Behavior of disturbed region of RC precast beams upgraded with near surface mounted CFRP fiber

An innovative strengthening system for dapped-end beams is studied numerically and experimentally in this paper. The system is developed for the half-joint regions of bridge beams also commonly called “gerber saddles”, but it can be adapted to different scenarios. The strengthening system consists of two steel plates that are clamped on both sides of the webs of the beams by means of bolts. The purpose of the system is to transfer the highest possible amount of shear from the concrete webs to the steel plate elements reducing the resistance demand of the concrete half joint. Shear is transferred by friction from concrete to steel plates. The system is designed to be applied on existing bridges without heavy work interesting the carriageway, therefore reducing the interference with the traffic. Some interesting considerations emerge from the study, including the influence of the flange web connection on the structural behavior and the possible presence of brittle failure mechanisms that are difficult to model numerically using f.e.m. simulations.

show abstract

“…• Fiber Reinforced Polymers (FRP) or Carbon Fiber Reinforced Polymers (CFRP) strengthening systems [12,13,[24][25][26][27][28];…”

Section: State Of the Artmentioning

confidence: 99%

Preliminary Investigation on Steel Jacketing Retrofitting of Concrete Bridges Half-Joints

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Below the JSCE curve is a shear brittle failure under low-cycle fatigue and high stress with drastic stiffness reduction; the cracks offer an adverse effect on the fatigue life of the beam, at least 0.5 to one order of increase of experiment as compared with the analysis for the midpoint pulsating load, while below one order could be observed for the offset loading case. Recommended measures are the continuous monitoring and maintenance of the girder, particularly the dapped portion, and provision of an adequate strengthening approach such as the use of CFRP sheet adopted by Quadri ( 53 ) to repair the DEB under static loading, which can be applied for existing RCDEBs. Another strengthening measure is retrofitting of the nib region of DEB with horizontal near-surface mounted steel bars, which leads to an increase in the failure load capacity ( 54 ).…”

Section: Validation Of Numerical Simulationmentioning

confidence: 99%

Numerical Appraisal of Reinforced Concrete Dapped-End Girder Under High-Fatigue Fixed Pulsating and Moving Loads

Quadri

Ali

2023

Transportation Research Record: Journal of the Transportation R

Self Cite

View full text Add to dashboard Cite

This paper presents the numerical evaluation of structural response and fatigue life of a Reinforced Concrete Dapped-End Girder (RCDEB) and associated fatigue life under fixed pulsating and moving loads. For that, a finite element (FE) model of RCDEB is developed using a three-dimensional FE analysis code, Concrete Model of 3-Dimensions (COM3D), and analyzes the FE model under high-fatigue loads by adopting a certain percentage of verified maximum static capacity of the girder. The COM3D system is activated with a multidirectional active crack approach which considers the space averaging of stress–strain in an element. The experimental validation of the numerical analysis is also performed in the laboratory using a small-scale model of the RCDEB under the fixed pulsating load. The experimental validation demonstrates good agreement with the FE analysis. However, the moving load is not considered in the experimental scheme because of the limitation in the testing facility. Finally, it is found from the FE analysis that the moving load, as compared with the fixed pulsating load, has the greatest effect on fatigue performance of the girder, causing about a three-order reduction in fatigue life at the same percentage static capacity of the girder. An increase in the fatigue life of approximately one order is also recorded in the analysis under the static midpoint load of 350 kN as compared with the moving load. Moreover, it is also observed that the reentrant corner of the RCDEB is more vulnerable to fatigue, implying that the hanger bars close to this corner resisted the stresses after the concrete cracked. As a result, strengthening the reentrant zone is recommended.

show abstract

Shear response of reinforced concrete deep beams with and without web opening

Quadri

2023

Innov. Infrastruct. Solut.

View full text Add to dashboard Cite

Behavior of disturbed region of RC precast beams upgraded with near surface mounted CFRP fiber

Cited by 5 publications

References 27 publications

Preliminary Investigation on Steel Jacketing Retrofitting of Concrete Bridges Half-Joints

Preliminary Investigation on Steel Jacketing Retrofitting of Concrete Bridges Half-Joints

Numerical Appraisal of Reinforced Concrete Dapped-End Girder Under High-Fatigue Fixed Pulsating and Moving Loads

Shear response of reinforced concrete deep beams with and without web opening

Contact Info

Product

Resources

About