develops a non-probabilistic time-varying reliability method for pipeline systems with multiple defects. Thus, several numerical examples are investigated to discuss the effectiveness of the proposed methodology. The results show that a two-dimensional or even three-dimensional ellipsoid model with correlation has more accurate results to evaluate corroded pipelines under the interaction of multiple corroded defects with poor information. Furthermore, a non-probabilistic time-varying reliability model is established according to the time-varying characteristics of the corroded pipeline under the influence of multiple factors. An effective complement to the theory of non-probabilistic reliability analysis of system is investigated. The analysis of the results suggests that interaction of corroded pipeline has a negligible impact on reliability. It also provides a theoretical basis for maintenance and is of great significance for risk- and reliability-informed decisions regarding buried oil and gas pipelines.

scholarly journals A Three-Dimensional Turbulent Flow Analysis Method for the Rotating Channels of a Centrifugal Turbomachine

1982 ◽  
Author(s):  
D. A. Fraser ◽  
J. H. G. Howard ◽  
W. C. Lennox
Keyword(s):  
Aspect Ratio ◽  
Turbulent Flow ◽  
Numerical Method ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Center Line ◽  
Analysis Method ◽  
Solution Methods

A three-dimensional turbulent flow analysis method is described based on transformations of the equations to follow an arbitrary curved passage center-line and allowing for passage area and aspect ratio variations. The numerical method is arranged to allow either parabolic or partially parabolic solution methods in the main passage direction. The method has been tested for radial turbomachine elements and comparisons are included with measured internal passage flows in a radial impeller.

scholarly journals EXPERIMENTAL TESTS OF A BEARING CAPACITY OF «FUNDEX» PILES AFTER THE LONG “RELAXATION” IN CLAY SOILS THE DEAD PRESSING AND PULLING-OUT LOADS

2019 ◽  
Vol 10 (2) ◽  
pp. 13-29
Author(s):  
A. V Savinov ◽  
V. E Frolov ◽  
Y. N Brovikov ◽  
M. P Kozhinskiy
Keyword(s):  
Bearing Capacity ◽  
Field Tests ◽  
Experimental Tests ◽  
Soil Conditions ◽  
Field Methods ◽  
Technical Science ◽  
Pull Out ◽  
Geological Conditions ◽  
Wide Range ◽  
The Dead

In the article analyzes the results of experimental tests of new “Fundex” piles for The City of Saratov. Сlassification of piles based on their interplay with the pile base has been devised by Doctor of Technical Science, Professor F.K. Lapshin. Changes introduced in 2016 into SP 24.13330.2011 “Pile foundations” concerning calculation of the displacing stuffed concrete piles. The short analysis of history of creation of tables SP 24.13330 by determination of rated resistance on a lateral area and under the lower end of piles is carried out. It is shown that these sizes are not the limit resistances at exhaustion of a carrying capacity of a soil at “failure”, and are accepted with some stock at achievement by a pile of “predetermined” settling. There has been noted the existence of a large number of piles testing methods by means of incrementally increasing load different from methodology GOST 5686-2012 “Soils. Methods of field trials of piles” by various assessment criteria of the ultimate pile bearing capacity. Two identical piles have been manufactured in identical soils and after a long (3 months) “relaxation” without load tests have been conducted under GOST 5686 with static indenting and pull out loads. Engineering-geological conditions of the platform and distance between piles excluded their interference at manufacture and tests. the dead pressing and pulling-out loads. Comparison of results of field tests of “Fundex” piles to design values of a bearing capacity of the displacing piles determined by the recommendations of SP 24.13330 is carried out. The essential divergence of the experimental and estimated values at assessment of a bearing capacity of a heel of a pile is noted. Conclusions are drawn on need of additional experimental research of the basis of “Fundex” piles for the wide range of soil conditions by laboratory and field methods with parallel tests static indenting and pull out loads.

COMBINED EFFECTS OF A GUN PROFILE AND SABOT ON THE STRENGTH OF PENETRATOR

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4517-4522
Author(s):  
JIN-BONG KIM
Keyword(s):  
Aspect Ratio ◽  
Three Dimensional ◽  
Transverse Force ◽  
Principal Factor ◽  
Combined Effects ◽  
Analysis Method ◽  
Element Analysis ◽  
Finite Element Analysis Method ◽  
Dynamic Finite Element ◽  
Dynamic Finite Element Analysis

As the projectile moves through the gun tube, the gun tube is subjected to a traveling load consisting of the weight of the projectile and a transverse force, probably much greater than the weight, due to the mass of the projectile being constrained to follow a curved path, defined by the shape of the gun tube. This is not simply the curvature of the barrel due to gravity, but the instantaneous value resulting from all the causes of vibration. The gun tube profile and properties of sabot may affects on strength on the penetrator traveling in the gun tube. In addition to these, the aspect ratio of penetrator is also the principal factor for the strength of penetrator. Combined influences of the forward sabot diameter and aspect ratio of penetrator on the strength of penetrator was analyzed using three dimensional dynamic finite element analysis method in the study.

A Three-Dimensional Turbulent Flow Analysis Method for the Rotating Channels of a Centrifugal Turbomachine

1983 ◽  
Vol 105 (3) ◽  
pp. 422-429 ◽  
Author(s):  
D. A. Fraser ◽  
J. H. G. Howard ◽  
W. C. Lennox
Keyword(s):  
Aspect Ratio ◽  
Turbulent Flow ◽  
Numerical Method ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Center Line ◽  
Analysis Method ◽  
Solution Methods

A three-dimensional turbulent flow analysis method is described based on transformations of the equations to follow an arbitrary curved passage center-line and allowing for passage area and aspect ratio variations. The numerical method is arranged to allow either parabolic or partially parabolic solution methods in the main passage direction. The method has been tested for radial turbomachine elements and comparisons are included with measured internal passage flows in a radial impeller.

Cryogels as a solution to the issues of environmental management and trunk pipeline operation in Arctic

2020 ◽  
Vol 10 (2) ◽  
pp. 173-185
Author(s):  
Lyubov K. Altunina ◽  
◽  
Vladimir P. Burkov ◽  
Petr V. Burkov ◽  
Vitaly Y. Dudnikov ◽  
...  
Keyword(s):  
Composite Materials ◽  
Field Experiments ◽  
Oil And Gas ◽  
Soil Layer ◽  
Soil Microflora ◽  
Russian Arctic ◽  
Thaw Cycle ◽  
Trunk Pipeline ◽  
Geological Conditions ◽  
Spatial Lattice

In the Russian Arctic, a soil cryostructuring technique (i.e. strengthening of soil horizons with cryogel-based composite materials with no excavation of unstable soils required) seems to be showing promise. Experiments have proven that mechanical and thermal insulation properties attributed to cryogels make them appropriate for use in strengthening and thermally insulating the soil, while their structure makes it possible to form a stable vegetation cover. Field experiments have confirmed that cryostructuring efficiently strengthens the soil layer with cryogels stimulating soil microflora. An experience of using cryotropic compositions in the oil and gas sector was described. Notably, cryogels can be used to strengthen unstable soil foundations of trunk pipelines, as well as to bind soil (e.g. on slopes). In addition, cryogels are advised for use in engineering protection to prevent the uneven settlement of a trench base and its creep: thus, cryogels are pumped into the soil of the trench bottom base to create a support system representing a spatial lattice. After the first freeze and thaw cycle, cryotropic material is formed and then increases its strength and elasticity with each new cycle. More broadly, opportunities have been considered regarding cryogels used in various engineering and geological conditions, while taking into account the outcomes of landscape and territorial analysis. It was concluded that cryogel-based composite materials are a promising innovative scientific field expanding technological capabilities for developing and using spaces and resources in the Russian Arctic.

SCAM: The Software Architecture Comparison Analysis Method

2003 ◽  
Author(s):  
Christopher Stoermer ◽  
Felix Bachmann ◽  
Chris Verhoef
Keyword(s):  
Software Architecture ◽  
Analysis Method ◽  
Comparison Analysis

scholarly journals Investigations of polyethylene of raised temperature resistance service performance using autoclave test under sour medium conditions

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 346-354
Author(s):  
Guoquan Qi ◽  
Hongxia Yan ◽  
Dongtao Qi ◽  
Houbu Li ◽  
Lushi Kong ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Mechanical Performance ◽  
Three Dimensional ◽  
Service Performance ◽  
Degree Of Branching ◽  
Temperature Resistance ◽  
Temperature Conditions ◽  
Dimensional Network ◽  
Gas Medium ◽  
Better Than

Abstract The chapter deals with the performance evaluation of the polyethylene of raised temperature resistance (PE-RT) and polyethylene (PE) using autoclave test under sour oil and gas medium conditions. The analyses of performance changes showed that PE-RT has good media resistance at 60°C. As the temperature increases, its mechanical properties decrease, accompanied by an increase in weight. Comparative analyses showed that no matter what temperature conditions are, PE-RT media resistance is better than PE80. The better media resistance of PE-RT depends on its higher degree of branching. Short branches are distributed between the crystals to form a connection between the crystals, thereby improving its heat resistance and stress under high-temperature conditions. PE-RT forms an excellent three-dimensional network structure through copolymerization, ensuring that it has better media resistance than PE80. However, the mechanical performance will be attenuated due to the high service temperature.

Sign in / Sign up

Export Citation Format

Share Document