Experimental Study of Section Enlargement with Reinforced Concrete to Increase Shear Capacity for Damaged Reinforced Concrete Beams

2012 ◽  
Vol 256-259 ◽  
pp. 1148-1153 ◽  
Author(s):  
Yuan Dong Wang ◽  
Shen Yang ◽  
Miao Han ◽  
Xun Yang
Keyword(s):  
Reinforced Concrete ◽  
Epoxy Resin ◽  
Cross Section ◽  
Load Capacity ◽  
Shear Capacity ◽  
Reinforced Concrete Beams ◽  
Second Phase ◽  
Ultimate Shear Strength ◽  
Ultimate Load Capacity ◽  
External Reinforcement

This paper presents the results of reinforced concrete (RC) beams strengthened in shear by external reinforcement with RC or epoxy resin mortar. The test specimen was 2000mm long with a cross section of 150mm×200mm and after section enlargement the cross section was increased to 250mm×300mm, in addition, shear span to beam depth ratio of a/h0 was 2.35. All specimens had the same geometry and were distinguished by the configurations of stirrup which was the primary test variable. No shear reinforcement was provided in the first phase of test, while in the second phase external RC or epoxy resin mortar was provided to enable failure due to shear. Experiments are undertaken to investigate the influence of preexisting damage, configurations of stirrup and different methods on the strengthened behavior and mode of failure. A group unstrengthened control beams were tested and failed in shear. In contrast to the control beam, all of the strengthened beams showed a significant improvement in their ultimate load capacity when they were failing in shear. The enlarged section with reinforced concrete can significantly increase the ductility and ultimate shear strength of a concrete beam. The method of section enlargement with RC is a high effective technique to enhance shear ability. An analysis for shear strengthening of beams using external reinforcement with RC has also been carried out as well.

Performance of Reinforced Concrete Beams with Multiple Openings

2020 ◽  
Vol 857 ◽  
pp. 162-168
Author(s):  
Haidar Abdul Wahid Khalaf ◽  
Amer Farouk Izzet
Keyword(s):  
Reinforced Concrete ◽  
Ultimate Load ◽  
Concrete Beams ◽  
Load Capacity ◽  
Reinforced Concrete Beams ◽  
Design Parameters ◽  
Ultimate Load Capacity ◽  
Concentrated Load ◽  
Simply Supported ◽  
Group I

The present investigation focuses on the response of simply supported reinforced concrete rectangular-section beams with multiple openings of different sizes, numbers, and geometrical configurations. The advantages of the reinforcement concrete beams with multiple opening are mainly, practical benefit including decreasing the floor heights due to passage of the utilities through the beam rather than the passage beneath it, and constructional benefit that includes the reduction of the self-weight of structure resulting due to the reduction of the dead load that achieves economic design. To optimize beam self-weight with its ultimate resistance capacity, ten reinforced concrete beams having a length, width, and depth of 2700, 100, and 400 mm, respectively were fabricated and tested as simply supported beams under one incremental concentrated load at mid-span until failure. The design parameters were the configuration and size of openings. Three main groups categorized experimental beams comprise the same area of openings and steel reinforcement details but differ in configurations. Three different shapes of openings were considered, mainly, rectangular, parallelogram, and circular. The experimental results indicate that, the beams with circular openings more efficient than the other configurations in ultimate load capacity and beams stiffness whereas, the beams with parallelogram openings were better than the beams with rectangular openings. Commonly, it was observed that the reduction in ultimate load capacity, for beams of group I, II, and III compared to the reference solid beam ranged between (75 to 93%), (65 to 93%), and (70 to 79%) respectively.

Experimental Study on Reinforcement of Failure Reinforced Concrete Beams

2013 ◽  
Vol 275-277 ◽  
pp. 1264-1267
Author(s):  
Qian Chen ◽  
Ling Yong Liu ◽  
Yang Jun Meng
Keyword(s):  
Experimental Study ◽  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Epoxy Resin ◽  
Cross Section ◽  
Concrete Beams ◽  
Experimental Results ◽  
Reinforced Concrete Beams ◽  
Carbon Cloth ◽  
Structural Failure

Through repair and reinforcement of breaking reinforced concrete beams by epoxy resin and carbon cloth, and its experiment, the crack and deformation and bearing capacity as well as ductility of such beams are obtained. Experimental results show that the ultimate bearing capacity of beams after reinforcement increased by 210%, the structure ductility fell by 170%, structural failure form is similar to failure in normal cross section.

The Behavior of Reinforced and Pre-Stressed Concrete Beams under Elevated Temperature

2020 ◽  
Vol 47 ◽  
pp. 15-30
Author(s):  
Amr H. Badawy ◽  
Ahmed Hassan ◽  
Hala El-Kady ◽  
L.M. Abd-El Hafez
Keyword(s):  
Reinforced Concrete ◽  
Elevated Temperature ◽  
Prestressed Concrete ◽  
Mechanical Performance ◽  
Concrete Beams ◽  
Load Capacity ◽  
Reinforced Concrete Beams ◽  
Flexural Behavior ◽  
Second Phase ◽  
Prestressed Beam

The behavior of unbounded post tension and reinforced concrete beams under elevated temperature was presented. The experimental work was consisted of two major phases. In the first phase, the objective was studying the mechanical performance of prestressed beam, prestressed beam with steel addition and reinforced concrete beams respectively were studied. In the second phase, the residual mechanical performance of prestressed beam, prestressed beam with steel addition and reinforced concrete beams under elevated 400oC, for 120 minutes durations. The failure mechanisms, ultimate load capacity, and deflection at critical sections were monitored. The numerical prediction of the flexural behavior of the tested specimens is presented in this paper. This includes a comparison between the numerical and experimental test results according to ANSYS models. The results indicate that the prestressed beam with steel addition and reinforced concrete beams had higher resistance to beams under elevated 400oC than that of prestressed concrete beam in terms of ultimate capacity. It is also shown that the reinforced concrete beams have higher resistance to beams under elevated temperature than that of prestressed beam, prestressed beam with steel addition.

scholarly journals Experimental analysis of eccentrically loaded reinforced concrete columns with an added jacket of self-compacting concrete

2019 ◽  
Vol 12 (2) ◽  
pp. 329-336
Author(s):  
J. P. VIRGENS ◽  
R. B. GOMES ◽  
L. M. TRAUTWEIN ◽  
G. N. GUIMARÃES ◽  
A. P. R. VAZ
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Ultimate Load ◽  
Load Capacity ◽  
Concrete Columns ◽  
Reinforce Concrete ◽  
Self Compacting Concrete ◽  
Ultimate Load Capacity ◽  
Reinforced Concrete Columns ◽  
Concrete Layer

Abstract This paper presents the experimental study of eccentrically loaded reinforced concrete columns with an added 35 mm self-compacting concrete jacket attached to the column’s most compressed face using wedge bolts. Nine columns with a 2000 mm height were tested under compression and one-way bending until failure. Columns were denominated as original column (PO) with a cross section of 120 mm x 250 mm; reference column (PR) with a cross section of 155 mm x 250 mm, and seven columns with an initial cross section of 120 mm x 250 mm and later reinforced by the addition of 35 mm self-compacting concrete layer and various configurations of wedge bolts. Except for the original column PO, the columns were submitted to a 42.5 mm load eccentricity due to the added concrete layer at the compressed face. Although failure of the wedge bolts did not occur, it was not possible to prevent detachment of the added layer. The results indicate that it is possible to structurally rehabilitate reinforce concrete columns with the use of the strengthening methodology used in this research, resulting in average ultimate load capacity gains of 271% compared to original column’s ultimate load.

Experimental Study of Corroded RC Beams Strengthened with CFRP under Fatigue and Monotonic Loads

2011 ◽  
Vol 243-249 ◽  
pp. 142-148
Author(s):  
Lei Wang ◽  
Jin Xiu Liang
Keyword(s):  
Experimental Study ◽  
Reinforced Concrete ◽  
Composite Laminates ◽  
Load Capacity ◽  
Experimental Studies ◽  
Corrosion Damage ◽  
Fatigue Loading ◽  
Reinforced Concrete Beams ◽  
Ultimate Load Capacity ◽  
Cfrp Composite

This paper summarizes the results and discussion of experimental studies on corroded, reinforced concrete 4 point beam test specimens (120 mm x 200 mm x 1700 mm) repaired by external bonding of carbon fiber reinforced polymer (CFRP) composite laminates to the tensile face of the beam. The primary parameters investigated in this experimental study were distortion, stress distribution, and ultimate load capacity of the corroded reinforced concrete beams. The results indicate that the load capacity and the rigidity of repaired corroded beams by CFRP were significantly higher than the un-repaired, corroded beams. Beams with a low degree of corrosion damage, repaired by CFRP, were still able to demonstrate good mechanical properties after a short-term fatigue loading.

Shear Capacity of Reinforced Concrete Beams under Biaxial Bending Based on Equivalent Cross-Section Method

2008 ◽  
Vol 400-402 ◽  
pp. 275-280
Author(s):  
Qing Xiang Zeng ◽  
Jian Cai
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Concrete Beams ◽  
Shear Capacity ◽  
Reinforced Concrete Beams ◽  
Biaxial Bending ◽  
Section Method ◽  
Flexural Member ◽  
Flexural Beam ◽  
Cross Section Method

Based on the analysis of reinforced concrete beams under biaxial bending, an equivalent cross-section method is proposed to calculate the shear capacity of the beams. According to the two basic equivalence principles, a biaxial flexural beam is changed into a uniaxial flexural member, and the shear strength of biaxial flexural beam is calculated as a uniaxial flexural member. Furthermore, the interrelationships among the equivalent cross-section and the neutral axis inclination as well as the ratio of depth to width of the cross-section are deduced in advance. The ratios of some typical cross-section’s equivalent dimensions to its original ones are pointed also. In order to verify the availability of the equivalent cross-section method, some academic references about the ultimate strength of biaxial flexural beams are consulted in this paper, and the shear capacity computing methods by literatures for uniaxial flexural beams are adopted in the strength calculation of biaxial flexural reinforced concrete simply supported beams with stirrups or without stirrups. The comparison between the calculation results and experimental results shows that the presented equivalent cross-section method is feasible and practical which can be used as a reference in practice design.

Shear Strengthening of Reinforced Concrete Beams with HFRP Composite

2016 ◽  
Vol 860 ◽  
pp. 152-155
Author(s):  
Sanyawit Siriluk ◽  
Qudeer Hussain ◽  
Winyu Rattanapitikon ◽  
Amorn Pimanmas
Keyword(s):  
Reinforced Concrete ◽  
Ultimate Load ◽  
Natural Fiber ◽  
Load Capacity ◽  
Reinforced Concrete Beams ◽  
Deep Beam ◽  
Fiber Layer ◽  
Ultimate Load Capacity ◽  
Shear Strengthening ◽  
Hemp Fiber

This paper presents an experimental study on the strengthening of scaled reinforced concrete (RC) deep beam using hemp fiber reinforced polymer (HFRP) composite. HFRP is the composite material which compose of hemp fiber bonding with epoxy resin. The major benefit of using hemp fiber is that their low price, high toughness, and hemp is natural fiber product which that can be found locally. In this study 2 different fiber orientation has been apply to scaled deep beam and also different in thickness (fiber layer). Three scaled deep beam were strengthened using HFRP composite, remaining one beam was tested as control (unstrengthen) beam. The test result show that HFRP composite are effective to enhance ultimate load capacity for RC beam. The HFRP composite applied in U-Shape was result into higher ultimate load compare with the sample that applied with both side strengthen method

scholarly journals Shear Strengthening of Composite Steel-Concrete Girders with Web Openings Using CFRP Sheets

2018 ◽  
Vol 7 (4.20) ◽  
pp. 443
Author(s):  
Wael Shawky AbdulSahib ◽  
Mohammed J. Hamood ◽  
Ahmed Mohammed Majeed
Keyword(s):  
Ultimate Load ◽  
Concrete Slab ◽  
Load Capacity ◽  
Point Load ◽  
Shear Capacity ◽  
Ultimate Shear Strength ◽  
Ultimate Load Capacity ◽  
Web Openings ◽  
Concrete Girders ◽  
Composite Steel

This study presents an experimental investigation of subjecting one-point load at mid-span of five composite steel-concrete girders that are loaded predominantly in shear. Three of girders are reference girders with no web openings, square web openings, and circular web openings, respectively. The both other girders are strengthened girders. The compressive strength of concrete, slab reinforcement and all dimensions of girders are kept. The CFRP laminates were adhesively attached to the webs of strengthened girders in various patterns and were done to estimate the effect of strengthening scheme by CFRP composite on increasing of the ultimate load capacity of the web openings girders. The research purposes to examine the behavior and effect of increasing in the ultimate shear capacity of strengthened girders that have constant dimensions and locations of web openings which is about 40 % of web depth. The results show the increase in ultimate load capacity of strengthened girders containing square and circular web openings with about 23.75% and 25.9%, respectively compared to that of reference girders. Furthermore, the ultimate shear strength was predicted by von Mises stresses were used for girders without and with square and circular web openings.  

Sign in / Sign up

Export Citation Format

Share Document