Floor Accelerations in Yielding Special Moment Resisting Frame Structures

2013 ◽  
Vol 29 (3) ◽  
pp. 987-1002 ◽  
Author(s):  
Joseph Wieser ◽  
Gokhan Pekcan ◽  
Arash E. Zaghi ◽  
Ahmad Itani ◽  
Manos Maragakis
Keyword(s):  
Three Dimensional ◽  
Response Spectra ◽  
Ground Acceleration ◽  
Nonstructural Components ◽  
Moment Resisting Frame ◽  
Floor Slabs ◽  
Moment Resisting ◽  
Special Moment Resisting Frame ◽  
Recent Earthquakes ◽  
Floor Acceleration

Severe damage to acceleration sensitive nonstructural components in recent earthquakes has resulted in unprecedented losses. Recent research has been aimed at increasing the understanding of acceleration demands on nonstructural components in buildings. This investigation subjects a set of four special moment resisting frame (SMRF) building models to a suite of 21 far-field ground motions using the incremental dynamic analysis procedure. Full three-dimensional models including floor slabs are used to extract both the horizontal and vertical responses. Floor acceleration response spectra are generated to assess the acceleration demands on elastic nonstructural components. Changes to the current code provisions that include the influence of structural period are proposed. An alternative design approach that directly amplifies the ground acceleration spectrum to achieve the desired floor acceleration spectrum is presented.

Evaluation of floor acceleration demands from the 2017 Mexico City code seismic provisions using a continuous elastic model and records of instrumented buildings

2020 ◽  
Vol 36 (2_suppl) ◽  
pp. 213-237
Author(s):  
Miguel A Jaimes ◽  
Adrián D García-Soto
Keyword(s):  
Mexico City ◽  
Seismic Design ◽  
Soft Soil ◽  
Response Spectra ◽  
Elastic Model ◽  
Ground Acceleration ◽  
Nonstructural Components ◽  
Floor Response Spectra ◽  
Instrumented Buildings ◽  
Floor Acceleration

This study presents an evaluation of floor acceleration demands for the design of rigid and flexible acceleration-sensitive nonstructural components in buildings, calculated using the most recent Mexico City seismic design provisions, released in 2017. This evaluation includes two approaches: (1) a simplified continuous elastic model and (2) using recordings from 10 instrumented buildings located in Mexico City. The study found that peak floor elastic acceleration demands imposed on rigid nonstructural components into buildings situated in Mexico City might reach values of 4.8 and 6.4 times the peak ground acceleration at rock and soft sites, respectively. The peak elastic acceleration demands imposed on flexible nonstructural components in all floors, estimated using floor response spectra, might be four times larger than the maximum acceleration of the floor at the point of support of the component for buildings located in rock and soft soil. Comparison of results from the two approaches with the current seismic design provisions revealed that the peak acceleration demands and floor response spectra computed with the current 2017 Mexico City seismic design provisions are, in general, adequate.

A comparative study of floor accelerations of different structural systems with lead-rubber-bearing (LRB) isolators

2020 ◽  
Author(s):  
Ali Ruzi Özuygur
Keyword(s):  
Base Isolation ◽  
Damping Ratio ◽  
Dual System ◽  
Base Shear ◽  
Nonstructural Components ◽  
Moment Resisting Frame ◽  
Lead Rubber Bearing ◽  
Moment Resisting ◽  
Seismic Base Isolation ◽  
Floor Acceleration

Seismic base isolation has been successfully used to protect structural and nonstructural components from the damaging effects of earthquakes by reducing floor accelerations and inter-story drifts for decades. The level of floor acceleration is a key issue in the protection of acceleration-sensitive nonstructural components. In this paper, floor acceleration performance of seismically isolated buildings with different lateral load resisting systems such as moment resisting frame, dual system, moment resisting frame plus viscous wall dampers and dual system plus viscous wall dampers is investigated. Moreover, the effectiveness of supplemental viscous damping devices equipped in parallel with lead-rubber isolators is studied. It is inferred from the study that the most effective way of reducing floor accelerations is to provide more rigidity to the superstructure. Utilizing supplemental viscous dampers along with lead-rubber isolators having about 20% of effective damping ratio is meaningless or harmful in relation to floor acceleration and base shear.

Evaluation of the seismic level of protection afforded to steel moment resisting frame structures designed for different design philosophies

1999 ◽  
Vol 26 (1) ◽  
pp. 35-54 ◽  
Author(s):  
Aiman Biddah ◽  
Arthur C Heidebrecht
Keyword(s):  
Collapse Mechanism ◽  
Steel Moment Resisting Frames ◽  
Design Philosophy ◽  
Moment Resisting Frame ◽  
Panel Zone ◽  
Statistical Measures ◽  
Frame Buildings ◽  
Moment Resisting ◽  
Steel Moment Resisting Frame ◽  
Recent Earthquakes

Steel moment resisting frames have been considered as excellent systems for resisting seismic loads. However, after recent earthquakes (e.g., Northridge, California, in 1994 and Kobe, Japan, in 1995) the confidence in this structural system was reduced as a result of various types of damage that moment resisting steel frames suffered. This paper presents the results of the evaluation of seismic level of protection afforded to steel moment resisting frame buildings designed in accordance with the National Building Code of Canada. Six- and 10-storey office buildings located in a region of intermediate seismic hazard are designed in accordance with the current Canadian code provisions. Three different design philosophies are considered, namely strong column - weak beam (SCWB), weak column - strong beam (WCSB), and strong column - weak panel zone (SCWP). The performance of these frames is evaluated dynamically by subjecting an inelastic model to an ensemble of 12 actual strong ground motion records. The model takes into account both connection flexibility and panel zone shear deformation. The results are presented in terms of response parameters determined from static pushover analyses, as well as statistical measures of the maximum response parameters determined from the inelastic dynamic analyses. The computed performance of the frames is evaluated in order to assess both the overall level of protection of the frames and the preferred design philosophy. It is concluded that a well-designed and well-detailed ductile moment resisting frame designed using either the SCWB or SCWP design philosophy can withstand ground motions of twice the design level with very little likelihood of collapse, whereas a frame designed using the WCSB approach is ill-conditioned and may develop a collapse mechanism at an excitation level well below twice the design level.Key words: seismic, ductile, steel, frame buildings, performance, design, ductility, damage, inelastic, dynamic.

scholarly journals Comparison of Scaling Ground Motions Using Arithmetic with Logarithm Values for Spectral Matching Procedure

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Rui Zhang ◽  
Dong-sheng Wang ◽  
Xiao-yu Chen ◽  
Hong-nan Li
Keyword(s):  
Ground Motions ◽  
Time History ◽  
Response Spectra ◽  
Time History Analysis ◽  
Spectral Matching ◽  
Moment Resisting Frame ◽  
History Analysis ◽  
Moment Resisting ◽  
Structural Responses ◽  
Structural Time

In recent studies, spectral matching is the most commonly proposed method for selecting earthquake records for time-history analysis of structures. However, until now, there have been no serious investigations of the effects of coordinate values on the scaling of ground motions. This paper investigated the influence of using arithmetic and logarithmic values of response spectra in spectral matching procedures (i.e., ASM and LSM methods) on the results of nonlinear structural time-history analysis. Steel moment resisting frame structures of the 3-, 9-, and 20-stories, which represent low-, medium-, and high-rise buildings, respectively, were used as examples. Structural benchmark responses were determined by calculating the arithmetic mean and median of peak interstory drift ratio (PIDR) demands based on the three record sets developed by the American SAC Steel Project. The three record sets represent seismic hazard levels with 50%, 10%, and 2% probabilities exceeded in 50 years, and their average acceleration spectra were also taken as the target spectrum. Moreover, another 40 record components for selection were scaled both by ASM and LSM methods. The seven components whose spectra were best compatible with the target spectra were selected for the structural time-history analysis. The scale factors obtained by the LSM method are nearly larger than that of the ASM method, and their ranking and selection of records are different. The estimation accuracies of structural mean (median) responses by both methods can be controlled within an engineering acceptable range (±20%), but the LSM method may cause larger structural responses than the ASM method. The LSM method has a better capacity for reducing the variability of structural responses than the ASM method, and this advantage is more significant for longer-period structures (e.g., 20-story structure) with more severe nonlinear responses.

scholarly journals Numerical Study of the Fatigue Crack in Welded Beam-To-Column Connection Using Cohesive Zone Model

2006 ◽  
Vol 324-325 ◽  
pp. 847-850 ◽  
Author(s):  
Cedric Lequesne ◽  
A. Plumier ◽  
H. Degee ◽  
Anne Marie Habraken
Keyword(s):  
Cohesive Zone ◽  
Cohesive Zone Model ◽  
Numerical Study ◽  
Damage Model ◽  
Three Dimensional ◽  
Fatigue Behaviour ◽  
Bending Test ◽  
Zone Model ◽  
Moment Resisting Frame ◽  
Moment Resisting

The fatigue behaviour of the welded beam-to-column connections of steel moment resisting frame in seismic area must be evaluated. The cohesive zone model is an efficient solution to study such connections by finite elements. It respects the energetic conservation and avoids numerical issues. A three-dimensional cohesive zone model element has been implemented in the home made finite element code Lagamine [1]. It is coupled with the fatigue continuum damage model of Lemaître and Chaboche [2]. The cohesive parameters are identified by the inverse method applied on a three points bending test modelling.

Finite Element Analysis of Beam-Column Connection with Cantilever Beam Splicing

2013 ◽  
Vol 838-841 ◽  
pp. 540-544 ◽  
Author(s):  
Jian Rong Pan ◽  
Zhan Wang ◽  
Lin Qiang Zheng ◽  
Zheng Ting Yang
Keyword(s):  
Finite Element ◽  
Cantilever Beam ◽  
Welded Joint ◽  
Three Dimensional ◽  
Element Model ◽  
Rotational Stiffness ◽  
Element Analysis ◽  
Moment Resisting Frame ◽  
Moment Resisting ◽  
Three Dimensional Finite Element

Beam-column connection with cantilever beam bolted-splicing is also known as the joint of column-tree moment-resisting frame. The study is still relatively small for the semi-rigid behavior and rotational stiffness of the joint. This paper deal with four specimens of the joints with cantilever beam splicing and four specimens of the welded joints by using three dimensional finite element model analysis. The strain, stress, yield and ultimate loads, yield and ultimate deformations had been compared between the joint with cantilever beam splicing and the welded joint. The analysis results show that, when the splicing area of the joint with cantilever beam splicing was designed more strongly, the stress distribution, the load-displacement curves in elastic working stage, and the initial rotational stiffness are good agreement between the joint with cantilever beam splicing and the welded joint. The hysteresis curves of the joint with cantilever beam splicing were inverse S-shaped, indicating that there was greater slipping deformation because of bolt splicing. The welded joint had no slipping phenomenon.

Seismic behavior of code-designed medium rise special moment-resisting frame RC buildings in soft soils of Mexico city

2008 ◽  
Vol 30 (12) ◽  
pp. 3681-3707 ◽  
Author(s):  
Arturo Tena-Colunga ◽  
Héctor Correa-Arizmendi ◽  
José Luis Luna-Arroyo ◽  
Gonzalo Gatica-Avilés
Keyword(s):  
Mexico City ◽  
Seismic Behavior ◽  
Rc Buildings ◽  
Soft Soils ◽  
Moment Resisting Frame ◽  
Moment Resisting ◽  
Special Moment Resisting Frame

scholarly journals A practice-oriented method for estimating elastic floor response spectra

2020 ◽  
Vol 53 (3) ◽  
pp. 116-136 ◽  
Author(s):  
Kieran Haymes ◽  
Timothy Sullivan ◽  
Reagan Chandramohan
Keyword(s):  
Response Spectra ◽  
Superposition Method ◽  
Acceleration Response ◽  
Nonstructural Components ◽  
Floor Response Spectra ◽  
Acceleration Response Spectra ◽  
Modal Superposition Method ◽  
Displacement Response Spectra ◽  
Instrumented Buildings ◽  
Floor Acceleration

A practice-oriented modal superposition method for setting elastic floor acceleration response spectra is proposed in this paper. The approach builds on previous contributions in the literature, making specific recommendations to explicitly consider floor displacement response spectra and accounts for uncertainty in modal characteristics. The method aims to provide reliable predictions which improve on existing code methods but maintain simplicity to enable adoption in practical design. This work is motivated by recent seismic events which have illustrated the significant costs that can be incurred following damage to secondary and nonstructural components within buildings, even where the structural system has performed well. This has prompted increased attention to the seismic performance of nonstructural components with questions being raised about the accuracy of design floor acceleration response spectra used in practice. By comparing floor acceleration response spectra predicted by the proposed method with those recorded from instrumented buildings in New Zealand, it is shown that the proposed approach performs well, particularly if a good estimate of the building’s fundamental period of vibration is available.

scholarly journals STRUCTURAL ANALYSIS OF APARTMENT BUILDING WITH SPECIAL RESISTING FRAME SYSTEM

2020 ◽  
Vol 2 (1) ◽  
pp. 9-15
Author(s):  
Sita Ramandhani Arumsari Susanto ◽  
Koespiadi Koespiadi
Keyword(s):  
Soft Soil ◽  
Earthquake Risk ◽  
Seismic Load ◽  
Building Structure ◽  
Apartment Building ◽  
Moment Resisting Frame ◽  
Column Structure ◽  
Moment Resisting ◽  
Frame System ◽  
Special Moment Resisting Frame

Indonesia has a high earthquake risk, therefore several buildings in Indonesia are designed with seismic retention systems where the column structure is designed to be stronger than the beam. The calculation of apartment building structure in this final design is based on SNI 1726:2012 and SNI 2847:2013. The method used in this calculation is the Special Moment Resisting Frame System (SMRFS) because the building area is included in the category of E seismic design which is a type of soft soil. The Special Moment Resisting Frame System is designed so that the building has more strength to withstand earthquakes, especially the column structure. This building is classified as a high-level building, therefore the analysis of seismic load is carried out by Spectrum Response Dynamic, using the SRSS (Square Root of the Sum Squares) method because the building structure has far-flung natural vibration times. In high-rise buildings, it is necessary to control the displacement between floors to reduce the large sway on each floor. The displacement between floors resulting from elastic analysis is less than the maximum allowable intersection between floors. so that the building structure is still safe against swaying.  

Sign in / Sign up

Export Citation Format

Share Document