A new bond slip model for reinforced concrete structures: Validation by modelling a reinforced concrete tie (original) (raw)
Related papers
A new bond slip model for reinforced concrete structures
Engineering Computations, 2015
Purpose – The purpose of this paper is to present a new bond slip model for reinforced concrete structures. It consists in an interface element (3D) which represents the interface between concrete (modeled in 3D) and steel, modeled using 1D truss elements. Design/methodology/approach – The formulation of the interface element is presented and verified through a comparison with an analytical solution on an academic case. Finally, the model is compared with experimental results on a reinforced concrete tie. Findings – Contrary to the classical perfect or “no-slip” relation which supposes the same displacement between steel and concrete, the proposed model is able to reproduce both global (force-displacement curve) and local (crack openings) results. Originality/value – The proposed approach, applicable to large-scale computations, represents a valuable alternative to the no-slip relation hypothesis to correctly capture the crack properties of reinforced concrete structures.
Experimental and finite element analysis of bond-slip in reinforced concrete
Revista IBRACON de Estruturas e Materiais, 2015
The modeling of reinforced concrete structures has taken advantage of the increasing progress on Computational Mechanics, in such way that complex phenomena, such as cracking and crushing, creep, reinforcement yielding, steel-concrete bond loss, can be modeled in a reasonable realistic way, using the proper set of numerical and computational resources. Among several options, the ones based on the Finite Element Method (FEM) allow complex analysis simulations of reinforced concrete structures, including the interaction of different nonlinear effects. This paper deals with the nonlinear finite element analysis of the bond-slip between reinforcing steel and concrete, taking into account an experimental study previously performed. The FEM analysis presented uses a combination of resources where the material behavior of concrete is described by the Microplane Constitutive Model, and an embedded reinforcement model is used to represent steel inside the concrete and take into account the e...
Development of steel-concrete interface model for structural elements
2018
In numerical applications of reinforced concrete structures, the steel-concrete interface behavior has a vital importance when the cracking properties are investigated. A finite element approach for the steel-concrete interface to be used in large-scale simulations was proposed by (Torre-Casanova, 2013) and (Mang, 2016). It enables to calculate the slip between the steel and concrete in the tangential direction of the interface element representation. The aim is here to improve the initial bond-slip model to be more efficient and more representative. The document is divided into three parts: 1) The existing bond-slip model is evaluated. The bond-slip model is then improved by considering transversal and irreversible bond behaviors under alternative loads. The new bond-slip model is validated with several numerical applications. 2) Confinement effect is implemented in the bond-slip model to capture the effect of external lateral pressure. According to the performed numerical applicat...
Crack opening estimate in reinforced concrete walls using a steel–concrete bond model
Archives of Civil and Mechanical Engineering, 2016
This paper presents the application of a new steel-concrete bond model on a reinforced concrete shear wall, experimentally tested during the French National Project CEOS.FR. The proposed results include both global (evolution of the force as a function of the displacement for example) and local results (crack opening and spacing). A new post-processing method to compute these local properties even in a case of a complex crack pattern (oriented cracks for example) is proposed. It is based on the change in the sign of the bond slip between steel and concrete. The simulated results are in a good agreement with the experiment and validate the developments. Finally, the interest of including a specific steel-concrete bond model in the finite element simulation is highlighted, compared to classical "no-slip" relation.
Local bond stress-slip model for reinforced concrete joints and anchorages with moderate confinement
Canadian Journal of Civil Engineering, 2017
This paper presents a summary of an experimental investigation and the derivation of a bond-slip model for reinforcing steel embedded in moderately confined concrete under monotonic and cyclic loadings. Moderately confined concrete encompasses the domain between unconfined and well-confined concrete, the limits of which are defined in the paper. The proposed constitutive law adapts and extends the well-known Eligehausen-Filippou model for well-confined concrete to moderately confined concrete. It is described by an envelope curve and degradation rules. The former is obtained through a confinement index, defined in this study as a function of the amount of confining steel and concrete, distance between confining steel and the rebar, and concrete segregation effect. It is proposed to adopt the same degradation rules used for well-confined concrete. These rules are validated through statistical tests for moderately confined concrete. They are found to predict correctly the main feature...
Materials and Structures
The bond and slip between concrete and the reinforcement bars, cover a key role in the inter-material force transfer of Reinforced Concrete (RC) structures. In light of the lack of tools able to thoroughly inspect the inner workings of RC structures and to extract reliable bond stress values, modern bond stress–slip (Bond–slip) models are often inaccurate and in contradiction with each other. Considering the recent surge of novel hyper-performant strain sampling tools (Distributed Sensing for example), their application for the creation of novel and physically accurate Bond–slip models is just a matter of time. This being said, one of the main reasons behind the modern coexistence of multiple inaccurate and at times contradictory Bond–slip models is the absence of a tool that has allowed researchers to rapidly corroborate and calibrate their newly created models. To this end, the present article proposes such a Bond–slip validation tool for RC elements. This one is designed to extra...
Analytical Calculation Model for Predicting Cracking Behavior of Reinforced Concrete Ties
Journal of Structural Engineering
This paper formulates an analytical calculation model for predicting the cracking behavior of reinforced concrete ties to provide 6 more consistent crack width calculation methods for large-scale concrete structures in which large bar diameters and covers are used. The 7 calculation model was derived based on the physical behavior of reinforced concrete ties reported from experiments and finite-element 8 analyses in the literature. The derivations led to a second order differential equation for the slip that accounts for the three-dimensional 9 effects of internal cracking by using a proper bond-slip law. The second order differential equation for the slip was solved completely ana-10 lytically, resulting in a closed-form solution in the case of lightly loaded members and in a non-closed-form solution in the case of heavily 11 loaded members. Finally, the paper provides a solution strategy to facilitate a practical and applicable method for predicting the complete 12 cracking response. Comparison with experimental and finite-element results in the literature demonstrated the ability of the calculation model 13 to predict crack widths and crack spacing consistently and on the conservative side regardless of the bar diameter and cover.
SN Applied Sciences, 2019
The bond mechanism plays a decisive role when anchorage failure in a reinforced concrete (RC) member occurs. A refined model of bond-slip is therefore needed to analyse RC members by analytical or finite element (FE) modelling where the anchorage of reinforcement is critical, such as at a lapped-splice or in any situation where the strength of a bar is required to be developed to achieve its ultimate strength. This paper presents results of FE modelling of some experimental RC specimens with anchorage of deformed steel reinforcing bars in tension, including the cases of end development and lapped splices of bars in specimens subjected to bending. The FE modelling of the anchorage length specimens with bond-slip laws calibrated from experimental results was better able to predict the load-deflection behavior observed during experimental tests. A comparison of the results obtained using the calibrated bond-slip laws with those using conventional Fédération Internationale du Béton bond-slip laws is made and discussion is provided on the effects of the anchorage lengths and bar diameters on the bond-slip relationships.
3d Finite Element Modelling of Bond-Slip Between Rebar and Concrete in Pull-Out Test
The Third International Conference On Concrete And Development, 2009
A reinforced concrete material is a composite material made up of two components with unequal mechanical behaviour and physical features. In general, the external load is already applied to concrete and the reinforcing bars receive its part of the load only from the surrounding concrete by bond. In composite structures, the bond between different components of reinforced concrete member has a primordial role and its negligence conducted to poor structural response. Therefore, for modeling of reinforced concrete structures one needs a simple and realistic bond-slip model. There are various finite element models for bond-slip relationship between reinforcement and concrete. In this paper, modeling of the transition region between steel and concrete as a cohesion layer in the finite element program (Ansys) is discussed. A 3D finite element model to represent this layer has been introduced. The layer involves modeling the ribs and effects of slip and bond stress of the bar. The accuracy of the models is assessed by comparison of the finite element numerical response with experimental data from pullout test.