Repair and Strengthening of Reinforced Concrete Buildings for Seismic Resistance

1991 ◽  
Vol 7 (3) ◽  
pp. 439-459 ◽  
Author(s):  
M. Rodriguez ◽  
R. Park
Keyword(s):  
Reinforced Concrete ◽  
Concrete Columns ◽  
Seismic Resistance ◽  
Longitudinal Reinforcement ◽  
Review Of The Literature ◽  
Reinforced Concrete Buildings ◽  
Seismic Behaviour ◽  
Reinforced Concrete Columns ◽  
Concrete Buildings ◽  
Floor Structure

This paper summarizes a review of the literature on the repair and strengthening of reinforced concrete buildings in seismic areas, with emphasis on the repair and strengthening of reinforced concrete columns. In particular, experimental and analytical investigations are described which provide information on the strength, ductility, and seismic behaviour of reinforced concrete columns repaired and strengthened by jacketing with or without added longitudinal reinforcement placed through the floor structure.

Investigation of Plastic Hinge Length in Reinforced Concrete Columns on Column Behavior

2017 ◽  
Vol 21 ◽  
pp. 45-49
Author(s):  
Mehmet Kamanli ◽  
Alptug Unal
Keyword(s):  
Reinforced Concrete ◽  
Plastic Hinge ◽  
Pushover Analysis ◽  
Concrete Columns ◽  
Analysis Program ◽  
Reinforced Concrete Buildings ◽  
Reinforced Concrete Columns ◽  
Concrete Buildings ◽  
Horizontal Stability ◽  
Plastic Hinge Length

In reinforced concrete buildings in case of a possible earthquake, the buildings slamp as they lost their horizontal stability because of hinging of column ends. The assumptions for plastic hinge lengths are present during project stage of reinforced concrete buildings. According to Turkish Earthquake Regulations, although plastic hinge length is determined to be 0.5h, it's known that plastic hinge length is determined via various formulas in some other regulations all over the world. In reinforced concrete columns, it's necessary to indicate the effect of plastic hinge length on the column behavior. For this purpose, pushover analysis of 5 column samples having different plastic hinge lengths was performed with non-linear analysis program. As a result of pushover analysis, situations of plastic hinges formed in columns and their load-displacement curves were determined. The graphs and the data were compared and the results were discussed.

scholarly journals Experimental analysis of reinforced concrete columns strengthened with Self-Compacting concrete

2010 ◽  
Vol 3 (3) ◽  
pp. 271-283 ◽  
Author(s):  
M. Y. M. Omar ◽  
R. B. Gomes ◽  
A. P. A. Reis
Keyword(s):  
Reinforced Concrete ◽  
Ultimate Load ◽  
Rectangular Cross Section ◽  
Concrete Columns ◽  
Loading Capacity ◽  
Longitudinal Reinforcement ◽  
Self Compacting Concrete ◽  
Reinforced Concrete Columns ◽  
Subsequent Test ◽  
Steel Bars

This paper presents the results of reinforced concrete columns strengthened by addition of a self-compacting concrete overlay at the compressed and at the tensioned face of the member, with and without addition of longitudinal steel bars. Eight columns were submit- ted to loading with an initial eccentricity of 60 mm . These columns had 120 mm x 250 mm of rectangular cross section, 2000 mm in length and four longitudinal reinforcement steel bars with 10 mm in diameter. Reference columns P1 and P2 were tested to failure without any type of rehabilitation. Columns P3 to P8 were loaded to a predefined load (close to the initial yield point of tension reinforce- ment), then unloaded and strengthened for a subsequent test until failure. Results showed that the method of rehabilitation used was effective, increasing the loading capacity of the strengthened pieces by 2 to 5 times the ultimate load of the reference column.

scholarly journals Gravity Load Collapse Behavior of Nonengineered Reinforced Concrete Columns

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Chichaya Boonmee ◽  
Kittipoom Rodsin ◽  
Krissachai Sriboonma
Keyword(s):  
Reinforced Concrete ◽  
Cyclic Loading ◽  
Axial Load ◽  
Concrete Columns ◽  
Poor Quality ◽  
Load Level ◽  
Longitudinal Reinforcement ◽  
Reinforced Concrete Columns ◽  
Gravity Load ◽  
Collapse Behavior

This paper aims at investigating gravity load collapse behavior of extremely poor quality reinforced concrete columns under cyclic loading. Such columns were usually constructed by local people and may not be designed to meet any of the standards. It was found that their concrete strength may be as low as 5 MPa and the amount of longitudinal reinforcement may be lower than 1%. This type of column is deliberately defined as “nonengineered reinforced concrete column,” or NRCC. During earthquake, the gravity load collapse of the NRCC columns caused a large number of death tolls around the world. In this study, four columns as representative of existing NRCC were tested under cyclic loading. The compressive strength of concrete in order of 5 MPa was used to be representative of columns with poor quality concrete. Two axial load levels of 6 and 18 tons were used to study the influence of axial load level on maximum drift at gravity load collapse. To investigate the effect of bar types on drift capacity, 9 mm round bars were used in two specimens and 12 mm deformed bars were used for the rest of the specimens. The maximum drift before gravity load collapse was very dependent on the axial load level. The maximum drift of the specimens subjected to high axial load (18 tons) was extremely low at approximately 1.75% drifts. The use of deformed bars (associated with larger amount of longitudinal reinforcement) caused the damage to severely dissipate all over the height of the columns. Such damage caused columns to collapse at a lower drift compared to those using round bars. Finally, the plastic hinge model was used to predict the maximum drift of the low strength columns. It was found that the model overly underestimates the drift at gravity load collapse.

scholarly journals Behaviour of Rectangular Reinforced Concrete Columns with Disproportionate Cross-Section Dimensions Subjected to Compression and Biaxial Bending - Case Study

2020 ◽  
Vol 9 (1) ◽  
pp. 94-107
Author(s):  
Savu Adrian-Alexandru
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Seismic Design ◽  
Concrete Columns ◽  
Biaxial Bending ◽  
Seismic Behaviour ◽  
Reinforced Concrete Columns ◽  
Seismic Design Code ◽  
Interaction Curves

Abstract The purpose of the current paper is to raise awareness on the behaviour of rectangular reinforced concrete columns with disproportionate cross-section dimensions subjected to compression and biaxial bending, considering the fact that in the current structural design process, the design of columns is usually done with respect to each of the two principal directions without considering their combined effect. The paper is based on a case study regarding a building that is currently in the design phase, in which to obtain a correct seismic behaviour, rectangular columns with disproportionate cross-section dimensions were used. The design of both the building and the columns follows the Romanian seismic design codes (“P100-1/2013 - Seismic design code - Part 1 - Design provisions for buildings” and “SR-EN 1998/2004 - Design of structures for earthquake resistance”). Results were compared and conclusions were drawn based on the interaction curves and interaction surfaces computed with expressions from specialized literature and sectional analysis software.

scholarly journals Comparative study on acceptance criteria for non-ductile reinforced concrete columns

2018 ◽  
Vol 51 (4) ◽  
pp. 183-196
Author(s):  
Opabola Eyitayo ◽  
Kenneth J. Elwood
Keyword(s):  
Reinforced Concrete ◽  
Failure Mode ◽  
Concrete Columns ◽  
Deformation Capacity ◽  
Existing Buildings ◽  
Acceptance Criteria ◽  
Reinforced Concrete Columns ◽  
Seismic Demands ◽  
Concrete Buildings ◽  
Direct Rotation

Poor seismic performance of older reinforced concrete buildings in past seismic events has frequently been attributed to failure of non-ductile columns not detailed for seismic demands. The Seismic Assessment of Existing Buildings Guidelines developed in New Zealand (NZ Guideline) provides a performance-based engineering framework for assessment of existing buildings, with concrete buildings covered in section C5. This study compares the probable failure mode and deformation capacity assessed based on NZ Guideline, ASCE/SEI 41-13, and ASCE/SEI 41-17 with the results from quasi-static cyclic tests conducted on 52 rectangular and 13 circular reinforced concrete columns with reinforcement details similar to those of non-ductile columns. Results indicate that the general curvature-based method of the NZ Guideline was not able to identify the observed failure mode but generally provides a conservative estimate of deformation capacity in comparison with ASCE/SEI 41-17. Based on the results of this study, a direct rotation-based acceptance criteria is proposed for NZ Guidelines. Also, slight modifications, to reduce conservatism, have been proposed for the curvature-based method.

Sign in / Sign up

Export Citation Format

Share Document