Performance Analysis of Reinforced Concrete Structures Strengthened with BFRP

2013 ◽  
Vol 712-715 ◽  
pp. 966-969 ◽  
Author(s):  
Ze Bao Kan ◽  
Yan Ru Li
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Performance Analysis ◽  
Seismic Performance ◽  
Present Status ◽  
Concrete Structure ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Reinforced Concrete Structures ◽  
Reinforced Concrete Structure

The present status of reinforced concrete structure confined by FRP is introduced, and the recent technical researches of reinforced concrete beams and columns confined by BFRP are summarized. Based on those researches, the mechanical properties and calculation models are analyzed. At the same time, the seismic performance of reinforced concrete beams and columns confined by BFRP is also explored.

scholarly journals Calculation of damage RC constructions according to deformation model

2020 ◽  
Vol 2020 (2) ◽  
pp. 99-106
Author(s):  
Yaroslav Blikharskyy ◽  
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Concrete Beams ◽  
Concrete Structures ◽  
Physical And Mechanical Properties ◽  
Reinforced Concrete Beams ◽  
Core Material ◽  
Deformation Model ◽  
Reinforced Concrete Structures ◽  
The Impact

This article presents results of a theoretical study of reinforced concrete beams with damaged reinforcement. The change of micro-hardness of a reinforcing rebar’s with a diameter of 20 mm of A500C steel in the radial direction is investigated and the thickness of the heat-strengthened layer is established. It is established that the thickness of the thermo-strengthened steel layer of the reinforcing bar with a diameter of 20 mm of A500C is approximately 3 mm. It is shown that the strength characteristics of this layer are on 50% higher compared to the core material of the rebar, while the plasticity characteristics are lower. The aim of the work is to determine the strength and deformability of reinforced concrete structures without damaging the reinforcement and in case of damage. Determining the impact of changes in the physical characteristics of reinforcement on the damage of reinforced concrete structures, according to the calculation to the valid norms, in accordance with the deformation model. To achieve the goal of the work, theoretical calculations of reinforced concrete beams were performed according to the deformation model, according to valid norms. This technique uses nonlinear strain diagrams of concrete and rebar and is based on an iterative method. According to the research program 3 beam samples were calculated. Among them were undamaged control sample with single load bearing reinforcement of ∅20 mm diameter – BC-1; sample with ∅20 mm reinforcement with damages about 40% without changes in the physical and mechanical properties of reinforcement – BD-2 and sample with ∅20 mm reinforcement with damages about 40% with changes in the physical and mechanical properties of reinforcement – BD-3. The influence of change of physical and mechanical characteristics of rebar’s on bearing capacity of the damaged reinforced concrete beams is established.

scholarly journals An Experimental Study of the Impact Mechanical Properties of RC Beams following Replacements of Stainless Steel Reinforcements of Equal Strength

2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Xiwu Zhou ◽  
Runcheng Zhang ◽  
Ruisheng Xiong ◽  
Guoxue Zhang ◽  
Xiangyu Wang
Keyword(s):  
Stainless Steel ◽  
Reinforced Concrete ◽  
Concrete Structure ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Reinforced Concrete Structure ◽  
Steel Reinforced Concrete ◽  
Equal Strength ◽  
Steel Bar ◽  
The Impact

The reinforced concrete structure of a port wharf is affected by steel corrosion and ship docking impact. Replacing an ordinary steel bar with a stainless steel bar can solve the corrosion problem of the steel bar while ensuring the bearing capacity of the structure. However, the research on impact resistance of stainless steel-reinforced concrete structure is not perfect. In this paper, impact mechanical properties of reinforced concrete beams before and after equal strength replacement of stainless steel bars are analyzed by theoretical analysis and drop hammer impact test, and the possibility and applicable scope of equal strength replacement of stainless steel bars are put forward. The results indicated the following: (1) when the reinforcement ratios were small (0.21% to 1.32%), the stainless steel-reinforced concrete beams with equal strength were able to effectively reduce the stiffness losses of the beams undergoing impact loads, as well as improve the elastic resilience abilities, and reduce the structural damages. Therefore, the corrosion and impact problems of reinforcements could be solved by replacing ordinary reinforcements with stainless steel reinforcements and (2) when the reinforcement ratios were large (1.32% to 2.57%), the shear failures of the stainless steel-reinforced concrete beams were observed to be relatively serious, and the impact resistance performances had worsened. The research results provide technical support for the engineering application of stainless steel-reinforced concrete structure design.

Research on the Mechanical Properties of Concrete Members under Holding Load

2011 ◽  
Vol 255-260 ◽  
pp. 309-313
Author(s):  
Li Hua Lu ◽  
Hai Xia Sun ◽  
Si Li Chen ◽  
Gui Sheng Pan ◽  
Min Ji Yang
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Concrete Structure ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
Reinforced Concrete Structure ◽  
Concrete Members ◽  
Practical Engineering

In order to study the bearing capacity conditions of the reinforced concrete structure in service in the phase of using,test the mechanical properties of the bending members of reinforced concrete structures under loading and not loading conditions,and compare and analyze the relationship of load and deflection, crack, steel strain,concrete face strain under the two conditions,has got the conclusion that the bearing capacity decreased almost 12% under holding load, and analyze the effect of the bearing capacity and deformation under holding load; use ABAQUS finite element to simulate bending members of reinforced concrete structures under holding loading,and the simulation values are very close to the experimental results; indicate that finite element simulation can be carried out in prediction the service life of reinforced concrete structure in practical engineering.

Finite Element Analysis of Reinforced Concrete Beams with Exterior FRP Shell

2011 ◽  
Vol 243-249 ◽  
pp. 1461-1465
Author(s):  
Chuan Min Zhang ◽  
Chao He Chen ◽  
Ye Fan Chen
Keyword(s):  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Reinforced Concrete ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Test Results ◽  
Contact Interface ◽  
Accurate Calculation ◽  
Element Analysis

The paper makes an analysis of the reinforced concrete beams with exterior FRP Shell in Finite Element, and compares it with the test results. The results show that, by means of this model, mechanical properties of reinforced concrete beams with exterior FRP shell can be predicted better. However, the larger the load, the larger deviation between calculated values and test values. Hence, if more accurate calculation is required, issues of contact interface between the reinforced concrete beams and the FRP shell should be taken into consideration.

scholarly journals Strengthening of Reinforced Concrete Beams Subjected to Concentrated Loads

2022 ◽  
Author(s):  
Paolo Foraboschi
Keyword(s):  
Reinforced Concrete ◽  
Carrying Capacity ◽  
Concrete Beams ◽  
Shear Capacity ◽  
Reinforced Concrete Beams ◽  
Load Carrying Capacity ◽  
Reinforced Concrete Structure ◽  
Concentrated Loads ◽  
Concentrated Load ◽  
Load Carrying

Renovation, restoration, remodeling, refurbishment, and retrofitting of build-ings often imply modifying the behavior of the structural system. Modification sometimes includes applying forces (i.e., concentrated loads) to beams that before were subjected to distributed loads only. For a reinforced concrete structure, the new condition causes a beam to bear a concentrated load with the crack pattern that was produced by the distributed loads that acted in the past. If the concentrated load is applied at or near the beam’s midspan, the new shear demand reaches the maximum around the midspan. But around the midspan, the cracks are vertical or quasi-vertical, and no inclined bar is present. So, the actual shear capacity around the midspan not only is low, but also can be substantially lower than the new demand. In order to bring the beam capacity up to the demand, fiber-reinforced-polymer composites can be used. This paper presents a design method to increase the concentrated load-carrying capacity of reinforced concrete beams whose load distribution has to be changed from distributed to concentrated, and an analytical model to pre-dict the concentrated load-carrying capacity of a beam in the strengthened state.

Study on Retrofitting and Strengthening of Reinforced Concrete Beams Using Fibrous Concrete

2021 ◽  
Vol 9 (8) ◽  
pp. 1676-1684
Author(s):  
Natalia Sharma
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Steel Fiber ◽  
Concrete Beams ◽  
Fiber Reinforced Concrete ◽  
Steel Fibers ◽  
Reinforced Concrete Beams ◽  
Cement Matrix ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete

Abstract: Reinforced concrete structures are frequently in need of repair and strengthening as a result of numerous environmental causes, ageing, or material damage under intense stress conditions, as well as mistakes made during the construction process. RC structures are repaired using a variety of approaches nowadays. The usage of FRC is one of the retrofitting strategies. Steel fiber reinforced concrete (SFRC) was used in this investigation because it contains randomly dispersed short discrete steel fibers that operate as internal reinforcement to improve the cementitious composite's characteristics (concrete). The main rationale for integrating small discrete fibers into a cement matrix is to reduce the amount of cement used. The principal reason for incorporating short discrete fibers into a cement matrix is to reduce cracking in the elastic range, increase the tensile strength and deformation capacity and increase the toughness of the resultant composite. These properties of SFRC primarily depend upon length and volume of Steel fibers used in the concrete mixture. In India, the steel fiber reinforced concrete (SFRC) has seen limited applications in several structures due to the lack of awareness, design guidelines and construction specifications. Therefore, there is a need to develop information on the role of steel fibers in the concrete mixture. The experimental work reported in this study includes the mechanical properties of concrete at different volume fractions of steel fibers. These mechanical properties include compressive strength, split tensile strength and flexural strength and to study the effect of volume fraction and aspect ratio of steel fibers on these mechanical properties. However, main aim of the study was significance of reinforced concrete beams strengthened with fiber reinforced concrete layer and to investigate how these beams deflect under strain. The objective of the investigation was finding that applying FRC to strengthen beams enhanced structural performance in terms of ultimate load carrying capacity, fracture pattern deflection, and mode of failure or not.

scholarly journals Seismic Behaviors of Concrete Beams Reinforced with Steel-FRP Composite Bars under Quasi-Static Loading

2018 ◽  
Vol 8 (10) ◽  
pp. 1913 ◽  
Author(s):  
Tong-Liang Xiao ◽  
Hong-Xing Qiu ◽  
Jia-Le Li
Keyword(s):  
Reinforced Concrete ◽  
Seismic Performance ◽  
Concrete Beams ◽  
Concrete Strength ◽  
Reinforced Concrete Beams ◽  
Ultimate Capacity ◽  
Shear Span ◽  
Frp Composite ◽  
Drift Ratio ◽  
Seismic Behaviors

Steel-fiber reinforced polymer (FRP) composite bar (SFCB) is a new composite material with good corrosion resistance and designable post-yield stiffness. Substitution of steel bar with SFCB can greatly increase the durability and ultimate capacity associated with seismic performance. First, the method and main results of the experiment are briefly introduced, then a simplified constitutive model of composite bar material was applied to simulate the seismic behaviors of the concrete beams reinforced with SFCBs by fiber element modeling. The simulation results were found to be in good agreement with test results, indicating that the finite element model is reasonable and accurate in simulating the seismic behaviors of beams reinforced with SFCB. Based on the numerical simulation method, a parametric study was then conducted. The main variable parameters were the FRP type in composite bars (i.e., basalt, carbon FRP and E-glass FRP), the concrete strength, basalt FRP (BFRP) content in SFCBs and shear span ratio. Seismic behaviors such as load-displacement pushover curves, seismic ultimate capacity and its corresponding drift ratio of the SFCBs reinforced concrete beams were also evaluated. The results showed that (1) the fiber type of the composite bar had a great impact on the mechanical properties of the beam, among which the beam reinforced with BFRP composite bar has higher seismic ultimate capacity and better ductility. With the increase of the fiber bundle in the composite bar, the post-yield stiffness and ultimate capacity of the component increase and the ductility is better; (2) at the pre-yield stage, concrete strength has little influence on the seismic performance of concrete beams while after yielding, the seismic ultimate capacity and post-yielding stiffness of specimens increased slowly with the increase in concrete strength, however, the ductility was reduced accordingly; (3) as the shear span ratio of beams increased from 3.5 to 5.5, the seismic ultimate capacity decreased gradually while the ultimate drift ratio increased by more than 50%. Through judicious setting of the fiber content and shear span ratio of the composite bar reinforced concrete beam, concrete beams reinforced with composite bars can have good ductility while maintaining high seismic ultimate capacity.

scholarly journals Modeling Blast Loading on Buried Reinforced Concrete Structures with Zapotec

2008 ◽  
Vol 15 (2) ◽  
pp. 137-146 ◽  
Author(s):  
Greg C. Bessette
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structure ◽  
Explosive Charge ◽  
High Explosive ◽  
Concrete Structures ◽  
Blast Loading ◽  
Reinforced Concrete Structures ◽  
Reinforced Concrete Structure ◽  
Solution Approach ◽  
Coupling Algorithm

A coupled Euler-Lagrange solution approach is used to model the response of a buried reinforced concrete structure subjected to a close-in detonation of a high explosive charge. The coupling algorithm is discussed along with a set of benchmark calculations involving detonations in clay and sand.

Non-Destructive Vibration Tests on Reinforced Concrete Structures

2015 ◽  
Vol 660 ◽  
pp. 186-191 ◽  
Author(s):  
Marina Lute
Keyword(s):  
Reinforced Concrete ◽  
Dynamic Response ◽  
Concrete Beams ◽  
Concrete Structures ◽  
Reinforced Concrete Beams ◽  
Reinforced Concrete Structures ◽  
Linear Behavior ◽  
Non Linear ◽  
Vibration Tests ◽  
Non Destructive

The purpose of this paper is looking at the dynamic response of existing reinforced concrete structures which have possibly sustained various levels of damage, a set of tests need to be identified that will be able to detect damage and quantify the damage if damage exists. In this work it is presented a further study on the effect of damage on the behavior of reinforced concrete beams. In particular, the non-linear behavior of these beams is considered once significant cracking has been introduced, outlining the stage of testing carried out in dynamic field.

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