Seismic Performance of Self-Centering UHPC Retainers Applied to Medium-Small Span Concrete Bridges

2019 ◽  
Author(s):  
Wenpeng Wu ◽  
Shiguo Long ◽  
Huihui Li
Keyword(s):  
Seismic Performance ◽  
Seismic Design ◽  
High Performance ◽  
Load Transfer ◽  
High Performance Concrete ◽  
Design Method ◽  
Structural Characteristics ◽  
Time History ◽  
Nonlinear Time History Analysis ◽  
Seismic Resistant

<p>Seismic resistant retainer is an important component for seismic design of the medium‐small span bridges. However, it’s difficult for the bridge engineers to design a reasonable transverse retainer due to deficiency of design detail in most of current seismic design specifications. Therefore, this paper proposed a prestressed prefabricated concrete retainer that utilize the ultra‐high performance concrete (UHPC). Firstly, the structural characteristics and the seismic design method of the new proposed retainer is illustrated. The OpenSEES model of the case‐study bridge were simulated by considering three different types of seismic resistant retainers. A total of ten high intensity ground motions were selected to conduct the nonlinear time history analysis (NTHA). Subsequently, to investigate the seismic performance of the proposed UHPC retainer, this paper performs the comparative study of seismic responses for different bridge components. It is concluded that, the proposed retainer can provide excellent displacement capacity and help to reduce the seismic damage of bridge piers significantly. In addition, the new retainer has strong ability to keep self‐centering to help the bridge reducing the residual displacement of superstructure under strong seismic events. The proposed UHPC retainer is applicable to the rapid prestressed prefabricated construction process and has a clear load transfer mode under earthquake actions. Therefore, it is a good candidate to the multi‐level performance‐based seismic design of the medium‐small span bridges.</p>

STUDY ON PERFORMANCE-BASED SEISMIC DESIGN OF SHANGHAI WORLD FINANCIAL CENTER TOWER

2009 ◽  
Vol 03 (04) ◽  
pp. 273-284 ◽  
Author(s):  
XILIN LU ◽  
JIEJIANG ZHU ◽  
YUN ZOU
Keyword(s):  
Seismic Performance ◽  
Seismic Design ◽  
Time History ◽  
Shaking Table ◽  
Nonlinear Time History Analysis ◽  
Distribution Analysis ◽  
Element Analysis ◽  
Analytical Studies ◽  
Performance Based Seismic Design ◽  
Financial Center

The height of 101-storey Shanghai World Financial Center Tower is 492 m above ground. According to the philosophy of performance-based seismic design, the seismic performance design objectives and corresponding parameters were proposed for the structure under various seismic actions from frequent to rare earthquake levels. Analytical studies including refined finite element analysis, nonlinear time-history analysis, and stress distribution analysis on the important joint have been conducted to evaluate the structural seismic performance. Along with the analytical studies, shaking table model test and the important joint tests have been carried on in order to verify the accuracies of the analytical results as well as to complement the analytical studies. The results obtained from the studies demonstrate that the structural system meets the performance-based design objectives presented in the paper.

Structural Performance of Automated Multi-Depth Shuttle Warehouses (Amsws) Under Low-to-Moderate Seismic Actions

2021 ◽  
Author(s):  
Aleksei Kondratenko ◽  
Alper Kanyilmaz ◽  
Carlo Andrea Castiglioni ◽  
Francesco Morelli ◽  
Mohsen Kohrangi
Keyword(s):  
Seismic Design ◽  
Brittle Failure ◽  
Structural Characteristics ◽  
Time History ◽  
Steel Structures ◽  
Current Approach ◽  
Structural Performance ◽  
Future Design ◽  
The Future ◽  
Base Connections

Abstract Automated Multi-Depth Shuttle Warehouses (AMSWs) are compact storage systems that provide a large surface occupation and therefore maximum storage density. AMSWs represent the future of storage technology, providing substantial savings in terms of cost, space, and energy with respect to traditional warehouses. Currently, designers refer to the standard building codes for the seismic design of AMSWs. Since structural characteristics of AMSWs are considerably different from the steel structures of typical buildings, this current approach used by designers is questionable in terms of safety and efficiency. In this article, the behavior of 5 AMSW structures has been studied performing 150 time-history analyses by direct integration including P-Delta effects. Demand/capacity ratios calculated for each element showed the dominance of the brittle failure mechanism in AMSWs subjected to low-to-moderate seismic actions. These mechanisms mainly took place in upright columns and their base connections prior to the activation of ductile energy dissipation mechanisms of the structure. Based on the results, further improvements have been recommended for the future design provisions, which may lead to a safer seismic design of AMSWs.

Effect of bidirectional excitation on seismic performance of regular RC frame buildings designed for modern codes

2021 ◽  
pp. 875529302110478
Author(s):  
Payal Gwalani ◽  
Yogendra Singh ◽  
Humberto Varum
Keyword(s):  
Seismic Performance ◽  
Time History ◽  
Nonlinear Time History Analysis ◽  
Inelastic Behavior ◽  
Moment Frame ◽  
Frame Buildings ◽  
Bidirectional Excitation ◽  
Rc Frame Buildings ◽  
Nonlinear Time History ◽  
Hinge Model

The existing practice to estimate seismic performance of a regular building is to carry out nonlinear time history analysis using two-dimensional models subjected to unidirectional excitations, even though the multiple components of ground motion can affect the seismic response, significantly. During seismic shaking, columns are invariably subjected to bending in two orthogonal vertical planes, which leads to a complex interaction of axial force with the biaxial bending moments. This article compares the seismic performance of regular and symmetric RC moment frame buildings for unidirectional and bidirectional ground motions. The buildings are designed and detailed according to the Indian codes, which are at par with the other modern seismic codes. A fiber-hinge model, duly calibrated with the biaxial experimental results, is utilized to simulate the inelastic behavior of columns under bidirectional bending. A comparison of the estimated seismic collapse capacity is presented, illustrating the importance of considering the bidirectional effects. The results from fragility analysis indicate that the failure probabilities of buildings under the bidirectional excitation are significantly higher as compared to those obtained under the unidirectional excitation.

Direct Displacement Procedure for Performance-Based Seismic Design of Mid-Rise Wood-Framed Structures

2009 ◽  
Vol 25 (3) ◽  
pp. 583-605 ◽  
Author(s):  
Wei Chiang Pang ◽  
David V. Rosowsky
Keyword(s):  
Seismic Design ◽  
Response Spectrum ◽  
Design Procedure ◽  
Time History ◽  
Time History Analysis ◽  
Nonlinear Time History Analysis ◽  
Framed Structures ◽  
History Analysis ◽  
Performance Based Seismic Design ◽  
Nonlinear Time History

This paper presents a direct displacement design (DDD) procedure that can be used for seismic design of multistory wood-framed structures. The proposed procedure is applicable to any pure shear deforming system. The design procedure is a promising design tool for performance-based seismic design since it allows consideration of multiple performance objectives (e.g., damage limitation, safety requirements) without requiring the engineer to perform a complex finite element or nonlinear time-history analysis of the complete structure. A simple procedure based on normalized modal analysis is used to convert the code-specified acceleration response spectrum into a set of interstory drift spectra. These spectra can be used to determine the minimum stiffness required for each floor based on the drift limit requirements. Specific shear walls can then be directly selected from a database of backbone curves. The procedure is illustrated on the design of two three-story ATC-63 archetype buildings, and the results are validated using nonlinear time-history analysis.

scholarly journals Seismic Fragility Analysis of Multispan Reinforced Concrete Bridges Using Mainshock-Aftershock Sequences

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yutao Pang ◽  
Li Wu
Keyword(s):  
Reinforced Concrete ◽  
Earthquake Engineering ◽  
Design Method ◽  
Fragility Curves ◽  
Uniform Design ◽  
Time History ◽  
Fragility Analysis ◽  
Nonlinear Time History Analysis ◽  
Aftershock Sequences ◽  
System Fragility

Although the knowledge and technology of performance-based earthquake engineering have rapidly advanced in the past several decades, current seismic design codes simply ignore the effect of aftershocks on the performance of structures. Thus, the present paper investigated the effect of aftershocks on seismic responses of multispan reinforced concrete (RC) bridges using the fragility-based numerical approach. For that purpose, a continuous girder RC bridge class containing 8 bridges was selected based on the statistical analysis of the existing RC bridges in China. 75 recorded mainshock-aftershock seismic sequences from 10 well-known earthquakes were selected in this study. In order to account for the uncertainty of modeling parameters, uniform design method was applied as the sampling method for generating the samples for fragility analysis. Fragility curves were then developed using nonlinear time-history analysis in terms of the peak curvature of pier column and displacement of bearings. Finally, the system fragility curves were derived by implementing Monte Carlo simulation on multinormal distribution of two components. From the results of this investigation, it was found that, for the RC continuous bridges, the influence of aftershocks can be harmful to both bridge components and system, which increases both the component fragility of the displacement of bearings and seismic curvature of pier sections and system fragility.

scholarly journals Energy-Based Seismic Design Method for EBFs Based on Hysteretic Energy Spectra and Accumulated Ductility Ratio Spectra

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Cuiling Ma
Keyword(s):  
Seismic Design ◽  
Design Method ◽  
Time History ◽  
Soil Classification ◽  
Nonlinear Static Analysis ◽  
Energy Spectra ◽  
Hysteretic Energy ◽  
Shear Links ◽  
Seismic Design Method ◽  
Ductility Ratio

In the case of far field earthquakes, structural failure often results from accumulated damage caused by cyclic effects and gradual accumulation of energy. This paper proposes an energy-based seismic design method for steel eccentrically braced frames (EBFs) with two shear links at every story according to the energy balance concept. The proposed method is theoretically supported by hysteretic energy spectra and accumulated ductility ratio spectra according to the Chinese soil classification. Furthermore, the method can be used to clarify the relationship between cumulative hysteretic energy and one-way pushover energy. For developing the method, it is assumed that all the hysteretic energy is dissipated by the shear links, column bases, and beam ends of the frames at both sides. Therefore, the parts outside the links, including beam segments, braces, and columns, are specially designed to perform elastically during an earthquake. Furthermore, a V-scheme steel EBF with ten stories and three spans is designed. The seismic performances of the designed structure, such as story drift and energy dissipation, are evaluated by nonlinear static analysis and time-history analysis. Finally, the reliability and accuracy of the proposed seismic design method are validated.

Strengthening Research in the Longitudinal Frames of Prefabricated Structures with Viscous Dampers

2013 ◽  
Vol 671-674 ◽  
pp. 782-785
Author(s):  
Bin He ◽  
Jin Lai Pang ◽  
Cheng Qing Liu
Keyword(s):  
Seismic Performance ◽  
Pushover Analysis ◽  
Vertical Direction ◽  
Time History ◽  
Nonlinear Time History Analysis ◽  
Viscous Dampers ◽  
Existing Building ◽  
Concrete Frame ◽  
Uniform Drift ◽  
Nonlinear Time History

For the lack of research in the longitudinal frame of prefabricated structure for its weak lateral stiffness, pushover analysis is conducted to evaluate the seismic performance of a fabricated concrete frame. Based on case study, the strengthening strategies with viscous dampers are analyzed. In view of the undesirable drift distribution and failure mode in the existing building, it is believed that arrangement of dampers should be designed to attain a uniform drift distribution. Based on the nonlinear time history analysis method, the strategy of damper allocation in vertical direction of the structure is investigated .Results indicate that a proper design might be attained based on the property of existing system, leading to a uniform drift distribution and better seismic performance.

The Passive Control Seismic Strengthen about RC Frame Infilled Wall Structure

2013 ◽  
Vol 405-408 ◽  
pp. 1056-1062
Author(s):  
Qing Li Meng ◽  
Jun Chen ◽  
Chun Yu Chu
Keyword(s):  
Seismic Performance ◽  
Passive Control ◽  
Time History ◽  
Nonlinear Time History Analysis ◽  
Wall Structure ◽  
Rc Frame ◽  
Reinforced Concrete Frame ◽  
Direction Parallel ◽  
Plane Direction ◽  
Performance Target

In this paper, a four-storey reinforced concrete frame infilled wall structure does not meet the seismic perform target, based on the seismic behavior target of both frame and infilled wall, to carry out the study on the passive control seismic strengthen of RC infilled wall structure with attached dampers. First, two kinds of passive control strengthen schemes were put forward. Scheme 1: Dampers were installed in the in-plane direction parallel with all 1-storey infilled walls; Scheme 2: Dampers were installed in the in-plane direction parallel with all 1-storey and 2-storey infilled walls. Then to establish the two types of passive control seismic strengthen model in OpenSees, carry out the rare earthquake nonlinear time-history analysis under El Centro, Parkfield and San Fenando ground motions. Finally, in accordance with the seismic performance target quantization index of RC Frame infilled wall structure used as hospital, i.e. considering storey drift ratio limit and infilled wall damage, judge the scheme 2 can meets the seismic performance target.

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