Dynamic analysis of fiber-reinforced elastomeric isolation structures

Abstract

This paper presents an analysis of seismically isolated buildings using fiber-reinforced elastomeric structures that are subject to excitations caused by earthquakes. In analyzing the vibrations, the buildings are modeled by lumped mass systems. The fundamental equations of motion are derived for base isolated structures, and the hysteretic and nonlinear-elastic characteristics are included in the numerical calculations. The earthquake waves used as the excitation forces are those that have been recorded during strong earthquake motions in order to examine the dynamic stability of building structures. The seismic (nonlinear) responses of the building are compared for each restoring force type and, as a result, it is shown that the building's motions are not so large from a seismic design standpoint. Isolating structures are shown to reduce the responses sufficiently allowing the building's motions to be controlled to within a practical range. By increasing the acceleration of the earthquake, the yielding forces in the concrete and steel frames can be determined, which shows the advantages of performing nonlinear dynamic analysis in such applications.

Dynamic response characteristics of seismic isolation systems for building structures

“…To solve these disadvantages of the SREI isolation system, the fiber-reinforced elastomeric isolator (FREI) has been introduced and examined analytically for its compression stiffness. Additionally, a comparative study on the effects of the mechanical properties for the FREI with a hole and lead plug effects was also carried out [6][7][8][9].…”

Review: Design of Passive Composite Isolation System for Machine Foundaion

“…GyungJu Kang [2] investigates Dynamic analysis of fiber-reinforced elastomeric isolation structures (2009). This work is related with analysis of seismically isolated buildings using fiber-reinforced elastomeric structures that are subject to excitations caused by earthquakes.…”

“…This is achieved by installing isolators which have low horizontal, but high vertical and bending stiffness beneath superstructure [5]. Vibration isolation is the action or treatment that eliminates the unwanted vibration or reduces it to an acceptable level [2]. Composite polymers have been used as isolators for their damping ability.…”

“…Thus, a key ingredient to a successful machine foundation design is the careful engineering analysis of the foundation response to the dynamic loads from the anticipated operation of the machine [15].. Volume 4, Issue 5, May-2017, e-ISSN: 2348-4470, print-ISSN: 2348 As the area of working is very critical, so as per that case design of machine foundation is very important, in which vibrations are taken into account, the following conditions should be satisfied by isolating pads [10]:…”

Analytical vs Numerical Determination of the Axial and Lateral Stiffness of Fiber Reinforced Isolators

“…The fiber-reinforced elastomeric isolators (FREIs) have been developed in the last years as alternative to the conventional steel reinforced elastomeric isolators (SREIs) [1] in the attempt of reducing the weight, manufacturing time and cost of rubber based devices [2]- [4], and with this to permit their application to all type of structures, including low-cost residential buildings.The main characteristics of the FREIs are: traditional steel plates are replaced with fabric reinforcement layers of different kind [5]- [9]; and the bearings are not bonded to the structure. This latter feature together with the lack of flexural rigidity of the fiber-reinforcements allow the bearings to roll-of the supports when deformed in shear, eliminating the high tensile stresses developed in a bonded isolator when it is displaced horizontally [10], [11].…”