Final answer:
The high shear strength of quick clays can be dramatically reduced by adding salt, which causes the particles within the clay to flocculate and aggregate together, essentially neutralizing their charges.
Step-by-step explanation:
The relatively high shear strength of quick clays can be reduced to almost zero by adding salt to the particles causing them to flocculate together. This process is akin to the salting-out technique, where the addition of high amounts of salt leads to the formation of a precipitate by promoting particle-particle interactions over particle-water interactions. In the context of quick clays, the salt neutralizes the charged particles in the clay, encouraging aggregation and reducing the sheer strength significantly. Charge neutralization and the flocculation process are critical concepts in both natural and engineered environmental systems, as they affect the stability of soils and are utilized for treating water or wastewater.