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Program 3D-BASIS-ME-MB is a computer program for the dynamic response-history
analysis of seismically isolated structures. The new program offers the following
improvements over its predecessor: capability to analyze multiple superstructures on
multiple isolation-system levels; (b) addition of a new element for modeling the upliftrestraining
XY-FP...
Citations
... The FPS consists of a spherical concavity and a slider that slides on the spherical surface to impart the slide-type bearing with restoring-force action and frictional energy dissipation capacity. Numerous experimental and analytical studies (Mokha, Michalakis, and Andrei 1990;Mosqueda, Whittaker, and Fenves 2004) were first conducted to confirm the performance of this bearing under various conditions, and analytical models (Constantinou, Mokha, and Reinhorn 1990;Nagarajaiah, Constantinou, and Reinhorn 1989;Tsopelas, Michalakis, and Andrei 1994;Wang, Loi Chung, and Hsin Liao 1999) were subsequently developed to accurately solve the nonlinear dynamic response of structures equipped with this bearing. The effectiveness of the FPS in bridge structures has also been comprehensively investigated (Constantinou, Mokha, and Reinhorn 1990;Dicleli and Mansour 2003;DesRoches 2008, 2013;Nagarajaiah, Reinhorn, and Constantinou 1991). ...
... Researchers have investigated the friction model in FPSs under various conditions. Constantinou et al. experimentally investigated the friction of the sheet -type Teflonsteel interfaces used in FPS through a series of velocity -controlled and pressure -controlled laboratory tests and proposed a mathematical model to consider the effects of velocity and pressure dependences, the breakaway motion, and the multidirectional motion (Constantinou et al. 1999;Constantinou, Mokha, and Reinhorn 1990;Tsopelas, Michalakis, and Andrei 1994). A friction coefficient model that accounts for the breakaway effect at the beginning of the sliding motion has also been proposed (Gandelli and Quaglini 2020;Quaglini et al. 2019). ...
Although the friction pendulum bearing system (FPS) has been widely used in the construction of buildings, bridges, and other structures to enhance their seismic performance, the FPS was adopted in bridge construction in Japan for the first time in 2020 on the Tokai-Hokuriku expressway. To validate the design hypotheses of the real bridge with FPS, a series of static and dynamic tests were performed, and the parameters of the FPSs were estimated. The girder of the bridge supported by four FPSs was pushed to various specified displacements considered in a maximum considered earthquake event in a quasi-static manner by hydraulic jacks equipped with large-caliber valves to enable quick pressure release. The load of the jacks was then suddenly released so that the bridge entered free vibration. The bearings in the site static tests are found to undergo a noncontinuous sliding motion (stick-slip) because a small loading rate of jacks is applied. This stick-slip phenomenon is confirmed in both the site and laboratory tests in cases where the sliding velocity either approached 0 or departed from 0, i.e. at every velocity reversal. The friction coefficient is estimated from the force and displacement data at the sliding points, and good agreement is observed between the site static tests and the laboratory tests. The friction coefficient model for dynamic analysis, accounting for the stick-slip effect and several dependencies, is calibrated by these test results. The free-vibration test results, including measured displacements and accelerations, show agreement with the simulation results based on a simplified model of the bridge with the FPSs. Finally, the unscented Kalman filter and its adaptive variant are applied to estimate the design parameters of the FPSs.
... However, analysis results may lead to the underestimation of displacement demands by omitting the coupled plasticity models. In structural analysis programs like SAP2000 [24], 3D-BASIS-ME-MB [25] two-directional smooth bilinear hysteretic models are established utilizing the approach of Park et al. [26]. Smooth bilinear hysteretic models give acceptable results under bi-directional input motions [25]. ...
... In structural analysis programs like SAP2000 [24], 3D-BASIS-ME-MB [25] two-directional smooth bilinear hysteretic models are established utilizing the approach of Park et al. [26]. Smooth bilinear hysteretic models give acceptable results under bi-directional input motions [25]. The forces mobilized in the orthogonal directions during earthquake excitation can be defined by Equations (6) and (7). ...
... The earlier analytical models used for elastomeric bearings are based on the non-degrading and unidirectional tools, where the bidirectional effects are calculated using the weighted vector sum at each direction. In the intervening years, research studies have highlighted the importance of considering multidirectional loading properly where coupled plasticity models and smooth plasticity models are integrated into commercial software and object-oriented software with success [24,25]. Mathematical models using idealized bilinear load-deformation relationships in the commercial software only capture the well-established overall response in shear and compression. ...
Earthquake Seismic isolation plays an important role in achieving sustainable earthquake resilience communities. Seismic isolation method is a justified, mature, and reliable performance enhancement strategy for a wide range of structural systems and valuable contents. As a result of the targeted response modification, high-performance expectations and earthquake resilience can be achieved during the service life of the structures that are compliant with the design code requirements. Design and analysis procedures of isolation systems in standards were evolved substantially to expand the use of isolation technology and quantify the benefits of isolation systems to overcome the existing impediments. Strictly speaking, new tools are offered to the engineering community to highlight the possible issues that may appear in isolation units beyond the design basis earthquake level to improve the accuracy of response prediction. This paper aims to overview the characteristics of frequently used isolation systems in the industry with mathematical models, design criteria toward sustainable communities, the current state of practice along with the set forth design requirements of selectively well-known standards with special emphasis to the ELF procedure from the perspective of performance-based design philosophy. Additionally, two large-scale seismic isolation applications in the world are given as benchmark studies for the new construction and upgrading scheme in the content of the study.
... Several hysteretic models have been proposed in the literature for simulating the complex behavior occurring in sliding bearings [9]. Among existing models, the one proposed by Mokha et al. [10] seems to be the most suitable one since it allows for an accurate prediction of the hysteretic response of both flat and curved surface sliding bearings by using a relatively small number of parameters. ...
... In commercial software programs for structural analysis, the force-displacement behavior of sliding isolators has been repro- duced by means of either a coupled plasticity model [Simo and Hughes, 1998], where the plastic deformation corresponds to the displacement occurring during the accommodated sliding motion and the elastic deformation to the deformation in shear of the sliding material, or a generalized Bouc-Wen smoothed plasticity model [Park et al., 1986], whose parameters satisfy an evolutionary differential equation, extended to seismic isolation bearings by Nagarajaiah et al. [1991]. The coupled plasticity model is used in OpenSees (Open System for Earthquake Engineering Simulation) [Mosqueda et al., 2004b], whereas the generalized Bouc-Wen model is implemented in SAP 2000 [Computer and Structures, 1997], MIDAS GEN [Midas, 2008], and 3-D BASIS [Tsopelas et al., 1994[Tsopelas et al., , 2005. ...
Effective implementation of the static friction of sliding isolators in object-oriented software for structural design has not yet been achieved, and use of the dynamic friction only for design is common practice. A modeling strategy to account for the contribution of static friction under unidirectional ground motion histories has been developed and used to assess its effects on the response of a building isolated with curved surface sliders. Under low-to-moderate intensity earthquakes , disregarding static friction can lead to unpredictable response of the isolation system and result in a non-conservative evaluation of accelerations and forces transferred to the superstructure.
... For the solution of these equations, the unconditionally Newmark's constant-average-acceleration method is applied, Tsopelas (2005). The total horizontal base shear is calculated as a result of time history analyses which is also given by Jadhav and Jangid [12]: ...
... The resisting force (F) in global axes x and y, produced by the isolator is provided by [24] as: ...
... The normal load on the bearing is given by Tsopelas et al. [24] as; ...
In this paper, the seismic response of base-isolated liquid storage tanks subjected to real and simulated near-fault ground motions is investigated. It is assumed that the tanks are seismically isolated by single surface Concave Sliding Bearings (CSB) with different isolation periods. For the input data, the recorded and simulated ground motions having pulse type characters and their dominant waveforms are considered. For each case considered, numerical analyses are carried out to calculate the critical demand parameters such as base shear values, bearing and sloshing displacements of the tank. The results revealed that, the base shear response of the slender tank to real and simulated ground motions and equivalent pulses tend to approach each other at isolation periods around 3 s and then remain constant in higher periods. Similar findings are not observed for the broad tank. Depending on the special case considered in this study, it can be said that, for the preliminary design of slender tanks in the near-fault regions, the real earthquakes can be replaced by equivalent pulses especially for isolation periods larger than 3s.
... Various structural analysis programs in practice are available for the capturing the overall behavior of the seismically isolated buildings (e.g. [16,61]). In the scope of this study, SAP2000 Version 14.2.2 [16] is assumed to be suitable for performing the structural analyses due to its wide Implicit in the definition of MCE level **xi,yi¼ coordinates of the isolator unit i relative to the effective stiffness center. ...
Seismic isolation method is an innovative mature performance enhancement strategy to mitigate the earthquake risk on structures. As a result of the targeted response modification, feasible engineering solutions can be achieved during the service life of structures. For both bridges and buildings simplified analysis procedure of seismic isolation systems are set forth in guide specifications and design provisions. Equivalent lateral force (ELF) method in buildings can be considered as the simplest method of analysis with high importance. This procedure can be directly used in the analysis and design of seismically isolated structures or it can be used in the establishment of lower-bound limits to nonlinear time history analysis. This paper focuses on the overview of design procedures of isolated buildings and comparison of the analysis results of ELF procedure based on selectively well-known codes and guidelines used in pioneering countries. The buildings were equipped with two commonly used isolation systems named as lead rubber bearing and curved surface friction sliders. A comparison of the 2016 Edition of the Turkish Seismic Design Code with the US(ASCE/SEI 7–10), the European (Italian version of the Eurocode (EC-8) application, NTC-08) and the Japanese (Building Standard Law-2013) codes is conducted on the implementation of the ELF Method for parametric study of structures located at sites of similar probabilistic earthquake hazard in respective countries. Recommendations and concerns associated with the current-state of practice and ongoing development new reference section of TSDC are highlighted by comparing code compliance approaches and practical applications.
... 3D-BASIS-M and 3D-BASIS-ME offer the advantage of analyzing multiple buildings on a common isolation basemat, with the isolation system below, while only a single building on isolation system can be analyzed using 3D-BASIS and 3D-BASIS-TABS. Most recent in the series is 3D-BASIS-ME-MB, which includes the capability of model uplift [38]. 3D-BASIS class of programs are distributed through the Multidisciplinary Center for Earthquake Engineering, Buffalo, and National Information Service for Earthquake Engineering, University of California, Berkeley. ...
Origins and development of 3D-BASIS (3-Dimensional BASe Isolated Structures) was initially envisioned by the need for an efficient tool for nonlinear dynamic analysis of three-dimensional base isolated structures, particularly in solving the highly nonlinear bidirectional stick-slip hysteretic response of a collection of sliding isolation bearings and the resulting response of the superstructure, as this was not available at that time. The primary challenge was to solve the stick-slip behavior of friction bearings—modeled using a differential equation (Bouc-Wen Model) due to its efficiency in representing constant Coulomb friction or variable velocity depended friction by using a very small yield displacement during the stick phase resulting in very high tangential stiffness followed by a very small tangential stiffness during the sliding phase—and the resulting stiff differential equations. A challenge that is compounded when biaxial-friction is modeled, wherein even the traditional method of using Gear’s method to solve stiff differential equations breaks down—a problem that was vexing the research team at University at Buffalo trying to solve the problem at that time. The answer was the development of the novel pseudo-force solution algorithm along with a semi-implicit Runge-Kutta method to solve the difficult problem. The efficient solution procedure is needed primarily for the nonlinear isolation system consisting of (1) sliding and/or elastomeric bearings, (2) fluid dampers, (3) other energy dissipation devices, while the superstructure is represented by three dimensional superstructure model appropriately condensed (where only master nodes at the center of mass of the floor are retained). This chapter describes the origins, development of 3D-BASIS and its impact.
... In order to analyze the structural models, 3D-BASIS-ME-MB that is a computer program for nonlinear dynamic analysis of seismically isolated structures, was used [15,16]. Structural models prepared for analysis include 15-story buildings. ...
... Note that Equation (19) must be used to update the force vector of an SFP bearing for a given incremental displacement vector, particularly when a variation of the vertical force is expected. If the stiffness of the SFP is required to be found, the same equation should be formulated by adding [k h ] and [k e ] algebraically after updating each of the stiffness matrices using the current forces and displacements of the SFP. ...
... r mul is taken as 1.0 for both isolators. For variable vertical load, the 'T-matrix' and 'A-matrix' (refer to Tsopelas, et al. [19]) required in 3DBASIS were formulated using SAP2000 (Computers and Structures Inc., 1646 N. California Blvd., Suite 600 Walnut Creek, CA 94596, USA) analysis. The ground motions used in the analysis were those recorded from the shake table test. ...
The friction pendulum system is a sliding seismic isolator with self‐centering capabilities. Under severe earthquakes, the movement may be excessive enough to cause the pendulum to hit the side rim of the isolator, which is provided to restrain the sliding. The biaxial behavior of a single friction pendulum, in which the slider contacts the restrainer, is developed using a smooth hysteretic model with nonlinear kinematic hardening. This model is extended to simulate the biaxial response of double and triple friction pendulums with multiple sliding surfaces. The model of a triple friction pendulum is based on the interaction between four sliding interfaces, which in turn is dependent upon the force and displacement conditions prevailing at these interfaces. Each of these surfaces are modeled as nonlinear biaxial springs suitable for a single friction pendulum, using the yield surface, based on the principles of the classical theory of plasticity, and amended for varying frictional yield force, due to variation in vertical load and/or velocity‐dependent friction coefficient. The participation of the nonlinear springs is governed by stick‐slip conditions, dictated by equilibrium and kinematics. The model can simulate the overall force‐deformation behavior, track the displacements in individual sliding surfaces, and account for the ultimate condition when the sliders are in contact with their restrainers. The results of this model are verified by comparison to theoretical calculations and to experiments. The model has been implemented in programs IDARC2D and 3D‐BASIS, and the analytical results are compared with shake table experimental results. Copyright © 2013 John Wiley & Sons, Ltd.
... Fig. 2 shows an idealized forcedisplacement loop of a traditional FPS bearing. The model is characterized by six parameters, namely, the radius of bearing f , min f and a have been reported [16]. ...
In recent years using of base isolation systems due to improve in seismic performance of liquid storage tank was expanded. In this paper, the seismic behavior of the Liquid storage tank supported on DCFP isolation system under seven ground motions was investigated. The effects of essential parameters including slender of tank, period and coefficient of friction of the isolation system were investigated. In the parametric study, mass of liquid was idealized as convective mass, impulsive mass and rigid mass. In this analysis simplified three-degree freedom model to represent flexural and rocking vibrations of the tank was used. The results represent increasing of the slender ratio increases base shear and isolators forces and affects slightly on drift and isolation displacement. It is also shown that the period of isolators affects significantly on relative displacement of convective mass and isolators are remarkable.
