Rock stresses and rock stress monitoring in Canada

AbstractA new simple mathematical method has been proposed to predict rock stress around a noncircular tunnel and the method is calibrated and validated with a numerical model. It can be found that the tunnel shapes and polar angles affect the applicable zone of the theoretical model significantly and the applicable zone of a rectangular tunnel was obtained using this method. The method can be used to predict the values of the concentrated stress, and to analyze the change rate of rock stress and back to calculate the mechanical boundary condition in the applicable zone. The results of the stress change rate indicate that the horizontal stress is negatively related to the vertical boundary load and positively related to the horizontal boundary load. The vertical stress is negatively related to the horizontal boundary load and positively related to the vertical boundary load. These findings can be used to explain the evolution of the vertical increment in stress obtained with field-based borehole stress monitoring.

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Influence of Sample Preparation on Intrinsic Stress Inside a Model Chip—Comparison of Results from Electric Read-Out and Raman Spectroscopy

ISTFA 2017: Conference Proceedings from the 43rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2017p0501 ◽

2017 ◽

Author(s):

T. Schaffus ◽

H. Pfaff ◽

P. Albert ◽

M. Schaffus ◽

F. Kroninger ◽

...

Keyword(s):

Raman Spectroscopy ◽

Sample Preparation ◽

Intrinsic Stress ◽

Stress Monitoring ◽

Preparation Methods ◽

Comparison Of Results ◽

The Given

Abstract The given project is to benchmark typical preparation methods under the aspect of the influence of initial intrinsic stresses inside electric components. Raman spectroscopy has been applied as well as the piezo resistive readout on a specifically designed model stress monitoring chip.

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Portable and wearable real-time stress monitoring: A critical review

Sensors and Actuators Reports ◽

10.1016/j.snr.2021.100036 ◽

2021 ◽

pp. 100036

Author(s):

Onur Parlak

Keyword(s):

Real Time ◽

Critical Review ◽

Stress Monitoring ◽

Time Stress

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Revisiting the concept of stress in forest trees at the time of global change and issues for stress monitoring

Plant Stress ◽

10.1016/j.stress.2021.100013 ◽

2021 ◽

pp. 100013

Author(s):

Filippo Bussotti ◽

Martina Pollastrini

Keyword(s):

Global Change ◽

Forest Trees ◽

Stress Monitoring

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Physics-Based Relationship for Pore Pressure and Vertical Stress Monitoring Using Seismic Velocity Variations

Remote Sensing ◽

10.3390/rs13142684 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2684

Author(s):

Eldert Fokker ◽

Elmer Ruigrok ◽

Rhys Hawkins ◽

Jeannot Trampert

Keyword(s):

Pore Pressure ◽

Seismic Velocity ◽

Pressure Head ◽

Groundwater Table ◽

Surface Velocity ◽

Seismic Velocities ◽

Stress Monitoring ◽

Near Surface ◽

Velocity Variations ◽

Velocity Changes

Previous studies examining the relationship between the groundwater table and seismic velocities have been guided by empirical relationships only. Here, we develop a physics-based model relating fluctuations in groundwater table and pore pressure with seismic velocity variations through changes in effective stress. This model justifies the use of seismic velocity variations for monitoring of the pore pressure. Using a subset of the Groningen seismic network, near-surface velocity changes are estimated over a four-year period, using passive image interferometry. The same velocity changes are predicted by applying the newly derived theory to pressure-head recordings. It is demonstrated that the theory provides a close match of the observed seismic velocity changes.

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A Review of Biophysiological and Biochemical Indicators of Stress for Connected and Preventive Healthcare

Diagnostics ◽

10.3390/diagnostics11030556 ◽

2021 ◽

Vol 11 (3) ◽

pp. 556

Author(s):

Talha Iqbal ◽

Adnan Elahi ◽

Pau Redon ◽

Patricia Vazquez ◽

William Wijns ◽

...

Keyword(s):

Cardiovascular Events ◽

Medical Conditions ◽

Review Of The Literature ◽

Stress Monitoring ◽

Preventive Healthcare ◽

Connected Health ◽

Root Cause ◽

Chemical Indicators ◽

Life Threatening ◽

Assessment Of Stress

Stress is a known contributor to several life-threatening medical conditions and a risk factor for triggering acute cardiovascular events, as well as a root cause of several social problems. The burden of stress is increasing globally and, with that, is the interest in developing effective stress-monitoring solutions for preventive and connected health, particularly with the help of wearable sensing technologies. The recent development of miniaturized and flexible biosensors has enabled the development of connected wearable solutions to monitor stress and intervene in time to prevent the progression of stress-induced medical conditions. This paper presents a review of the literature on different physiological and chemical indicators of stress, which are commonly used for quantitative assessment of stress, and the associated sensing technologies.

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