Fast fragility analysis of plan-asymmetric structures considering soil-structure interaction using flexible base 2 degrees of freedom Modal Pushover Analysis (F2MPA)

2020 ◽  
Vol 138 ◽  
pp. 106270
Author(s):  
Mohammad S. Birzhandi ◽  
Amir M. Halabian
2020 ◽  
Vol 8 ◽  
pp. 22-29
Author(s):  
Nasala Dongol ◽  
Prachand Man Pradhan ◽  
Suman Manandhar

This study states that the effects of soil structure interaction on the Reinforced Concrete (RC) framed structures is directly influenced by the soil properties of the site. Here, one preexisting structure is taken for the study. The building is a hospital building with two underground basements. Taking into account the actual soil condition of building site, this study provides idea on the soil structure interaction on the structure The properties of springs are calculated from different standard penetration test (SPT) values, Poisson’s ratio and elasticity of soil along the depth of the soil. Entire soil-foundation-structure system is modelled and analyzed using spring approach. Static analysis, response spectrum analysis and pushover analysis (PA) are done in order to find the variations in natural periods, base shears and deflections of the structures by incorporating soil flexibility as compared to structures with conventional fixed base. Pushover analysis is done to evaluate the performance of the structure when modelled in fixed base and spring base system.


2017 ◽  
Vol 20 (11) ◽  
pp. 1712-1726
Author(s):  
Farhad Behnamfar ◽  
Seyyed Mohammad Mirhosseini ◽  
Hossein Alibabaei

A common assumption when analyzing a structure for earthquake forces is that the building is positively attached to a rigid ground so that it can sustain possible tensile forces without being detached, or uplifted, from its bearing points. Considering the facts that almost no tension can be transferred between a surface foundation and soil and soft soils interact with the supported structure during earthquakes, in this research, the effects of uplift and soil–structure interaction on nonlinear seismic response of structures are evaluated. Several reinforced concrete and steel structures under different suits of consistent ground motions are considered. The base of the buildings is modeled with vertical no-tension springs being nonlinear in compression. The total soil–structure interaction system is modeled within OpenSees, and the seismic behavior is evaluated using a nonlinear dynamic analysis. The nonlinear responses of buildings are determined and compared between three cases: fixed base, flexible base without uplift, and flexible base with uplift. The cases for which uplift in conjunction with soil–structure interaction should be considered are identified.


Sign in / Sign up

Export Citation Format

Share Document