Empirical Expressions for Deformation Capacity of Reinforced Concrete Structural Walls

To resolve the undesirable effects of reinforced concrete non-structural walls to the earthquake behaviour of structural members, weak points (called "Structural Slits") are intentionally provided at the connection between structural members and non-structural walls. This paper presents an estimation method for the stress developed in the "Structural Slits" which are applied to the non-structural walls of reinforced concrete high-rise residential buildings.

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Seismic Rehabilitation of a School Building in Cephalonia, Greece

Case Studies on Conservation and Seismic Strengthening/Retrofitting of Existing Structures ◽

10.2749/cs002.001 ◽

2020 ◽

pp. 1-20

Author(s):

Christos Giarlelis ◽

Evlalia Lamprinou ◽

Constantinos Repapis

Keyword(s):

Reinforced Concrete ◽

Response Spectrum ◽

Earthquake Sequence ◽

School Building ◽

Structural Walls ◽

Concrete Walls ◽

Seismic Rehabilitation ◽

Reinforced Concrete Walls ◽

Structural Capacity ◽

Structural Failures

<p>The 2014 earthquake sequence in Cephalonia, Greece, resulted in a number of structural failures. In Argostoli, the capital of the island, a school building suffered light damage; however, the structural assessment following the analysis procedures of the recently published Greek Code for Structural Interventions, showed that seismic strengthening is required. The structure was built on the aftermath of the catastrophic 1953 Ionian earthquake sequence based on older code requirements, which are much outdated, as indicated from the results of both modal response spectrum analyses and non-linear static analyses. The retrofit aims to increase the very low structural capacity of the building and as a means for that the use of concrete jackets is selected. Based on the results of the assessment, it was decided that concrete jackets should be applied to all columns, while large structural walls running along the transversal direction were strengthened with single-sided reinforced concrete jacketing. The interventions are limited by architectural demands and cost considerations. However, analyses of the strengthened structure show that the interventions improve its seismic behaviour adequately. The detailing of interventions is thoroughly presented. What makes this case study interesting is the unusual structural system of the building, which is an ingenious combination of frame elements and lightly reinforced concrete walls and its behaviour to one of the strongest recent Greek earthquakes. The rehabilitation study had to model correctly the structure and propose interventions that were in agreement with the architectural demands and the cost consideration.</p>

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Guest editorial: Nonlinear modelling of reinforced concrete structural walls

Bulletin of Earthquake Engineering ◽

10.1007/s10518-019-00715-z ◽

2019 ◽

Vol 17 (12) ◽

pp. 6359-6368 ◽

Cited By ~ 1

Author(s):

M. Fischinger ◽

T. Isaković ◽

K. Kolozvari ◽

J. Wallace

Keyword(s):

Reinforced Concrete ◽

Guest Editorial ◽

Structural Walls ◽

Nonlinear Modelling

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Deformation Capacity Limits for Reinforced Concrete Walls

Earthquake Spectra ◽

10.1193/080118eqs193m ◽

2019 ◽

Vol 35 (3) ◽

pp. 1189-1212 ◽

Cited By ~ 2

Author(s):

Alex V. Shegay ◽

Christopher J. Motter ◽

Kenneth J. Elwood ◽

Richard S. Henry

Keyword(s):

Reinforced Concrete ◽

Compressive Strain ◽

Deformation Capacity ◽

Concrete Walls ◽

Capacity Limits ◽

Reinforced Concrete Walls ◽

Proposed Model ◽

Bar Buckling ◽

Bar Diameter ◽

Different Levels

The use of deformation capacity limits is becoming increasingly common in seismic design and assessment of reinforced concrete (RC) walls. Deformation capacity limits for RC walls in existing design and assessment documents are reviewed using a comprehensive database. It is found that the existing models are inconsistent and do not account for variation in deformation capacity with changes in the ratio of neutral axis depth to wall length ( c/ L w) and ratio of transverse reinforcement spacing to longitudinal bar diameter ( s/ d b) at the wall end region. A new mechanics-based model considering strain limits on the concrete and reinforcement is recommended. Concrete compressive strain limits for different levels of wall end region detailing are selected based on curvature ductilities for the walls in the database. Reinforcement tensile strain is limited based on a model for bar buckling. The proposed model, which accounts for c/ L w and s/ d b, is shown to have less dispersion and more accuracy than existing models when compared against experimental data and provides consistency between assessment and design provisions.

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