Physical interpretations for cap parameters of the modified Drucker-Prager cap model in relation to the deviator stress curve of a particulate compact in conventional triaxial testing

2015 ◽  
Vol 280 ◽  
pp. 94-102 ◽  
Author(s):  
Hyunho Shin ◽  
Jong-Bong Kim
Keyword(s):  
Triaxial Testing ◽  
Deviator Stress ◽  
Stress Curve ◽  
Cap Model

Peak Undrained Resistance of Loose Sands

1997 ◽  
Vol 1569 (1) ◽  
pp. 65-76
Author(s):  
G. Norris ◽  
R. Madhu ◽  
M. Ashour ◽  
R. Valceschini
Keyword(s):  
Volumetric Strain ◽  
Confining Pressure ◽  
Triaxial Testing ◽  
Loose Sand ◽  
Failure Envelope ◽  
Change Measurement ◽  
Deviator Stress ◽  
Coulomb Failure ◽  
Volume Change Measurement ◽  
Liquefaction Analysis

The peak undrained resistance (σ d,upeak) of a loose sand during liquefaction under monotonic loading does not necessarily occur on or near the Mohr Coulomb failure envelope. Instead, it occurs as that combination or product of a decreasing effective confining pressure ([Formula: see text]) and an increasing stress level ( SL). The condition in which this product is a maximum occurs at a particular point on a plot of the deviator stress (σ d) versus volumetric strain (ε v) as assessed from a drained triaxial test. A method is presented whereby a single drained test with volume change measurement can be used to assess this undrained peak. This is a refinement of a more complete effective stress method of liquefaction analysis that requires only drained triaxial testing.

Post-liquefaction pore pressure dissipation in sand under cyclic stress triaxial testing

Géotechnique ◽  
2020 ◽  
Vol 70 (2) ◽  
pp. 95-107
Author(s):  
Saizhao Du ◽  
Siau Chen Chian ◽  
Changbing Qin
Keyword(s):  
Pore Pressure ◽  
Cyclic Stress ◽  
Triaxial Testing

scholarly journals Process Signature for Laser Hardening

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 465
Author(s):  
Friedhelm Frerichs ◽  
Yang Lu ◽  
Thomas Lübben ◽  
Tim Radel
Keyword(s):  
Residual Stress ◽  
Phase Transformation ◽  
Heating Time ◽  
Temperature Gradients ◽  
Laser Hardening ◽  
Thermal Loads ◽  
Zero Crossing ◽  
Residual Stress State ◽  
Stress Curve ◽  
Process Signature

During many manufacturing processes for surface treatment of steel components heat will be exchanged between the environment and the workpiece. The heat exchange commonly leads to temperature gradients within the surface near area of the workpiece, which involve mechanical strains inside the material. If the corresponding stresses exceed locally the yield strength of the material residual stresses can remain after the process. If the temperature increase is high enough additionally phase transformation to austenite occurs and may lead further on due to a fast cooling to the very hard phase martensite. This investigation focuses on the correlation between concrete thermal loads such as temperature and temperature gradients and resulting modifications such as changes of the residual stress, the microstructure, and the hardness respectively. Within this consideration the thermal loads are the causes of the modifications and will be called internal material loads. The correlations between the generated internal material loads and the material modifications will be called Process Signature. The idea is that Process Signatures provide the possibility to engineer the workpiece surface layer and its functional properties in a knowledge-based way. This contribution presents some Process Signature components for a thermally dominated process with phase transformation: laser hardening. The target quantities of the modifications are the change of the residual stress state at the surface and the position of the 1st zero-crossing of the residual stress curve. Based on Finite Element simulations the internal thermal loadings during laser hardening are considered. The investigations identify for the considered target quantities the maximal temperature, the maximal temperature gradient, and the heating time as important parameters of the thermal loads.

scholarly journals A spherical cap model of the geomagnetic field over southeast Asia from CHAMP and Swarm satellite observations

2021 ◽  
Vol 130 (1) ◽  
Author(s):  
Le Truong Thanh ◽  
Le Huy Minh ◽  
Vafi Doumbia ◽  
Christine Amory-Mazaudier ◽  
Nguyen Thanh Dung ◽  
...  
Keyword(s):  
Southeast Asia ◽  
Geomagnetic Field ◽  
Satellite Observations ◽  
Spherical Cap ◽  
Cap Model ◽  
Swarm Satellite

The Comparative Analysis of Cushion or Shock Absorption Characteristic of Commonly-Used Cushion Packaging Materials

2012 ◽  
Vol 490-495 ◽  
pp. 3902-3906 ◽  
Author(s):  
Zhen Jie Du ◽  
Wan Yu Gao ◽  
Hai Hong Kang ◽  
Sheng Jun Liu ◽  
Ming Xi Hu ◽  
...  
Keyword(s):  
Dynamic Compression ◽  
Static Stress ◽  
Final Conclusion ◽  
Absorption Characteristic ◽  
Packaging Materials ◽  
Shock Absorption ◽  
Static Test ◽  
Reference Information ◽  
Stress Curve ◽  
Packaging Structure

The purpose and method of this paper is to comparatively analyze several commonly-used cushion packaging materials, obtain their shock absorption characteristic curves, and by doing such, provide reference information for cushion packaging design and research. With the static test, dynamic compression test and vibration transfer test carried out, the cushion coefficient ~ static stress curve, maximal acceleration ~ static stress curve and vibration transfer rate ~ frequency curve are gained. A final conclusion is educed that in practical design routine, rational choice of cushion packaging materials, scientific design of packaging structure and validation of anti-vibration capability are relative to those three curves.

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