Applicability of Mandrel Elbow to High Pressure Gas Pipeline

2014 ◽  
Author(s):  
Hiroyuki Horikawa ◽  
Hideo Toma ◽  
Yasuo Yabe ◽  
Mitsunori Tsukidate ◽  
Nobuhisa Suzuki
Keyword(s):  
High Pressure ◽  
Ground Deformation ◽  
Design Method ◽  
Limit State ◽  
Local Buckling ◽  
Lateral Spreading ◽  
Bending Test ◽  
Design Code ◽  
Seismic Design Code ◽  
Permanent Ground Deformation

Applicability of mandrel elbows to high pressure gas pipelines is discussed in this paper taking into account the seismic integrity to withstand liquefaction-induced permanent ground deformation. Bending test and FE analysis of X65, 45 deg. mandrel elbow with diameter of 24-in were conducted in order to evaluate the seismic integrity for lateral spreading due to liquefaction. Local buckling behaviors of the closing-mode test was simulated by FEA and calculation of existing seismic design code for high pressure pipelines can estimate maximum bending angle as limit state of the mandrel elbow conservatively. The results clarify that mandrel elbows can be applied to high pressure pipelines using conventional design method including the design code and FEA. In addition, buckling behaviors of the mandrel elbow were similar to those of high-frequency induction bends which have been used for high pressure pipelines in Japan.

Bridging the Gap Between Qualitative, Semi-Quantitative and Quantitative Risk Assessment of Pipeline Geohazards: The Role of Engineering Judgment

2015 ◽  
Author(s):  
R. S. Rod Read ◽  
Moness Rizkalla
Keyword(s):  
Ground Deformation ◽  
Lateral Spreading ◽  
Quantitative Risk Assessment ◽  
Assessment Approach ◽  
Assessment Engineering ◽  
Hazard And Risk ◽  
Pipeline Route ◽  
Permanent Ground Deformation ◽  
Fault Displacement

Geohazards are threats of a geological, geotechnical, hydrological or seismic/tectonic nature that can potentially damage pipelines and other infrastructure. Depending on the physiographic setting of a particular pipeline, a broad range of geohazards may be possible along the pipeline route. However, only a limited number of geohazards such as landslides, fault displacement, mining-induced subsidence, liquefaction-induced lateral spreading, and hydrological scour, which can result in permanent ground deformation or exposure of the pipeline to direct impact, typically represent credible threats to pipeline integrity. Identifying potential geohazard occurrences and estimating the likely severity of each occurrence in relation to pipeline integrity is an integral part of geohazard management, and overall risk management of pipelines. Methods for identifying and assessing the potential likelihood and severity of geohazards vary significantly, from purely expert judgment-based approaches relying largely on visual observations of geomorphology to analytically-intense methods incorporating phenomenological or mechanistic models and data from monitoring and field characterization. Each of these methods can be used to assess hazard and risk associated with specific geohazards in terms of qualitative, semi-quantitative, or quantitative expressions as long as uncertainty and assumptions are understood and communicated as part of the assessment. Engineering judgment is highlighted as an essential component to varying degrees of each geohazard assessment approach.

Seismic Evaluation of Existing Structures Supporting Loading-Arms in LNG Receiving Terminal

2002 ◽  
Author(s):  
Masami Oshima ◽  
Takashi Kase
Keyword(s):  
Seismic Design ◽  
Design Method ◽  
Seismic Loads ◽  
Seismic Evaluation ◽  
Design Code ◽  
Existing Structures ◽  
Seismic Design Code ◽  
Seismic Design Method ◽  
Level 2 ◽  
Coefficient Method

After Hyogo South Area earthquake, a new seismic design method considering non-elastic deformation behavior is established against Level 2 earthquake (Safety Shutdown Earthquake) in the Seismic Design Code of High-pressure Gas Facilities in Japan. In this paper, this method is applied for an evaluation of existing structures supporting loading-arms in LNG Receiving Terminal. A procedure of pre-earthquake seismic upgrading and modification of the structures that are supported by platforms and supporting loading-arms is introduced. In this evaluation, the seismic loads taking into account of interaction among platforms, structures, and loading-arms are analyzed as total systems. And yield strength design method is applied. Then for the seismic design of loading-arms, floor response spectrums on the installation level are presented. After upgrading the platforms in this case, seismic evaluation of loading-arms based on this study will be performed. So the effect of changing its stiffness is studied. Also to evaluate the dynamic loads subjected to the loading-arms, they are compared with seismic loads that are derived from modified static coefficient method of the seismic design code. Thus with studies of vibration characteristics as total systems, it is possible to make effective and economical countermeasures for pre-earthquake seismic upgrading and modification of the structures and loading-arms.

Deformation capacity of buried hybrid-segmented pipelines under longitudinal permanent ground deformation

2020 ◽  
Author(s):  
Gersena Banushi ◽  
Brad Wham
Keyword(s):  
Water Distribution ◽  
Large Scale ◽  
Ground Deformation ◽  
Lateral Spreading ◽  
Analytical Models ◽  
Axial Deformation ◽  
Pipe System ◽  
Pull Out ◽  
Pipeline Systems ◽  
Permanent Ground Deformation

Innovative hybrid-segmented pipeline systems are being used more frequently in practice to improve the performance of water distribution pipelines subjected to permanent ground deformation (PGD), such as seismic-induced landslides, soil lateral spreading, and fault rupture. These systems employ joints equipped with anti-pull-out restraints, providing the ability to displace axially, before locking up and behaving as a continuous pipeline. To assess the seismic response of hazard-resistant pipeline systems equipped with enlarged joint restraints to longitudinal PGD, this study develops numerical and semi-analytical models, considering the nonlinear properties of the system, calibrated from large-scale test data. The deformation capacities of two hybrid-segmented pipelines are investigated: (1) hazard-resilient ductile iron (DI) pipe, and (2) oriented polyvinylchloride (PVCO) pipe with joint restraints capable of axial deformation. The numerical analysis demonstrates that, for the conditions investigated, the maximum elongation capacity of the analyzed DI pipe system is greater than that of the PVCO pipeline. The implemented semi-analytical approach revealed that the pipeline performance strongly improves by increasing the allowable joint displacement. Comparison of the numerical results with analytical solutions reported in recent research publications showed excellent agreement between the two approaches, highlighting the importance of assigning appropriate axial friction parameters for these systems.

Development of Seismic Design Code for High Pressure Gas Facilities in Japan

2004 ◽  
Vol 126 (1) ◽  
pp. 2-8 ◽  
Author(s):  
Heki Shibata ◽  
Kohei Suzuki ◽  
Masatoshi Ikeda
Keyword(s):  
High Pressure ◽  
Seismic Performance ◽  
Seismic Design ◽  
Design Code ◽  
Ground Failure ◽  
Gas Leakage ◽  
Design Practices ◽  
Seismic Design Code ◽  
Level 1 ◽  
Level 2

The Seismic Design Code for High Pressure Gas Facilities was established in 1982 in advance of those in other industrial fields, the only exception being that for nuclear power plants. In 1995, Hyogoken Nanbu earthquake caused approximately 6000 deaths and more than $1 billion (US) loss of property in the Kobe area, Japan. This unexpected disaster underlined the idea that industrial facilities should pay special consideration to damages including ground failure due to the liquefaction. Strong ground motions caused serious damage to urban structures in the area. Thus, the Seismic Design Code of the High Pressure Gas Facilities were improved to include two-step design assessments, that is, for Level 1 earthquakes (operating basis earthquake: a probable strong earthquake during the service life of the facilities), and Level 2 earthquakes (safety shutdown earthquake: a possible strongest earthquake with extremely low probability of occurrence). For Level 2 earthquakes, ground failure by possible liquefaction will be taken into account. For a Level 1 earthquake, the required seismic performance is that the system must remain safe without critical damage after the earthquake, including no gas leakage. For a Level 2 earthquake, the required seismic performance is that the system must remain safe without gas leakage. This means a certain non-elastic deformation without gas leakage may be allowed. The High Pressure Gas Safety Institute of Japan set up the Seismic Safety Promotion Committee to modify their code, in advance of other industries, and has continued to investigate more effective seismic design practices for more than 5 years. The final version of the guidelines has established design practices for the both Level 1 and Level 2 earthquakes. In this paper, the activities of the committee, their new design concepts and scope of applications are explained.

Experimental Research on Ultimate Bending Capacity of Reinforced Concrete Poles in Service Period

2011 ◽  
Vol 368-373 ◽  
pp. 2468-2472
Author(s):  
Kai Quan Xia ◽  
Ni Wang ◽  
Zong Ping Chen ◽  
Ming Zhong
Keyword(s):  
Reinforced Concrete ◽  
Crack Width ◽  
Failure Modes ◽  
Design Method ◽  
Limit State ◽  
Bending Test ◽  
Experiment Data ◽  
Reinforced Beams ◽  
Service Period ◽  
Bending Capacity

In order to evaluate safety performance of reinforced concrete poles accurately, 6 reinforced concrete pole specimens were selected randomly for the bending test. The mechanical behavior and failure mechanism of all specimens were studied, failure modes were revealed, and important experiment data were also obtained, such as cracking loading, ultimate loading, crack development shape, crack width and so on. Based on the experiment data, moment-crack width relationship curve and moment-deflection relationship curve were obtained. Research results showed that failure modes of specimens were similar to “less-reinforced beams”, based on limit state design method in normal use, security surplus factor is 1.27 before collapse damage.

Developments of Seismic Design Code for High Pressure Gas Facilities in Japan

2002 ◽  
Author(s):  
Heki Shibata ◽  
Kohei Suzuki ◽  
Masatoshi Ikeda
Keyword(s):  
High Pressure ◽  
Seismic Design ◽  
Power Plants ◽  
Design Code ◽  
Seismic Safety ◽  
Ground Failure ◽  
Gas Leakage ◽  
Seismic Design Code ◽  
Level 1 ◽  
Level 2

The Seismic Design Code for High Pressure Gas Facilities was established in advance of other industrial fields in 1982. Only exception was that for nuclear power plants. In 1995, Hyogoken Nanbu earthquake brought approximately 6,000 deaths and more than 100,000 M$ loss or property in Kobe area, Japan. This unexpected serious event enforced us that industrial facilities should pay to special considerations of their damages including ground failure due to the liquefaction. Their strong ground motions brought serious damages to urban structures in the area. Thus, the Seismic Design Code of the High Pressure Gas Facilities were improved to include 2 step design assessments, that is, Level 1 earthquake (operating basisearthquake, the probable strong earthquake in the service life of the facilities), and Level 2 earthquake (safety shutdownearthquake, the possible strongest earthquake with extremely low probability of occurrence). For Level 2 earthquake, the ground failure by possible liquefaction shall be taken into account. In regard to Level 1 earthquake, the system must be remained safety without critical damage after the earthquake, in addition to no leakage of “gas”. In regard to Level 2 earthquake, the required seismic performance is that peventing systems must be remained without gas leakage, and stable. It means a certain non-elastic deformation without gas leakage may be allowed. The High Pressure Gas Safety Institute of Japan has set up the Seismic Safety Promotion Committee to modify their code in advance of other industries, and continue to investigate more reasonable seismic design practice for more than 5 years. Andthe final version of the guideline has been established for the design practices both in Level 1 and Level 2 earthquakes. This paper explains the activities of the committee, their new design concepts and scope of applications.

Deformation Capacity of Weld Seam of the High Quality HFW Linepipe

2015 ◽  
Author(s):  
Satoshi Igi ◽  
Satoru Yabumoto ◽  
Teruki Sadasue ◽  
Hisakazu Tajika ◽  
Kenji Oi
Keyword(s):  
Low Temperature ◽  
Internal Pressure ◽  
Seismic Design ◽  
Weld Seam ◽  
Full Scale ◽  
Bending Test ◽  
Design Code ◽  
High Quality ◽  
Seismic Design Code ◽  
Full Scale Tests

Newly-developed high quality high frequency electric resistance welded (HFW) linepipes have recently been used in pipelines in reel-lay applications and low temperature service environments because of their excellent low temperature weld toughness and cost effectiveness. In order to clarify the applicability of these HFW linepipes to the seismic environment, a series of full-scale tests such as bending test with internal pressure and uniaxial compression test were conducted according to the seismic design code in Japan gas association (JGA). Based on the above-mentioned full-scale tests, the safety performance of high quality HFW linepipe to apply to the seismic region is discussed in comparison with the mechanical properties in the small-scale tests such as the tensile and compression property of the base material and weld seam, especially focused on the strain capacity of HFW linepipe from the view points of full-scale performance and geometrical imperfection. Test results of the bending test with internal pressure and the uniaxial compression were complied with the JGA seismic design code for the permanent ground deformation induced by lateral spreading and surface faults.

Strain Capacity and Deformation Behavior of HFW Linepipe

2016 ◽  
Author(s):  
Satoshi Igi ◽  
Satoru Yabumoto ◽  
Teruki Sadasue ◽  
Hisakazu Tajika ◽  
Kenji Oi
Keyword(s):  
Internal Pressure ◽  
Seismic Design ◽  
Full Scale ◽  
Bending Test ◽  
Uniaxial Compression Test ◽  
Design Code ◽  
Strain Capacity ◽  
Seismic Design Code ◽  
Full Scale Tests ◽  
Tensile Strain Capacity

Newly-developed high quality high frequency electric resistance welded (HFW) linepipes have recently been applied to offshore pipelines by using the reel-lay method and onshore in extremely low temperature environments because of their excellent low temperature weld toughness and cost effectiveness. In order to clarify the applicability of these HFW linepipes to seismic regions, a series of full-scale tests such as the bending test with internal pressure and the uniaxial compression test were conducted according to the seismic design code of the Japan Gas Association (JGA). Based on these full-scale tests, the safety performance of high quality HFW linepipe when applied to seismic regions is discussed in comparison with the mechanical properties obtained in small-scale tests, such as the tensile and compression properties of the base material and weld seam, focusing especially on the compressive and tensile strain capacity of HFW linepipes from the viewpoints of full-scale performance and geometrical imperfections. The results of the bending test under internal pressure and the uniaxial compression test without internal pressure complied with the JGA seismic design code for permanent ground deformation induced by lateral spreading and surface faults. In addition, a full-pipe tension test was also conducted in order to investigate the tensile strain capacity of HFW linepipes for axial deformation.

scholarly journals Graphical tool for assessing the critical temperatures of steel beams and columns in fire

Fire Research ◽  
2018 ◽  
Author(s):  
Valdir Pignatta Silva ◽  
Arthur Ribeiro Melão ◽  
Igor Pierin
Keyword(s):  
Critical Temperature ◽  
Design Method ◽  
Limit State ◽  
Local Buckling ◽  
Steel Beams ◽  
Ultimate Limit State ◽  
Structural Element ◽  
Critical Temperatures ◽  
Graphical Tool ◽  
In Fire

In a fire situation, the temperature in which the ultimate limit state of the structural element is reached is called critical temperature. It is very laborious to determine it. The aim of this work was to create a graphical tool to allow quick determination of the critical temperature of I shaped columns and beams without local buckling. The method used was based on the Brazilian standard and using AcoInc software developed by the authors. The result was a tool whose similarity was not found in the literature. The use of the tool developed in this study simplifies the use of the standardized design method. One conclusion to be highlighted is one in which constants values of the critical temperature, generally accepted in practice, may be unsafe.

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