How does the absence and the presence of fluids in the rock affect its srength?

The presence of fluids in rocks can significantly reduce their strength by promoting processes like pore pressure development and weakening the bonding between mineral grains. Fluids can lead to the dissolution of minerals and enhance slip along existing fractures, making the rock more susceptible to deformation. Conversely, the absence of fluids typically results in higher strength due to increased friction and cohesion between the solid particles. In summary, fluid presence generally weakens rock, while its absence enhances structural integrity.