Sinusoidal buckling behaviour of surface casing with negative friction in thawing permafrost

2021 ◽  
pp. 109616
Author(s):  
Peixin Sun ◽  
Tingting Luo ◽  
Baosheng Wang ◽  
Weihao Yang
Keyword(s):  
Negative Friction ◽  
Thawing Permafrost ◽  
Sinusoidal Buckling

Discharge-pulse Geotechnical Electro Discharge Technology of Bases Strengthening

2020 ◽  
Vol 787 (12) ◽  
pp. 63-65
Author(s):  
N.S. Sokolov
Keyword(s):  
Bearing Capacity ◽  
Mechanical Characteristics ◽  
Discharge Pulse ◽  
Zero Values ◽  
Traditional Technologies ◽  
Negative Friction ◽  
Geotechnical Problems ◽  
Physical And Mechanical Characteristics

The problem of increasing the bearing capacity of the base is an relevant problem in modern geotechnical construction. When significant loads are transmitted to the base, the use of traditional technologies is not always justified. Often there is an urgent need to use non-standard ways to strengthen the bases. In many cases, the geotechnical situation is aggravated by the presence of weak underlying layers with unstable physical and mechanical characteristics in engineering-geological sections. When strengthening such bases with the help of traditional piles, the latter can get negative friction, which significantly reduces their bearing capacity on the ground, sometimes reaching zero values. This may lead to additional precipitations of the objects being constructed and constructed in the zone of geotechnical influence. The use of ERT piles in most cases successfully solves many complex geotechnical problems.

scholarly journals Aged soils contribute little to contemporary carbon cycling downstream of thawing permafrost peatlands

2021 ◽  
Author(s):  
Andrew J Tanentzap ◽  
Katheryn Burd ◽  
McKenzie Kuhn ◽  
Cristian Estop‐Aragonés ◽  
Suzanne E. Tank ◽  
...  
Keyword(s):  
Carbon Cycling ◽  
Thawing Permafrost

scholarly journals Thawing Permafrost in Arctic Coastal Communities: A Framework for Studying Risks from Climate Change

2021 ◽  
Vol 13 (5) ◽  
pp. 2651
Author(s):  
Joan Nymand Larsen ◽  
Peter Schweitzer ◽  
Khaled Abass ◽  
Natalia Doloisio ◽  
Susanna Gartler ◽  
...  
Keyword(s):  
Risk Management ◽  
Risk Perception ◽  
Stakeholder Involvement ◽  
Coastal Communities ◽  
Mitigation Strategies ◽  
Socially Constructed ◽  
Local Stakeholders ◽  
Risk Framework ◽  
Relevant Stakeholder ◽  
Thawing Permafrost

Thawing permafrost creates risks to the environment, economy and culture in Arctic coastal communities. Identification of these risks and the inclusion of the societal context and the relevant stakeholder involvement is crucial in risk management and for future sustainability, yet the dual dimensions of risk and risk perception is often ignored in conceptual risk frameworks. In this paper we present a risk framework for Arctic coastal communities. Our framework builds on the notion of the dual dimensions of risk, as both physically and socially constructed, and it places risk perception and the coproduction of risk management with local stakeholders as central components into the model. Central to our framework is the importance of multidisciplinary collaboration. A conceptual model and processual framework with a description of successive steps is developed to facilitate the identification of risks of thawing permafrost in a collaboration between local communities and scientists. Our conceptual framework motivates coproduction of risk management with locals in the identification of these risks from permafrost thaw and the development of adaptation and mitigation strategies.

Thawing permafrost alters nematode populations and soil habitat characteristics in an Antarctic polar desert ecosystem

Pedobiologia ◽  
2012 ◽  
Vol 55 (2) ◽  
pp. 75-81 ◽  
Author(s):  
T.E. Smith ◽  
D.H. Wall ◽  
I.D. Hogg ◽  
B.J. Adams ◽  
U.N. Nielsen ◽  
...  
Keyword(s):  
Habitat Characteristics ◽  
Desert Ecosystem ◽  
Polar Desert ◽  
Thawing Permafrost ◽  
Soil Habitat

A Study of the Effects of Negative Friction-Speed Slope on Brake Squeal

1995 ◽  
Author(s):  
Yongbin Yuan
Keyword(s):  
Degrees Of Freedom ◽  
Element Model ◽  
Compression Modulus ◽  
Brake Squeal ◽  
Single Degree Of Freedom ◽  
Beam Elements ◽  
Negative Friction ◽  
Unstable Vibration ◽  
Almost All ◽  
Friction Induced Vibration

Abstract Brake squeal is caused by friction-induced vibration of brake systems. It may take place due to several possible mechanisms. The inverse variation of friction coefficient with relative sliding speed, also called negative μ-v slope, is one of them. Although it has been demonstrated in many articles that negative μ-v slope can cause unstable vibration for systems with a single degree of freedom (d.o.f.), its effects on multi-d.o.f. brake systems are not yet well understood. Since almost all types of friction materials for automotive brakes exhibit negative μ-v slope under certain conditions, it is important to clarify its role in brake squeal. The current study incorporates the negative μ-v slope friction law into a Finite element model for disc brake systems. The rotor and pads are modeled by beam elements, and the caliper is represented by a rigid body with two degrees of freedom. The effects of negative μ-v slope on the vibration stability of a brake system are studied along with several parameters including friction level, lining compression modulus, and steelback thickness.

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