New Approaches in Civil Engineering

New Approaches in Civil Engineering

Calculation of the Soil Spring Stiffness in Relation to the Structure’s Fundamental Period

Document Type : Original Article

Authors
Morvarid Hajian 1
Reza Attarnejad 2
1 Ph.D. Candidate of Structural Engineering, School of civil engineering, University of Tehran
2 Professor, School of civil engineering, university of Tehran
10.30469/jnace.2023.421381.1094
Abstract
In engineering design methods, it is assumed that the structure is located on a fixed base, and the effects of the soil environment on the structural response are generally ignored. However, research showed that the environment of the soil and the structure can interact with each other. This phenomenon is called soil-structure interaction effect. Therefore, the soil environment should be modeled in structural analysis. There are different methods for soil modeling. One of the practical methods is to use separate springs to model the soil environment. In this article, the effect of the number of floors and the period of the structure on the soil springs’ stiffness has been investigated. In this regard, three-dimensional structures with the number of floors 1, 3, 5 ,10 and 15 were modeled in Opensees software with continuous soil environment. Then, from the results of the structural analysis, the reaction of the soil under the foundation was calculated and relations were presented to determine the stiffness of the soil. These relationships are dependent on the structure’s period.
Keywords
Soil-structure interaction
Winkler model
elastic foundation
two-parameter foundation
period of structure
soil stiffness

Subjects

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New Approaches in Civil Engineering
Volume 7, Issue 4
Winter 2024
Pages 1-10