The influence of the layered character of snow cover on the triggering of slab avalanches

One of the principal aims of avalanche warning is to prevent slab avalanches triggered by skiers. Other than explosives, the best practical tool for stability evaluation is the Rutschblock test. Whether the slab may be triggered by a skier depends on various slab characteristics. Important factors seem to be depth of the weak layer, slab hardness and sublayering of the slab. The stress distribution induced by a skier is calculated by the finite element method for typical snow-cover configurations. The additional shear stress is of the same order of magnitude as the shear strength of weak layers. Besides the critical weak layer — prerequisite for a slab avalanche — hard layers seem to be important. The analysis suggests that a shear failure is most probable at the transition from a hard to a soft layer. This corresponds well to observations of slab-avalanche profiles. The results may help to improve and quantify the analysis of snow profiles.

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Advanced Design of Block Shear Failure

Metals ◽

10.3390/met11071088 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1088

Author(s):

Marta Kuříková ◽

David Sekal ◽

František Wald ◽

Nadine Maier

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Shear Failure ◽

Plate Thickness ◽

Design Procedure ◽

The Finite Element Method ◽

Initial Stiffness ◽

Block Shear ◽

Internal Forces ◽

Element Method

This paper presents the behaviour and design procedure of bolted connections which tend to be sensitive to block shear failure. The finite element method is employed to examine the block shear failure. The research-oriented finite element method (RFEM) model is validated with the results of experimental tests. The validated model is used to verify the component-based FEM (CBFEM) model, which combines the analysis of internal forces by the finite element method and design of plates, bolts and welds by the component method (CM). The CBFEM model is verified by an analytical solution based on existing formulas. The method is developed for the design of generally loaded complicated joints, where the distribution of internal forces is complex. The resistance of the steel plates is controlled by limiting the plastic strain of plates and the strength of connectors, e.g., welds, bolts and anchor bolts. The design of plates at a post-critical stage is available to allow local buckling of slender plates. The prediction of the initial stiffness and the deformation capacity is included natively. Finally, a sensitivity study is prepared. The studied parameters include gusset plate thickness and pitch distance.

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Mechanics Research on the Vertical Bearing Characteristics of Suction Pile Cluster in Soft Ground

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.788.582 ◽

2013 ◽

Vol 788 ◽

pp. 582-585

Author(s):

Jin Qu ◽

David Du

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Shear Failure ◽

Tensile Failure ◽

Soft Ground ◽

Vertical Load ◽

The Finite Element Method ◽

Local Shear ◽

Vertical Bearing ◽

Pressure Suction

For a suction pile, drainage condition influences the magnitude of under-pressure ('suction'). As the growth of suction, the break-out resistance transforms from local shear failure, local tensile failure to general shear failure. This paper will discuss the failure mechanism of suction pile cluster under vertical load with different drainage conditions. The finite element method and software ABAQUS are employed to analysis these problems.

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Fast Computation of Microscale Temperature Distribution in LSI Chips

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47014 ◽

2003 ◽

Author(s):

Shigeki Hirasawa ◽

Satoru Isomura

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Temperature Distribution ◽

Silicon On Insulator ◽

Fast Computation ◽

The Finite Element Method ◽

Fast Calculation ◽

Temperature Distributions ◽

Network Method ◽

Practical Tool

A network method for quickly calculating the temperature distributions in an LSI chip with silicon-on-insulator (SOI) transistors and multi-layered lines has been developed. Its calculation time is less than 1/1000 of that of the finite element method, and its error is within 15%. The developed fast calculation method can be used in the case of more than 300 heating devices and more than 1000 lines in an LSI chip. It is thus a practical tool for designing the optimum layout of devices to prevent local temperature increases in an LSI chip.

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Calculation of Performance for Brushless Doubly-Fed Machine as Generator Based on Finite-Element Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.516-517.1584 ◽

2012 ◽

Vol 516-517 ◽

pp. 1584-1589

Author(s):

Yuan Cheng ◽

Xue Fan Wang

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Finite Element Model ◽

Element Model ◽

Analytic Method ◽

The Finite Element Method ◽

Order Of Magnitude ◽

Doubly Fed ◽

Doubly Fed Machine ◽

Element Method

For Brushless Doubly-fed Machine(BDFM), the main feature of field is that there are two kinds of magnetic fields differing in pole number in the machine’s iron circuit and the two fields have the same order of magnitude. Hence, it is difficult to calculate the machine’s performance accurately using conventional analytic method. In this paper, the author constructed one finite-element model of BDFM, and analyzed the machine’s performance using transient solver. The author also compared the finite-element method with experiment and conventional analytic method. Because taking into account the saturation, the results of finite-element method are closer to the measurements than that of conventional analytic method. The validity of model is verified.

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NUMERICAL PARAMETRIC STUDIES FOR THERMOGRAPHIC INSPECTION IN CONCRETE

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.148 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Rilya Rumbayan ◽

Glenn Washer

Keyword(s):

Finite Element Method ◽

Environmental Conditions ◽

Imaging Technique ◽

Direct Access ◽

The Finite Element Method ◽

Constant Multiple ◽

Thermal Contrast ◽

Thermographic Imaging ◽

Parametric Studies ◽

Practical Tool

Thermographic imaging technique provides a practical tool for the detection of subsurface delaminations in concrete from a distance without direct access to the surface. In the previous study, a numerical model to predict the thermal contrasts resulting from subsurface voids (i.e., delaminations) in concrete under a given set of environmental conditions was developed using the finite element method. The model was verified using the experimental test data, and the results indicated that the model could be an effective tool to support the thermography inspection of the concrete. In this present study, the use of the verified model to evaluate the effects of other key parameters expected to influence the detectability of the subsurface voids, such as the depth and thickness of a subsurface delamination. The effect of these parameters on the thermal contrast developed on the surface above a subsurface delamination was assessed under a specific set of environmental conditions. The results shown that the maximum thermal contrast decreased exponential by a constant multiple of 0.98 as the void depth increased and the maximum thermal contrast increased nonlinearly with increasing thickness of the void.

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Simulation of tuning graphene plasmonic behaviors by ferroelectric domains for self-driven infrared photodetector applications

Nanoscale ◽

10.1039/c9nr06508c ◽

2019 ◽

Vol 11 (43) ◽

pp. 20868-20875 ◽

Cited By ~ 1

Author(s):

Junxiong Guo ◽

Yu Liu ◽

Yuan Lin ◽

Yu Tian ◽

Jinxing Zhang ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Interfacial Effect ◽

Infrared Photodetector ◽

The Finite Element Method ◽

Ferroelectric Domains ◽

Element Method

We propose a graphene plasmonic infrared photodetector tuned by ferroelectric domains and investigate the interfacial effect using the finite element method.

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