A Structural Design Comparison Between Two Reinforced Concrete Regular 6-Level Buildings using Soil-Structure Interaction in Linear Range

Nelson Andrés López Machado,Juan Carlos Vielma Perez,Vanessa Viviana Montesinos Machado,David Patricio Guerrero Cuasapaz,Leonardo José López Machado,José Domingo Alviar Malabet,Christian Castro,Carlos Alberto Romero Romero,Gabriela Perez

doi:10.15446/ing.investig.v42n1.86819

Abstract

Structural engineers commonly design superstructures as fixed at the base and transmit the reactions to the infrastructure in order to design the foundation system and estimate the displacement of the soil while disregarding the change in seismic response that this induces. In this article, the foundation system was transformed into equivalent springs, and the seismic response in the linear range was compared and quantified, obtaining results such as increased periods, increased amounts of steel reinforcement in beams (between 7% and 25%) and columns (between 29% and 39%), an increase in the number of stirrups per linear meter (between 3% and 11% in columns and between 5% and 45% in beams) and drifts (between 1% and 14%), and a decrease in basal shear (up to 20%), which directly affects the design of the structure. This study concludes that the inclusion of the soil-structure interaction is necessary for structural design in the linear range.

Highlights

Structural engineering always aims for the best way to represent a real structure in a mathematical model in order to obtain the best approach to the reality
To represent soil and substructure displacements, it is necessary to calculate the foundation system, in order to substitute it with equivalent springs using the concepts of rotational and translational stiffness (UribeEscamilla, 2000; Weaver and Gere, 1990; López et al, 2019), which express that a structural element can be represented through its rotational and translational stiffness coefficients, as shown in Equations (1) and (2)
F = KRθ where F is the force applied on a structural element; KT is the element’s translational stiffness constant; d is the displacement in the force’s direction; M is the torsional or bending moment applied on the structural element; KR is the element’s rotational stiffness constant; and θ is the rotation in the moment’s direction

Summary

Introduction

Structural engineering always aims for the best way to represent a real structure in a mathematical model in order to obtain the best approach to the reality. To represent soil and substructure displacements, it is necessary to calculate the foundation system, in order to substitute it with equivalent springs using the concepts of rotational and translational stiffness (UribeEscamilla, 2000; Weaver and Gere, 1990; López et al, 2019), which express that a structural element can be represented through its rotational and translational stiffness coefficients, as shown in Equations (1) and (2). To make soil-structure interaction possible, it is necessary to obtain the values of F, d, M, and θ.

Objectives

Methods

Findings

Discussion

Conclusion