Stand-Damage Model with Java (Version 3.0)

Coal burst occurrences are affected by a range of mining and geological factors. Excessive slipping between the strata layers may release a considerable amount of strain energy, which can be destructive. A competent strata is also more vulnerable to riveting a large amount of strain energy. If the stored energy in the rigid roof reaches a certain level, it will be released suddenly which can create a serious dynamic reaction leading to coal burst incidents. In this paper, a new damage model based on the modified thermomechanical continuum constitutive model in coal mass and the contact layers between the rock and coal mass is proposed. The original continuum constitutive model was initially developed for the cemented granular materials. The application of the modified continuum constitutive model is the key aspect to understand the momentum energy between the coal–rock interactions. The transformed energy between the coal mass and different strata layers will be analytically demonstrated as a function of the rock/joint quality interaction conditions. The failure and post failure in the coal mass and coal–rock joint interaction will be classified by the coal mass crushing, coal–rock interaction damage and fragment reorganisation. The outcomes of this paper will help to forecast the possibility of the coal burst occurrence based on the interaction between the coal mass and the strata layers in a coal mine.

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Cavitation-induced damage model of soft materials in exposure to high-intensity focused ultrasound

Acta Mechanica Sinica ◽

10.1007/s10409-020-01000-y ◽

2020 ◽

Vol 36 (5) ◽

pp. 1058-1064

Author(s):

Qinyi Huang ◽

Zheng Zhong

Keyword(s):

High Intensity ◽

Focused Ultrasound ◽

Damage Model ◽

Soft Materials ◽

High Intensity Focused Ultrasound

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Ductile Crack Extension Analysis for X80 Bending Deformation Using Damage-Based Model

Volume 4: Production Pipelines and Flowlines; Project Management; Facilities Integrity Management; Operations and Maintenance; Pipelining in Northern and Offshore Environments; Strain-Based Design; Standards and Regulations ◽

10.1115/ipc2014-33432 ◽

2014 ◽

Cited By ~ 1

Author(s):

Satoshi Igi ◽

Mitsuru Ohata ◽

Takahiro Sakimoto ◽

Kenji Oi ◽

Joe Kondo

Keyword(s):

Plastic Strain ◽

Simulation Model ◽

Crack Growth ◽

Crack Extension ◽

Damage Model ◽

Stress Triaxiality ◽

Crack Growth Behavior ◽

Ductile Crack ◽

Ductile Crack Growth ◽

Notch Tip

This paper presents experimental and analytical results focusing on the strain limit of X80 linepipe. Ductile crack growth behavior from a girth weld notch is simulated by FE analysis based on a proposed damage model and is compared with the experimental results. The simulation model for ductile crack growth accompanied by penetration through the wall thickness consists of two criteria. One is a criterion for ductile crack initiation from the notch-tip, which is described by the plastic strain at the notch tip, because the onset of ductile cracking can be expressed by constant plastic strain independent of the shape and size of the components and the loading mode. The other is a damage-based criterion for simulating ductile crack extension associated with damage evolution influenced by plastic strain in accordance with the stress triaxiality ahead of the extending crack tip. The proposed simulation model is applicable to prediction of ductile crack growth behaviors from a circumferentially-notched girth welded pipe with high internal pressure, which is subjected to tensile loading or bending (post-buckling) deformation.

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