Data-driven shear strength prediction of steel fiber reinforced concrete beams using machine learning approach

Shear strength of steel fiber-unconfined reinforced concrete beam simulation: Application of novel intelligent model

Even though the structural behavior steel fiber reinforced concrete (SFRC) has been extensively researched, structural applications are still limited. One barrier to its implementation is the lack of mechanical models that describe the behaviour of SFRC members failing in shear. This paper reviews the effect of steel fibers on the different mechanisms of shear transfer and combines the observations from the literature regarding the parameters that affect the shear capacity of SFRC. Additionally, a selection of currently available expressions for the shear capacity of SFRC is presented. This paper reviews the current state-of-the-art on the shear capacity of SFRC elements without shear reinforcement, shows the lacks in our current understanding on the shear behaviour of SFRC elements without shear reinforcement, and outlines the steps necessary to address these lacks. The presented work aims to be a framework for (experimental) efforts addressing the shear capacity of SFRC members without shear reinforcement.

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How do steel fibers improve the shear capacity of reinforced concrete beams without stirrups

One of the primary concerns about the design aspects is that how to deal with the shear reinforcement in the ultra-high performance fiber reinforced concrete (UHPFRC) beam. This study aims to investigate the shear behavior of UHPFRC rectangular cross sectional beams with fiber volume fraction of 1.5 % considering a spacing of shear reinforcement. Shear tests for simply supported UHPFRC beams were performed. Test results showed that the steel fibers substantially improved of the shear resistance of the UHPFRC beams. Also, shear reinforcement had a synergetic effect on enhancement of ductility. Even though the spacing of shear reinforcement exceeds the spacing limit recommended by current design codes (ACI 318-14), shear strength of UHPFRC beam was noticeably greater than current design codes. Therefore, the spacing limit of 0.75d can be allowed for UHPFRC beams.

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Shear Tests for Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) Beams with Shear Reinforcement

https://repositorium.sdum.uminho.pt/bitstream/1822/19793/1/manuscript.pdf

Shear behaviour of steel fibre reinforced self-consolidating concrete beams based on the modified compression field theory

This study analyzed the mechanical behavior of shear strength of steel fiber-reinforced concrete beams. Six beams subjected to shear loading were tested until failure. Additionally, prisms were tested to evaluate fiber contribution to the concrete shear strength. Steel fibers were straight, hook-ended, 35 mm long and aspect ratio equal to 65. Volumetric fractions used were 1.0 and 2.0%. The results demonstrated a great contribution from steel fibers to shear strength of reinforced concrete beams and to reduce crack width, which can reduce the amount of stirrups in reinforced concrete structures. Beam capacity was also evaluated by empirical equations, and it was found that these equations provided a high variability, while some of them have not properly predicted the ultimate shear strength of the steel fiber-reinforced concrete beams.

Shear strength of steel fiber-reinforced concrete beams

In this paper, the mechanical behavior of steel-fiber-reinforced concrete was investigated to analyze the influence of steel fibers on tension stiffening. Using tension tests, the tension stiffening coefficient was evaluated through the load versus strain responses obtained from strain gages fixed to reinforcement steels. Moreover, an empirical model is proposed to estimate the tension stiffening coefficient of steel-fiber-reinforced concrete from reinforcement strains. From the test results, it was verified that the addition of steel fibers to concrete reduced the reinforcement steel strains and the crack width and increased the stiffness of cracked concrete, mainly in concretes reinforced with highvolumesof fibers.

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Tension stiffening of steel-fiber-reinforced concrete

A new comprehensive framework for the analysis of mass concrete: Thermo-chemo-mechanical, experimental, numerical and data modeling

Polymeric Admixtures as Bonding Agent between Tire Rubber and Concrete Matrix

Resumo In this work the influence of steel fibers and mineral additions (silica fume and fly-ash) on cracking behavior of reinforced concrete tension members was investigated. Hooked-end steel fibers with aspect ratio of 65 were used in volumes of 0.75%, 1.00% e 1.50%. Sixteen tension tests were performed in tension members 800 mm long with square cross section of 150 mm of side reinforced with single bar of CA-50 steel with diameter of 20 mm for determining crack widths. The results showed that steel fibers reduced the average crack width up to 75% and mineral additions improved cracking behavior of concrete. Crack widths were compared with suggested values by Brazilian, American and European recommendations, which were unsuitable for estimating crack width in steel fiber reinforced concrete.

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Influence of steel fibers and mineral additions on cracking behavior of reinforced concrete tension members Influência das fibras de aço e das adições minerais na fissuração de tirantes de concreto armado

M.A.S. Andrade

Papers

Shear strength of steel fiber-reinforced concrete beams

Tension stiffening of steel-fiber-reinforced concrete

A new comprehensive framework for the analysis of mass concrete: Thermo-chemo-mechanical, experimental, numerical and data modeling

Polymeric Admixtures as Bonding Agent between Tire Rubber and Concrete Matrix

Influence of steel fibers and mineral additions on cracking behavior of reinforced concrete tension members Influência das fibras de aço e das adições minerais na fissuração de tirantes de concreto armado