Design Forces for Drift and Damage Control: A Second Look at the Substitute Structure Approach

This paper explores the development of a method that is useful for design of reinforced concrete (RC) frame structures to resist earthquakes. The substitute structure method, originally proposed in the 1970s, makes an analogy between viscously damped linear and hysteretic response for the purpose of estimating maximum displacement. The evolution of the method is retraced in order to emphasize its unique reliance on experimental results, which are needed to establish rules for assignment of substitute linear properties. Recent dynamic test results are used to extend significantly the calibration of the method, which furnishes design loads on the basis of drift and damage control.

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Investigation of Global Equivalent Damping and Statistical Relationship of Displacement between Nonlinear Static and Dynamic Analysis of Reinforced Concrete Frame Structures

Earthquake Spectra ◽

10.1193/021517eqs031m ◽

2018 ◽

Vol 34 (3) ◽

pp. 1311-1338 ◽

Cited By ~ 3

Author(s):

Lulu Yan ◽

Jinxin Gong ◽

Qin Zhang

Keyword(s):

Reinforced Concrete ◽

Degree Of Freedom ◽

Design Parameters ◽

Frame Structures ◽

Equivalent Linearization ◽

Rc Frame ◽

Static And Dynamic Analysis ◽

Equivalent Damping ◽

Nonlinear Static ◽

Rc Frame Structures

The assessment of the seismic performance of reinforced concrete (RC) frame structures using the equivalent linearization approach requires comprehensive insight into the nonlinear response of the system, and most previous researches focused on the analysis of a single-degree-of-freedom (SDOF) system. To describe the hysteretic behavior of a multi-degree-of-freedom (MDOF) system accurately, monotonic and cyclic pushover analyses for 88 RC frames structures with various configurations and design parameters are carried out and a unified hysteresis loop expression modeling the cyclic pushover results of RC frame system is developed. Then, a global equivalent damping based on Jacobsen's approach is derived, and comparisons between the displacements obtained by nonlinear static analysis (NSA) utilizing the derived global equivalent damping and those obtained by nonlinear time history analysis (NTHA) are made. Finally, a modified global equivalent damping is presented by calibrating the derived Jacobsen's equivalent damping through NTHA results. Based on the modified equivalent damping, the statistical analysis of the ratios of the results obtained by NTHA to those obtained by NSA is implemented to predicate the probabilistic seismic displacement demands of RC frame structures.

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Probabilistic Evaluation of Effects of Column Moment Magnification Factor on Seismic Performance of Reinforced Concrete Frames

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.251 ◽

2011 ◽

Vol 243-249 ◽

pp. 251-257 ◽

Cited By ~ 1

Author(s):

Ming Ji He ◽

Chun Yang ◽

Jian Cai ◽

Yan Sheng Huang ◽

Yi Wu

Keyword(s):

Reinforced Concrete ◽

Failure Mode ◽

Seismic Performance ◽

Seismic Vulnerability ◽

Failure Modes ◽

Fragility Curves ◽

Frame Structures ◽

Rc Frame ◽

Magnification Factor ◽

Rc Frame Structures

Enhancing column flexural capacity is the key measure in seismic capacity design to achieve strong column-weak beam failure mode and determinate the probabilistic relation between column moment magnification factor (CMMF). In the paper the effects of column moment magnification factor on seismic performance of reinforced concrete (RC) frames are evaluated to limit the occurrence probability of column-hinging failure modes within an acceptable tolerance. Monte Carlo simulation methodology is used to calculate the probability of drift demand exceeding drift capacity of two typical frame structures with consideration of major uncertainties. And fragility curves are constructed to obtain the relationship between CMMF and probability of structural damages and assess the seismic vulnerability of RC frame structures. Results show that the seismic performance of RC frame structures can be significantly enhanced by improving CMMF. The CMMF is required to be equal to or greater than 2.0 to achieve acceptable probability of exceedance of column-hinging failure mode.

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In-Plane Cyclic Test on Framed Dry-Stack Masonry Panel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.3899 ◽

2010 ◽

Vol 163-167 ◽

pp. 3899-3903 ◽

Cited By ~ 4

Author(s):

Kun Lin ◽

Yuri Z. Totoev ◽

Hong Jun Liu

Keyword(s):

Cyclic Test ◽

Frame Structures ◽

Rc Frame ◽

Test Results ◽

Seismic Behaviour ◽

Energy Dissipation Capacity ◽

Frictional Energy Dissipation ◽

Rc Frame Structures ◽

Masonry Units ◽

New System

A new masonry system has been developed to improve the seismic behaviour of RC frame with masonry panels. In this system dry-stack masonry panels are built with masonry units capable of sliding in-plane of a panel. These masonry panels have reduced in-plane stiffness but increased frictional energy dissipation capacity compared with the traditional masonry panels. Under seismic or wind loads these panels do not detrimentally interfere with natural RC frame response but rather positively contribute to it mainly by increasing dumping. A cyclic test has been performed to evaluate the behaviour of this masonry system. Test results demonstrate that the new system can improve the seismic behaviour of RC frame structures with masonry panels.

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A load increment method for ductile reinforced concrete (RC) frame structures considering strain hardening effects

STRUCTURAL ENGINEERING AND MECHANICS ◽

10.12989/sem.2011.38.2.231 ◽

2011 ◽

Vol 38 (2) ◽

pp. 231-247 ◽

Cited By ~ 2

Author(s):

M. Gunhan Aksoylu ◽

Konuralp Girgin

Keyword(s):

Reinforced Concrete ◽

Strain Hardening ◽

Frame Structures ◽

Rc Frame ◽

Load Increment ◽

Rc Frame Structures

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Analysis on Progressive Collapse Resistance of Reinforced Concrete Frame Structures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.717 ◽

2011 ◽

Vol 243-249 ◽

pp. 717-723

Author(s):

Jin Gang Xiong ◽

Yon Kang Zheng ◽

Guan Min Cai ◽

Yan Li

Keyword(s):

Reinforced Concrete ◽

Seismic Design ◽

Progressive Collapse ◽

Frame Structures ◽

Rc Frame ◽

Reinforced Concrete Frame ◽

Concrete Frame ◽

Collapse Resistance ◽

Rc Frame Structures ◽

Reinforced Concrete Frame Structures

In this paper the analysis is conducted to investigate the progressive collapse resistance of typical reinforced concrete(RC) multi-story frame structures, which are designed according to the China code for seismic design of buildings. The analysis results show that the progressive collapse resistance will be enhanced with the seismic fortification intensity increasing. The progressive collapse resistance of RC frame structures with low seismic fortification intensity are poor. This implies that as for RC frame structures with low seismic or non-seismic demand, close attention must be paid to continuity and ductility in order to prevent progressive collapse.

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Performance of School Buildings during the 2002 Molise, Italy, Earthquake

Earthquake Spectra ◽

10.1193/1.1769374 ◽

2004 ◽

Vol 20 (1_suppl) ◽

pp. 257-270 ◽

Cited By ~ 32

Author(s):

Nicola Augenti ◽

Edoardo Cosenza ◽

Mauro Dolce ◽

Gaetano Manfredi ◽

Angelo Masi ◽

...

Keyword(s):

Reinforced Concrete ◽

Secondary Schools ◽

Frame Structures ◽

School Buildings ◽

Rc Frame ◽

Masonry Structures ◽

Structural Types ◽

Rc Frame Structures ◽

Almost All

The authors inspected approximately 300 primary and secondary schools in 87 municipalities of Molise. About 40% were masonry structures, 40% were reinforced concrete (RC) frame structures, and the remaining 20% were a variety of structures. Almost all of them were built without seismic criteria and most had no more than three stories. In this paper we compare the distribution of the damage with the vulnerability classes. The collapses in San Giuliano di Puglia highlight the comparative vulnerabilities related to structural types, construction phases, and location.

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Damage Control for Clay Masonry Infills in the Design of RC Frame Structures

Journal of Earthquake Engineering ◽

10.1080/13632469.2012.670575 ◽

2012 ◽

Vol 16 (sup1) ◽

pp. 1-35 ◽

Cited By ~ 64

Author(s):

S. Hak ◽

P. Morandi ◽

G. Magenes ◽

T. J. Sullivan

Keyword(s):

Damage Control ◽

Frame Structures ◽

Rc Frame ◽

Masonry Infills ◽

Rc Frame Structures

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Collapse Simulation of Damaged Reinforced Concrete Frame Structures in Earthquakes

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.1011 ◽

2019 ◽

Author(s):

Yang Yang ◽

Xianglin Gu

Keyword(s):

Reinforced Concrete ◽

Full Range ◽

Simulation System ◽

Frame Structures ◽

Rc Frame ◽

Steel Bar ◽

Damage States ◽

Collapse Behavior ◽

Rc Frame Structures ◽

The Impact

<p>A simulation system based on the discrete element method (DEM) was developed to simulate the collapse behavior of damaged reinforced concrete (RC) frame structures in earthquakes. A frame structure was discretized into beam-column-joint discrete system according to its failure mode. The elements were assumed to be cuboid, and a group of concrete springs and steel bar springs were set between two adjacent elements to represent their interactions. The failure of material was initiated by fracture of springs, and the impact actions among separated components were considered. Using the simulation system, the full-range collapse process of an RC frame, including debris stacking, was visually simulated. The efficiency of the system was verified by comparing the simulated collapse behavior with that observed in a collapse experiment. A new method, in which concrete springs and steel bar springs were cut off in advance to simulate the respective initial imperfection, was proposed to model earthquake-induced damage states of RC frame structures. Then displacement loadings were conducted to form the respective damage states. Finally, a parametric analysis was conducted to investigate the collapse processes of the RC frame with different scenarios of initial damage. The results indicated that the initial damages on columns were of greater influence on collapse patterns than the initial damages on beams, and the residual interstory drifts were nonnegligible in evaluating the structural collapse resistance.</p>

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Seismic Performance of Reinforced Concrete Frame Buildings in Southern California

Earthquake Spectra ◽

10.1193/1.3570684 ◽

2011 ◽

Vol 27 (2) ◽

pp. 399-418 ◽

Cited By ~ 10

Author(s):

Kathryn P. Lynch ◽

Kristen L. Rowe ◽

Abbie B. Liel

Keyword(s):

Reinforced Concrete ◽

Los Angeles ◽

Seismic Performance ◽

Southern California ◽

Frame Structures ◽

Rc Frame ◽

Frame Buildings ◽

Rc Frame Structures ◽

Rc Frame Buildings ◽

The Impact

This study examines the impact of the ShakeOut earthquake on reinforced concrete (RC) frame structures in Southern California. The assessment uses synthetic ground motions and nonlinear dynamic analysis to evaluate 20 RC frame buildings hypothetically located at 735 sites throughout the region. Results show that older nonductile RC frame structures may collapse at 8% to 32% of the sites analyzed, especially in Palm Springs, Los Angeles, and San Bernardino. Modern code-conforming RC frame structures are predicted to collapse at fewer sites (1–11%), but modern midrise construction may be vulnerable in Los Angeles due to rupture directivity and basin effects. These seismic performance metrics can inform the development of policies for emergency response and for mitigating earthquake-induced collapse of existing RC frame buildings. The study further provides a prototype that can be used in developing future scenario studies that will benefit from ongoing research to improve building and seismological models.

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