Total stress represents the total force acting on a unit area of a material, encompassing all forces present. This definition applies across various disciplines, and its specific meaning depends on the context. Let's examine total stress in different fields:
Total Stress in Geotechnical Engineering
In geotechnical engineering, total stress at a point is the sum of the stress exerted by the total weight (solids plus water) of the soil/rock and any external load on top (e.g., a foundation). [Encyclopedia of Physical Science and Technology (Third Edition), 2003]. This is crucial for understanding soil behavior and stability.
- At a given layer: Total stress equals the weight of everything above that layer per unit area [apsed.in]. This includes the weight of the soil, water, and any surface loads.
- Relationship with effective stress: Total stress is related to effective stress and pore water pressure. Effective stress is the part of the total stress carried by the soil skeleton (the solid particles), while pore water pressure is the stress carried by the water within the soil pores. Mathematically, effective stress = total stress - pore water pressure [sciencedirect.com].
- Limitations of testing: While methods exist to determine total stress parameters, some standard tests, like CU triaxial tests, aren't designed to directly measure total stress strength envelopes [eng-tips.com].
Total Stress in Other Fields
Beyond geotechnical engineering, "total stress" has different meanings:
- Thermoelasticity: In this context, total stress is the mechanical stress minus the thermal stress [physics.stackexchange.com].
- Physiology (Training Stress Score): In sports science, total stress refers to the overall training load and physiological strain from a workout session, often measured using metrics like Training Stress Scores (TSS) [trainingpeaks.com].
- Medicine (Lung Stress): Total lung stress refers to the overall pressure on the lungs, relevant in understanding respiratory conditions like COVID-19 [pubmed.ncbi.nlm.nih.gov].
Understanding total stress requires careful consideration of the specific field and its related definitions and calculations.
