Question

5. Describe why kinematic soil-structure interaction is extremely important while inertial SSI is not important for buried structures such as tunnels and pipelines

Answer 1

Answer:

When the SSI effect is related to the structural stiffness then it is called kinematic interaction. While on the other hand when it is related to the mass of the structure then it is called inertial SSI.The inertial SSI is a result of seismic inertial forces, which is caused by the product of mass and the direction of acceleration of the earthquake. The resulting dynamic force does not however occur for fixed base structures.

Kinematic interaction is affected by the geometry and orientation of the structure, foundation embedment,etc So for tunnels and pipelines it cannot be ignored Along side, the dissipation capability is also less. The inertial structure is not significant for structures founded on stiff soil or rock,inertial interaction develops in a structure due to its self- vibration, whereas for kinematic vibration, the presence of stiff foundation elements or motions is important.