Seismic Reliability Investigation of Bearing Capacity of Foundations Based on Limit Analysis and Limit Equilibrium Metho
- PDF / 1,511,647 Bytes
- 14 Pages / 547.087 x 737.008 pts Page_size
- 114 Downloads / 187 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL PAPER
Seismic Reliability Investigation of Bearing Capacity of Foundations Based on Limit Analysis and Limit Equilibrium Methods Ali Shojaeian . Faradjollah Askari
Received: 25 June 2019 / Accepted: 26 June 2020 Springer Nature Switzerland AG 2020
Abstract In this paper, by considering the upperbound limit analysis method in calculating the seismic bearing capacity of foundations, the comparison between a limit equilibrium method such as Hansen and limit analysis method in terms of reliability is investigated. Limit equilibrium has been the oldest method for performing bearing capacity of foundations. However, it seems that theoretical equations proposed by the majority of old limit equilibrium methods to calculate the bearing capacity of foundations (such as Hansen) do not consider the effects of inertial forces of the earthquake in the soil mass. These methods only take into account the horizontal load applied to the foundation and disregard the earthquake forces applied to the soil. By comparing the results of this study, it can be inferred that the reliability of the Hansen approach is very close to the limit analysis method that ignores the impact of horizontal earthquake forces applied to rigid soil blocks. Since the upper-bound limit analysis takes into account the seismic effect of inertial forces in an earthquake, its results may be considered more accurate than Hansen. This study shows that in both granular and cohesive soils in high seismicity-prone areas, usage of a more A. Shojaeian F. Askari (&) Earthquake Engineering, International Institute of Seismology and Earthquake Engineering, Tehran, Iran e-mail: [email protected] A. Shojaeian e-mail: [email protected]
realistic method as the limit analysis is more reasonable. Considering the facility of RBD by Hansen method using EXCEL spreadsheet in comparison to the seismic reliability-based design using MATLAB programming following the upper-bound limit analysis method, graphs that offer coefficients for obtaining the equivalent value of target reliability in the limit analysis by using the Hansen formulation are presented. Additionally, this study shows that the horizontal seismic coefficient (kh) is an impressive parameter that affects the differences between the two mentioned approaches. Keywords Reliability-based analysis Seismic reliability Limit Analysis method Limit equilibrium method
1 Introduction Uncertainty as a general concept is a term that displays the uncertainty of a person about some phenomena. It includes the intervals between complete assurance and complete uncertainty. Uncertainty can be considered as a property of any system, representing the human knowledge deficiency about the parameters of the system. Reliability-based design methods are new approaches to quantitative uncertainties. In RBD, the distributions of variables are assigned to parameters instead of a particular value; hence, the distribution of
123
Geotech Geol Eng
the safety factor can be obta
Data Loading...
