Retrofit of Concrete Columns with Inadequate Lap Splices by the Use of Rectangular Steel Jackets

1996 ◽  
Vol 12 (4) ◽  
pp. 693-714 ◽  
Author(s):  
Riyad S. Aboutaha ◽  
Michael D. Engelhardt ◽  
James O. Jirsa ◽  
Michael E. Kreger
Keyword(s):  
Reinforced Concrete ◽  
Large Scale ◽  
Concrete Columns ◽  
Seismic Retrofit ◽  
Design Guidelines ◽  
Reinforced Concrete Frame ◽  
Reinforced Concrete Columns ◽  
Lap Splice ◽  
Concrete Frame ◽  
Anchor Bolts

This paper describes an experimental research program on the use of rectangular steel jackets for seismic retrofit of non-ductile reinforced concrete frame columns. Eleven large scale columns were tested to examine the effectiveness of various types of steel jackets for improving the ductility and strength of columns with an inadequate lap splice in the longitudinal reinforcement. Response of the columns before and after being strengthened with steel jackets was examined. Several types of steel jackets were investigated, including rectangular solid steel jackets with and without adhesive anchor bolts. The test results indicate that a thin rectangular steel jacket combined with adhesive anchor bolts can be a highly effective retrofit measure for reinforced concrete columns with an inadequate lap splice. Design guidelines for the use of rectangular steel jackets as a seismic retrofit for non-ductile reinforced concrete columns are presented.

scholarly journals Using rigidity elements to strengthen one-storey buildings frames

2018 ◽  
Vol 196 ◽  
pp. 02017
Author(s):  
Oleg Veremeenko
Keyword(s):  
Reinforced Concrete ◽  
Concrete Columns ◽  
Reinforced Concrete Frame ◽  
Limit Values ◽  
Building Frame ◽  
Concrete Frame ◽  
Industrial Buildings ◽  
Calculation Results ◽  
Force Variation ◽  
Influence Degree

The study focuses on strengthening industrial buildings frames by introducing rigidity elements. Materials concentration principle in rigidity elements in the form of reinforced concrete columns is used and the influence degree on a building frame operation is estimated. This changes the performance of the overlay disk as an element that distributes horizontal forces. The paper describes basic dependencies determining the correlation between rigidity characteristics of rigidity elements and ordinary columns. They are determined by reinforced concrete frame movements when the lower section columns moments reach limit values. In resulting exposure rigidity elements accept basic horizontal efforts, and ordinary columns work as centrally compressed. Calculation results are presented as graphs of force variation depending on correlation between rigidity characteristics of rigidity elements and ordinary columns. The paper outlines that after introducing rigidity elements they act as basic distributing horizontal loads element. The overlay disk has the final load bearing capacity and regulates the limit distances between rigidity elements. The introduction of rigidity elements into the building frame should be accompanied by appropriate measures to strengthen structure foundations. The research proves that this method of one-storey industrial buildings frames reinforcement enables to use materials and technologies during reconstruction more efficiently.

SEISMIC RETROFIT OF NONDUCTILE REINFORCED CONCRETE FRAME AND MASONRY BUILDINGS

2019 ◽  
Vol 2 (Special Issue on First SACEE'19) ◽  
pp. 143-164
Author(s):  
Murat Saatcioglu
Keyword(s):  
Reinforced Concrete ◽  
Seismic Risk ◽  
Seismic Vulnerability ◽  
Risk Mitigation ◽  
Seismic Retrofit ◽  
Masonry Wall ◽  
System Level ◽  
Reinforced Concrete Frame ◽  
Existing Building ◽  
Concrete Frame

A large proportion of existing building and bridge infrastructure across the world consists of seismically deficient non-ductile structural systems. Performance of structures during recent earthquakes have demonstrated seismic vulnerability of these systems, the majority of which were designed prior to the enactment of modern seismic codes, though some were designed more recently in areas where code enforcement provides challenges. These structures constitute considerable seismic risk, especially in large metropolitan centres. Because it is economically not feasible to replace a large segment of seismically deficient infrastructure with new and improved systems, retrofitting existing structures remains to be a viable seismic risk mitigation strategy. The objective of this paper is to highlight seismic retrofit strategies for deficient building and bridge infrastructures, with emphasis on experimental and analytical research conducted at the University of Ottawa. The retrofit strategies consist of structural upgrades at the system level, as well as at the element level. Non-ductile reinforced concrete frame retrofits, in the form of lateral bracing techniques, and concrete column and masonry wall retrofit methodologies are discussed. The use of innovative materials and techniques are presented.

Sign in / Sign up

Export Citation Format

Share Document