What is the maximum vertical pressure that causes a shear failure mechanism?

The maximum vertical pressure that causes a shear failure mechanism is known as the Ultimate Bearing Capacity. This term refers to the maximum load per unit area that the soil can withstand before failure occurs, taking into consideration the material's shear strength.

In geotechnical engineering, understanding the ultimate bearing capacity is crucial for designing foundations, as it helps engineers ensure that the load applied by the structure does not exceed what the soil can safely bear. When the vertical pressure surpasses this limit, the soil may fail by shear, leading to potential structural problems or even collapse.

The other terms mentioned, while related to load capacities, do not represent the threshold at which shear failure occurs. For instance, Allowable Bearing Capacity generally reflects a value that incorporates safety factors, ensuring that the actual loads experienced are within safe limits, while Safe Load Capacity often denotes the maximum load that a structure can support during its operational lifespan, considering several safety factors. Standard Load Capacity tends to represent a commonly accepted load value for design purposes but does not specifically indicate a failure threshold.