Simplified prediction of the time dependent deflection of SFRC flexural members

Watts, Murray; Amin, Ali; Gilbert, Raymond Ian; Kaufmann, Walter; Minelli, Fausto

doi:10.1617/s11527-020-01479-8

Cited by 8 publications

(8 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several factors affect the behavior of structural concrete at the serviceability limit state. These include tension stiffening, cracking of the tensile concrete, and time‐dependent deformations which are induced by creep and shrinkage of the concrete 16,20 . With respect to tension stiffening, it is important to note that when the concrete in a cracked reinforced member shrinks by an amount ε sh over a time period Δ t , additional tensile stresses are induced within the concrete between the primary cracks due to the restraint provided by the reinforcement.…”

Section: Simplified Flexural Response Of Frc Beamsmentioning

confidence: 99%

“…The total curvature of a cracked FRC section at a particular point in time is a function of the extent of loading, and its geometric and material properties. For a section subjected to a moment M a (with M a > M cr ), the total curvature can be evaluated as:

κ ((), t) = M_{a} / ((), E_{c} I_{cr}) - κ_{t, TS} + κ_{cr} ((), t) + κ_{sh} ((), t)

We note that Equation () (excluding the tension stiffening offset parameter) also formed the basis of the model developed by Watts et al 20 in the determination of long‐term deformations in FRC members.…”

Section: Simplified Flexural Response Of Frc Beamsmentioning

confidence: 99%

See 1 more Smart Citation

Simplified time‐dependent crack width prediction for fiber reinforced concrete flexural members

Watts

Amin

Gilbert

et al. 2021

Structural Concrete

Self Cite

View full text Add to dashboard Cite

One of the main areas where it is generally accepted that fibers play a significant contribution in construction practice is in the control of cracking. The primary objective of the fibers is to traverse cracks after they nucleate. The fibers provide some post‐cracking resistance to the otherwise brittle concrete. Much of the research contained in the literature on the cracking behavior of fiber reinforced concrete (FRC) members has focused on instantaneous load scenarios, without much consideration for the long‐term behavior (i.e., for members which are subjected to a sustained service moment). This is mirrored in design standards where limited guidance is provided to engineers to predict and assess the long‐term serviceability performance of FRC members. This paper presents a simplified model, which may be suitable for design, that can reliably predict the cracking behavior, over time, of FRC members subjected to a sustained in‐service flexural load. Predictions of the proposed model are compared to both instantaneous and long‐term data available in the literature. Satisfactory correlation is observed.

show abstract

Section: Simplified Flexural Response Of Frc Beamsmentioning

confidence: 99%

κ ((), t) = M_{a} / ((), E_{c} I_{cr}) - κ_{t, TS} + κ_{cr} ((), t) + κ_{sh} ((), t)

Section: Simplified Flexural Response Of Frc Beamsmentioning

confidence: 99%

Simplified time‐dependent crack width prediction for fiber reinforced concrete flexural members

Watts

Amin

Gilbert

et al. 2021

Structural Concrete

Self Cite

View full text Add to dashboard Cite

show abstract

“…So far, most work on SLS constitutive modeling and design of SFRC has been undertaken in a sequence of papers by Amin and Gilbert [ 44 , 84 ], Amin et al [ 102 , 103 ], and Watts et al [ 86 , 87 ]. The authors started by developing a model for the tension stiffening effect in R-SFRC [ 102 ] and then succeeded in applying the model in the calculation of instantaneous crack widths [ 84 ] and instantaneous and time-dependent deflections [ 87 , 103 ].…”

Section: Research On the Structural Levelmentioning

confidence: 99%

“…The method was successfully verified using available experimental data. Watts et al [ 87 ] further applied this model to time-dependent deflections of R-SFRC members. The model is based on Equation (7) and the previous study by Amin et al [ 103 ], expanded by accounting for the increases in curvature over time due to creep (only compressive creep is considered) and shrinkage.…”

Section: Research On the Structural Levelmentioning

confidence: 99%

Systematic Review on the Creep of Fiber-Reinforced Concrete

2020

View full text Add to dashboard Cite

Fiber-reinforced concrete (FRC) is increasingly used in structural applications owing to its benefits in terms of toughness, durability, ductility, construction cost and time. However, research on the creep behavior of FRC has not kept pace with other areas such as short-term properties. Therefore, this study aims to present a comprehensive and critical review of literature on the creep properties and behavior of FRC with recommendations for future research. A transparent literature search and filtering methodology were used to identify studies regarding creep on the single fiber level, FRC material level, and level of structural behavior of FRC members. Both experimental and theoretical research are analyzed. The results of the review show that, at the single fiber level, pull-out creep should be considered for steel fiber-reinforced concrete, whereas fiber creep can be a governing design parameter in the case of polymeric fiber reinforced concrete subjected to permanent tensile stresses incompatible with the mechanical time-dependent performance of the fiber. On the material level of FRC, a wide variety of test parameters still hinders the formulation of comprehensive constitutive models that allow proper consideration of the creep in the design of FRC elements. Although significant research remains to be carried out, the experience gained so far confirms that both steel and polymeric fibers can be used as concrete reinforcement provided certain limitations in terms of structural applications are imposed. Finally, by providing recommendations for future research, this study aims to contribute to code development and industry uptake of structural FRC applications.

show abstract

“…Recent studies have also demonstrated that the inclusion of fibers can also significantly improve the serviceability behavior of concrete structures. [18][19][20][21][22][23] However, despite the well-known beneficial properties of steel fiber reinforced concrete (SFRC) in academia, its adoption in practice has typically been taken up in non-load bearing elements for the control of cracking or where the placement of reinforcement is problematic. Codes of practice such as [24][25][26][27][28] indeed contain detailed and accepted methods which are capable in predicting the strength of SFRC elements subjected to shear and flexure.…”

Section: Introductionmentioning

confidence: 99%

A unified approach for determining the strength of Frc members subjected to torsion—Part I: Experimental investigation

Facconi

Amin

Minelli

et al. 2021

Structural Concrete

Self Cite

View full text Add to dashboard Cite

The strength and behavior of fiber reinforced concrete (FRC) members subjected to torsion has received little attention in the literature. The primary objective of including fibers in concrete is to bridge cracks once they form, and in doing so, provide some post‐cracking resistance to the otherwise brittle concrete. This and the accompanying paper that follows present the results of a comprehensive experimental and analytical study aimed at describing the behavior and strength of FRC members subjected to torsion. In this paper, results are presented on large scale pure torsion tests which have been conducted on eighteen 2.7 m long by 0.3 m wide by 0.3 m high beams with varying transverse and longitudinal reinforcement ratios along with varying steel fiber types and dosages. The results of this study demonstrates that the addition of steel fibers significantly increases the stiffness, rigidity and the maximum resisting torque and maximum twist when compared to the same specimen without fibers. The addition of fibers substantially reduced crack widths and crack spacings induced by torsion. The complementary behavior of specimens containing fibers and stirrups is explored along with a critical discussion on members containing low amounts of conventional longitudinal and/or transverse reinforcement.

show abstract

Simplified prediction of the time dependent deflection of SFRC flexural members

Cited by 8 publications

References 19 publications

Simplified time‐dependent crack width prediction for fiber reinforced concrete flexural members

Simplified time‐dependent crack width prediction for fiber reinforced concrete flexural members

Systematic Review on the Creep of Fiber-Reinforced Concrete

A unified approach for determining the strength of Frc members subjected to torsion—Part I: Experimental investigation

Contact Info

Product

Resources

About