Huerta, Juan Enrique

Inelastic Behavior of RC Building Considering Dynamic Soil-Structure Interaction

Abstract eng:
Analysis of buildings under seismic actions with flexible base must consider two principal components in the structure displacement, one introduced by structural deformation and the other due to a rigid body behavior. This effect produces that the relation between ductility demand and inelastic capacity of the structure is modified. In addition, consideration of flexible base may change the distribution of internal forces along the structure that could generate variations on the ductility demands over different structural elements. This work explores the behavior of a 10-story regular building with RC moment resisting frames considering the dynamic soil structure interaction. The response of the building with flexible base is compared and contrasted with the rigid base case. The inelastic behavior of the buildings is characterized in terms of ductility capacity and demands. Pushover analysis is used to establish the inelastic capacity parameters. Capacity curves of the building with rigid (fixed) and flexible base are studied. In addition, the comparison of ductility demands is presented. Ductility demands are computed with non linear time history dynamic analysis. Accelerograms used as excitation are scaled to meet design spectral acceleration. Soil-foundation dynamic stiffness (impedance functions) is introduced in the analysis by using a set of springs in horizontal and rocking direction. A mat foundation is considered. A very soft soil with shear wave velocity of Vs=100 m/s is used. Springs stiffness are computed considering the dynamic behavior and properties of the soil-foundation system with a commercial software. Results show that ductility capacity of the soil-structure system is reduced if rigid body displacement components are not eliminated. On the other hand, ductility demands and hysteretic behavior of the global system and local elements are modified due to base flexibility. Some elements experience reduced hysteretic loops when flexible base is considered. Base flexibility produces changes in the relation between yield strength reduction factor and structure ductility demand.

Contributors:

Fernandez-Sola, Luciano Roberto

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

Text je chráněný podle autorského zákona č. 121/2000 Sb.