Safety Analysis of Lining Structure Influenced by Blasting of Tunnel with Extralarge Section and Small Space

In order to ensure the safety of the Daling tunnel with extralarge section and small space, the three-dimensional model of blasting dynamic simulation had been established and verified. Then, the model was used to analyze the influence of the surrounding rock characteristics and blasting design parameters on the blasting vibration of the first hole, and the analysis of the sensitivity of each factor was carried out. The results showed that blasting of the second hole had a serious impact on the safety of the first hole lining structure. Based on the safety threshold and analysis of sensitivity, the explosive velocity, charge density, and digging length were selected as the key parameters affecting the safety of the tunnel structure. Meanwhile, the corresponding engineering measure was taken based on the results of sensitivity and the actual situation on site, and, after that, the maximum PPV of the right wall of the first hole had been reduced to 9.3 cm/s, which effectively guaranteed the safe construction of the tunnel.

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Blast load simulation using conical shock tube systems

International Journal of Protective Structures ◽

10.1177/2041419619858098 ◽

2019 ◽

Vol 11 (2) ◽

pp. 135-158 ◽

Cited By ~ 1

Author(s):

Ahmed Ismail ◽

Mohamed Ezzeldin ◽

Wael El-Dakhakhni ◽

Michael Tait

Keyword(s):

Shock Tube ◽

Three Dimensional ◽

Design Parameters ◽

Civil Infrastructure ◽

Two Dimensional ◽

Blast Loads ◽

Dimensional Model ◽

Tube System ◽

Three Dimensional Model ◽

Conical Shock

With the increased frequency of accidental and deliberate explosions, evaluating the response of civil infrastructure systems to blast loading has been attracting the interests of the research and regulatory communities. However, with the high cost and complex safety and logistical issues associated with field explosives testing, North American blast-resistant construction standards (e.g. ASCE 59-11 and CSA S850-12) recommend the use of shock tubes to simulate blast loads and evaluate relevant structural response. This study first aims at developing a simplified two-dimensional axisymmetric shock tube model, implemented in ANSYS Fluent, a computational fluid dynamics software, and then validating the model using the classical Sod’s shock tube problem solution, as well as available shock tube experimental test results. Subsequently, the developed model is compared to a more complex three-dimensional model and the results show that there is negligible difference between the two models for axisymmetric shock tube performance simulation; however, the three-dimensional model is necessary to simulate non-axisymmetric shock tubes. Following the model validation, extensive analyses are performed to evaluate the influences of shock tube design parameters (e.g. the driver section pressure and length and the expansion section length) on blast wave characteristics to facilitate a shock tube design that would generate shock waves similar to those experienced by civil infrastructure components under blast loads. The results show that the peak reflected pressure increases as the driver pressure increases, while a decrease in the expansion length increases the peak reflected pressure. In addition, the positive phase duration increases as both the driver length and expansion length are increased. Finally, the developed two-dimensional axisymmetric model is used to optimize the dimensions of a physical large-scale conical shock tube system constructed for civil infrastructure component blast response evaluation applications. The capabilities of such shock tube system are further investigated by correlating its design parameters to a range of explosion threats identified by different hemispherical TNT charge weight and distance scenarios.

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Techno-Determinism in Private Law: Influence of Bioprinting on Developing the Concept of Protecting the Right to Digital Image

Вестник Пермского университета Юридические науки ◽

10.17072/1995-4190-2020-50-678-704 ◽

2020 ◽

pp. 678-704

Author(s):

D. E. Bogdanov

Keyword(s):

Digital Image ◽

Three Dimensional ◽

Private Law ◽

Tort Liability ◽

European Law ◽

Dimensional Model ◽

Three Dimensional Model ◽

Human Right ◽

The Right ◽

Fault Liability

Introduction: the new technological revolution became a trigger in the development of the non-pecuniary benefits concept. In the context of digital transformation, personal privacy protection appears to be a serious problem. A person is found to be in a vulnerable position facing challenges of the new digital reality. This could be illustrated by the example of bioprinting since this technology is connected with digitalization of the human body and creation of its digital three-dimensional model. As a result, a person is becoming dependent on their three-dimensional digital embodiment in implementing their rights to life and health. Evolution in the concept of the right to personal image through recognition of the right to digital image appears as the private law response to the technological challenges. Purpose: to identify and analyze the major problems related to protection of the human right to digital image in bioprinting, as well as to determine an effective model of tort liability for encroachment on the personal digital image associated with the use of bioprinting technologies. Methods: dialectical, formal logical, functional, and other general scientific research methods, as well as special legal methods, including comparative legal and formal legal techniques. Results: the author has studied legal and philosophical problems associated with the bioprinting technology influence on the concept of protecting non-pecuniary benefits and its development; identified a trend associated with the evolution of the human right to digital image; considered the models of tort liability for encroachment on the personal digital image in European law in the comparative legal aspect; formulated prognostic conclusions concerning the model of liability for damage caused by violation of the right to digital image in Russian law. Conclusions: information about a person objectified in a digital three-dimensional model (CAD-file) deserves special protection. The possibility of access and use of such information about a person creates serious risks of causing damage to them. A person’s vulnerable position in bioprinting technologies indicates the need to recognize an absolute non-pecuniary right with a person to their digital image registered in the corresponding digital model (CAD-file). The philosophical and legal concept of human vulnerability serves as a theoretical foundation for the elaboration of solutions aimed at creating an efficient set of tools for protecting the human right to digital image. This concept was manifested in the European law in expanding the possibility of compensation for non-pecuniary damage, its presumption in case of encroachment on non-pecuniary benefits, as well as establishment of the no-fault liability standard. It is necessary to introduce in Russian legislation a special tort establishing the no-fault liability standard for damage caused by encroachment on a personal digital image. Presumption of moral damage in such encroachments, as well as the possibility of recovering exemplary damages from a delinquent, would correspond to the goals of general and special prevention.

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McPherson Suspension Simulation Analysis Method Based on ADAMS

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.860 ◽

2012 ◽

Vol 268-270 ◽

pp. 860-865

Author(s):

Xing Jia Yao ◽

Cheng Yin Xu ◽

Tie Qiang Ma ◽

Xiao Tong Zhang

Keyword(s):

Simulation Analysis ◽

Three Dimensional ◽

Design Parameters ◽

Vehicle Suspension ◽

Analysis Method ◽

Dimensional Model ◽

Three Dimensional Model ◽

Front Suspension ◽

The Common ◽

Vehicle Suspension System

In order to improve vehicle driving function, the author establishes a three-dimensional model of a sedan McPherson front suspension with ADAMS / CAR, besides, there is an analysis on the wheel vertical beating positioning parameter variation of the suspension when driving. With the evaluation of the rationality of the suspension design parameters, reaching the common method for the analysis and optimization of the vehicle suspension based on ADAMS, by which, we can improve the function of the vehicle suspension system, and save time to design the vehicle suspension.

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Optimize Design on the Key Parts of Ring Die Fuel Pellet Machine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.860-863.2707 ◽

2013 ◽

Vol 860-863 ◽

pp. 2707-2711

Author(s):

Wei Gao ◽

Qing Yu Liu ◽

Rong Fei Zhao ◽

Shi Yang Gu

Keyword(s):

Fatigue Damage ◽

Production Efficiency ◽

Three Dimensional ◽

Dynamics Simulation ◽

Fuel Pellet ◽

Design Parameters ◽

Dimensional Model ◽

Three Dimensional Model ◽

Unit Output ◽

Die Service Life

This paper analyzes the problems existing in the design and operation of ring die fuel pellet machine, and proposed to optimize the key parts. Determine the reasonable number of roller on the theory of fatigue damage after drawing up the related design parameters of ring die and the roller, a three-dimensional model of the link mold pellet machine is established using Pro/E soft-ware, and transferred the model into ADAMS software through Mech/Pro which dedicated interface software, then used ADAMS to make a dynamics simulation. Through calculation, the stress amplitude impact on the ring die and the Energy consumption per unit output are smallest when roller number is four. So, ring die service life and equipment production efficiency can be improved effectively through setting up reasonable roller number. Keywords-fuel pellet machine; roller; ring die; fatigue damage; three-dimensional model; dynamics simulation

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Oil Film Temperature Field Simulation of Hydrostatic Center Rack of Heavy-Duty Horizontal Boring Lathe

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.1578 ◽

2011 ◽

Vol 71-78 ◽

pp. 1578-1581

Author(s):

Jun Peng Shao ◽

Chong Li ◽

Xiao Qiu Xu ◽

Xiao Dong Yu ◽

Bo Wu ◽

...

Keyword(s):

Finite Element ◽

Three Dimensional ◽

Element Model ◽

Dimensional Model ◽

Three Dimensional Model ◽

Distribution Law ◽

Element Analysis ◽

Oil Film ◽

The Right ◽

Icem Cfd

In order to research the temperature distribution law of the interstitial oil film on the hydrostatic center rack, the interstitial oil film on the hydrostatic center rack is taken as the research subject. Firstly, a three-dimensional model of the interstitial oil film is built by UG software. Secondly, the constructed three-dimensional model is meshed by ICEM CFD software. Lastly, the constructed finite element model is simulated using the finite element analysis software ANSYS CFX. The results of the simulation show that the temperature near the oil seal edge is higher than oil chamber and oil-returning slot. If the shaft parts rotate clockwise, the temperature of the right high-temperature zone is higher than the left. The research results provide a theoretical basis for the research on the thermal distortion of the middle pillow.

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