Behavior of High Strength Hybrid Reinforcement Concrete Beams

2020 ◽  
Vol 12 (7) ◽  
Author(s):  
Khanda Ali Al-Billbassi ◽  
◽  
Mushriq Fuad Kadhim Al-Shamaa ◽  
Keyword(s):  
Residual Strength ◽  
Ultimate Load ◽  
Steel Fiber ◽  
Load Capacity ◽  
High Strength ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Ultimate Load Capacity ◽  
Cross Sectional ◽  
Sectional Shape

Six proposed simply supported high strength-steel fiber reinforced concrete (HS-SFRC) beams reinforced with FRP (fiber reinforced polymer) rebars were numerically tested by finite element method using ABAQUS software to investigate their behavior under the flexural failure. The beams were divided into two groups depending on their cross sectional shape. Group A consisted of four trapezoidal beams with dimensions of (height 200 mm, top width 250 mm, and bottom width 125 mm), while group B consisted of two rectangular beams with dimensions of (125 ×200) mm. All specimens have same total length of 1500 mm, and they were also considered to be made of same high strength concrete designed material with 1% volume fraction of steel fiber. Different types and ratios of FRP rebar were used to reinforce these test beams. The study’s principle variables were the amount and type of flexural reinforcement (glass FRP and basalt FRP) and beam cross-sectional shape (rectangular and trapezoidal). The load-deflection behavior and ultimate load capacity of the beams were studied and compared with one another under flexural test with symmetrical two-point loading. The results show that increasing the reinforcement ratio resulted in higher post cracking flexural stiffness, and higher residual strength, as well as caused an increase in the first cracking load and ultimate load capacity ranged from 3 to 16.9%, and 4.6 to 7.3% respectively. When the GFRP rebars replaced by BFRP, the overall beams flexural performance showed outstanding improvements. Moreover the results indicate that increasing the top width of the beam cross section led to a significant enhancement in the first crack load ranged from 16 to 32.4%, also a remarkable increases in the ultimate load capacity in the range of 35.5 to 35.8% were indicated in the trapezoidal beams compared to rectangular beams. However the results show that the deflections were similar and were approximately 1.07–1.54 mm for all test beams. It is worth noting that the general flexural behavior of all the test beams indicated a ductile behavior with a gradual reduction in strength and high residual strength pre to failure due to proposing steel fiber presence.

Behaviour of Concrete Filled Steel Square-Tube Stub Column with Steel-Fiber Reinforced High Strength Concrete

2013 ◽  
Vol 663 ◽  
pp. 125-129 ◽  
Author(s):  
Chang Sik Choi ◽  
Hyung Suk Jung ◽  
Hyun Ki Choi
Keyword(s):  
High Strength Concrete ◽  
Steel Fiber ◽  
Load Capacity ◽  
Compressive Load ◽  
High Strength ◽  
Steel Tube ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Strength Concrete ◽  
Stub Columns

The paper presents an experimental study on the behavior of axial loaded concrete-filled steel square-tube stub columns with high strength fiber reinforced concrete until failure. Four specimens were tested to investigate the effect of high strength concrete on the load carrying capacity of the concrete-filled steel square-tube stub columns. The effect of the presence of steel fiber in high strength concrete which filled in the steel tube was also investigated. The main parameters in the tests were: (1) the strength of concrete (30 Mpa and 100 Mpa), and (2) the use of reinforcing steel fiber in concrete (plain high strength concrete and steel fiber high strength concrete). The main purpose of these tests were three-step: (1) to describe a series of tests on composite stub columns, (2) to analyze the influence of several parameters, and (3) to compare the accuracy of the predictions by using the specifications in the code (ACI and EC4 etc.) for the design of high-strength composite columns. Experimental results indicate that the high strength of concrete and use of steel-fiber in concrete had significant influence on both the axial compressive load capacity and the ductile of the steel square-tube stub columns.

scholarly journals Experimental Study on Shear Behavior of Steel Fiber Reinforced Concrete Beams with High-Strength Reinforcement

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1682 ◽  
Author(s):  
Jun Zhao ◽  
Jingchao Liang ◽  
Liusheng Chu ◽  
Fuqiang Shen
Keyword(s):  
Reinforced Concrete ◽  
Crack Width ◽  
Steel Fiber ◽  
High Strength ◽  
Shear Behavior ◽  
Fiber Reinforced Concrete ◽  
Reinforced Concrete Beams ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Diagonal Crack

Many researchers have performed experimental and theoretical studies on the shear behavior of steel fiber reinforced concrete (SFRC) beams with conventional reinforcement; few studies involve the shear behavior of SFRC beams with high-strength reinforcement. In this paper, the shear test of eleven beams with high-strength reinforcement was carried out, including eight SFRC beams and three reinforced concrete (RC) beams. The load-deflection curve, concrete strain, stirrup strain, diagonal crack width, failure mode and shear bearing capacity of the beams were investigated. The test results show that steel fiber increases the stiffness, ultimate load and failure deformation of the beams, but the increase effect of steel fiber decreases with the increase of stirrup ratio. After the diagonal crack appears, steel fiber reduces the concrete strains of the diagonal section, stirrup strains and diagonal crack width. In addition, steel fiber reduces crack height and increases crack number. Finally, the experimental values of the shear capacities were compared with the values calculated by CECS38:2004 and ACI544.4R, and the equation of shear capacity in CECS38:2004 was modified to effectively predict the shear capacities of SFRC beams with high-strength reinforcement.

Ultimate Load Capacity of Spot Welds Made of Ultra High Strength Steels

2011 ◽  
Author(s):  
Zongfen Zhang ◽  
Chris Chen ◽  
Gregory Zywicki ◽  
Brad Blaski ◽  
James Blenman
Keyword(s):  
Ultimate Load ◽  
Load Capacity ◽  
High Strength Steels ◽  
High Strength ◽  
Spot Welds ◽  
Ultimate Load Capacity ◽  
Ultra High Strength Steels

scholarly journals The Behavior of a Strengthened Steel Beam Section Under Eccentric Loadings

2021 ◽  
Vol 318 ◽  
pp. 03007
Author(s):  
Mohammed M. Rasheed ◽  
Kamal Sh. Mahmoud ◽  
Saad Khalaf Mohaisen ◽  
Mohammed Z. Yousif
Keyword(s):  
Ultimate Load ◽  
Load Capacity ◽  
The Other ◽  
Steel Beams ◽  
Steel Beam ◽  
Ultimate Load Capacity ◽  
Cross Sectional ◽  
External Prestressing ◽  
Beam Section ◽  
Prestressing Strand

Thirteen simply supported steel samples have been tested to explain the effects of strengthening steel beams using an external prestressing strand. The samples have the same cross-sectional dimensions and overall length. One steel beam without strengthening was taken as a reference, while the other twelve of them had been strengthening by two external strands at various eccentricity locations and jacking stresses. The strengthening by external prestressing strands is sub-divided into two series according to jacking stress. Each series consists of six steel samples divided according to the eccentricity location of prestressing strand. During tests, it was found that the Load deflection response for the strengthened samples is stiffer as compared with the reference. The increasing percentage in ultimate load capacity was increased to 0.347, 2.758, 3.921, 8.898, 9.326, and 10.256% for beams under jacking stress of 1120 MPa, while increasing percentage in ultimate load capacity were increased to 0.17, 26, 33, 48.5, 13.7, and 69.56% for beams under jacking stress of 815 MPa. On the other hand, the maximum percentages of deflection were decreased to 4.88, 2.44, 20.62, 15, and 9.7% when the jacking stress increase from 815 to 1120 MPa and the ratio of the quarter to mid-span deflection (δ quarter / δ mid) is about 0.528 and 0.497 when jacking stress is 1120 and 815 MPa respectively. So, the increase in jacking stresses from 815 to 1120 MPa will not be preferable because it has a little increasing percentage in stiffening and behaviors compared with other tested beams at the same condition.

scholarly journals The change in impermeability of steel fiber reinforced concrete with high strength cement-sand matrix at heating

2020 ◽  
Vol 17 (1) ◽  
pp. 150-155
Author(s):  
V. A. Dorf ◽  
◽  
R. O. Krasnovskij ◽  
D. E. Kapustin ◽  
P. S. Sultygova ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Steel Fiber ◽  
Heating Temperature ◽  
High Strength ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Fiber Concrete ◽  
The Matrix ◽  
Steel Fiber Concrete

The paper considers the effects of high temperatures in case of fire on the change in impermeability of steel fiber reinforced concrete having a high-strength cement-sand matrix and various content of fiber of different types, sizes, and strength. It is shown that in the temperature range from 20° to 1100° C in the diagram “Heating temperature - impermeability class», the matrix and steel fiber concrete(SFC) have a S-shaped character, and in case of heating temperature of over 100 °C, there comes a distinct decrease in impermeability.

scholarly journals Optimization of the Fine to Coarse Aggregate Ratio for the Workability and Mechanical Properties of High Strength Steel Fiber Reinforced Concretes

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5202
Author(s):  
Mohammad Iqbal Khan ◽  
Wasim Abbass ◽  
Mohammad Alrubaidi ◽  
Fahad K. Alqahtani
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Flexural Strength ◽  
Coarse Aggregate ◽  
Steel Fiber ◽  
High Strength ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Fresh State

High-strength concrete is used to provide quality control for concrete structures, yet it has the drawback of brittleness. The inclusion of fibers improves the ductility of concrete but negatively affects the fresh properties of fiber-reinforced concrete. The effects of different fine to coarse aggregate ratios on the fresh and hardened properties of steel fiber reinforced concrete were investigated in this study. Mixtures were prepared with various fine to coarse aggregate (FA/CA) ratios incorporating 1% steel fiber content (by volume) at constant water to cement ratio. The workability, unit weight, and temperature of the concrete in the fresh state, and the mechanical properties of steel-fiber-reinforced concrete (SFRC) were investigated. The inclusion of fiber in concrete influenced the mobility of concrete in the fresh state by acting as a barrier to the movement of coarse aggregate. It was observed that the concrete with an FA/CA ratio above 0.8 showed better flowability in the fresh state, whilst an above 0.9 FA/CA ratio requires excessive superplasticizer to maintain the flowability of the mixtures. The compressive and flexural strength of SFRC increased with an increase in the FA/CA ratio by around 10% and 28%, respectively. Experimental values of compressive strength and flexural strength showed good agreement, however, modulus of elasticity demonstrated slightly higher values. The experimentally obtained measurements of the mechanical properties of SFRC conformed reasonably well with the available existing prediction equations, and further enabled establishing predictive isoresponse interactive equations within the scope of the investigation domain.

Sign in / Sign up

Export Citation Format

Share Document