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1 – 10 of 26
Article
Publication date: 6 December 2018

Jinliang Liu, Yanmin Jia, Guanhua Zhang and Jiawei Wang

The calculation of the crack width is necessary for the design of prestressed concrete (PC) members. The purpose of this paper is to develop a numerical model based on the…

Abstract

Purpose

The calculation of the crack width is necessary for the design of prestressed concrete (PC) members. The purpose of this paper is to develop a numerical model based on the bond-slip theory to calculate the crack width in PC beams.

Design/methodology/approach

Stress calculation method for common reinforcement after beam crack has occurred depends on the difference in the bonding performance between prestressed reinforcement and common reinforcement. A numerical calculation model for determining the crack width in PC beams is developed based on the bond-slip theory, and verified using experimental data. The calculation values obtained by the proposed numerical model and code formulas are compared, and the applicability of the numerical model is evaluated.

Findings

The theoretical analysis and experimental results verified that the crack width of PC members calculated based on the bond-slip theory in this study is reasonable. Furthermore, the stress calculation method for the common reinforcement is verified. Compared with the model calculation results obtained in this study, the results obtained from code formulas are more conservative.

Originality/value

The numerical calculation model for crack width proposed in this study can be used by engineers as a reference for calculating the crack width in PC beams to ensure the durability of the PC member.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 19 March 2020

Behrooz Yousefi, Mohammad Reza Esfahani and Mohammadreza Tavakkolizadeh

This paper aims to develop a new multi-fiber element for predicting the structural behavior of planar-reinforced concrete (RC) members.

Abstract

Purpose

This paper aims to develop a new multi-fiber element for predicting the structural behavior of planar-reinforced concrete (RC) members.

Design/methodology/approach

In this work, an exact multi-directional stiffness matrix is analytically derived based on the post-cracking bond-slip interaction between concrete and steel bars. The approach is also extended for large displacement analysis using Green–Lagrange finite strain tensor. In the proposed formulation, the weak form of governed differential equations is approximated by a trial-function expansion based on a finite strain-description and an additional degree of freedom for steel bars.

Findings

The findings provide a realistic description of cracking in the concrete structure. Numerical studies are conducted to examine the accuracy of the suggested approach and its capability to predict fairly complex responses of RC models. The findings prove that the proposed element can evaluate local and global responses of RC members, and it can be used as a reliable tool to reflect bond-slip effects in large displacement level. This leads to a robust and precise model for non-linear analysis of RC structures.

Originality/value

The methodology is capable of simulating coupled inelastic shear-flexural behavior of RC members through local stress field theory and Timoshenko beam model.

Article
Publication date: 23 January 2020

Haitao Wang, Tao Guo and Haoyu Sun

This paper aims to focus on establishing the bond-slip constitutive relation of mortar anchor under high loading rates by the dynamic pull-out test.

Abstract

Purpose

This paper aims to focus on establishing the bond-slip constitutive relation of mortar anchor under high loading rates by the dynamic pull-out test.

Design/methodology/approach

Self-made specimens were made for the dynamic pull-out test to explore the bond performance of mortar anchor, and the bond-slip constitutive relation of mortar anchor under high loading rates was established according to the analysis of test data.

Findings

During the loading process, the position of the peak bond stress was observed to translate to the free end. The bearing capacity of the mortar anchor was enhanced to some extent due to the increase of the loading rate.

Originality/value

The bond-slip constitutive relation of mortar anchor under high loading rates was established with the introduction of the position function and dynamic-load expanded coefficient.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 4
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 24 February 2012

Smitha Gopinath, Nagesh Iyer, J. Rajasankar and Sandra D'Souza

The purpose of this paper is to present integrated methodologies based on multilevel modelling concepts for finite element analysis (FEA) of reinforced concrete (RC) shell…

Abstract

Purpose

The purpose of this paper is to present integrated methodologies based on multilevel modelling concepts for finite element analysis (FEA) of reinforced concrete (RC) shell structures, with specific reference to account for the nonlinear behaviour of cracked concrete and the other associated features.

Design/methodology/approach

Geometric representation of the shell is enabled through multiple concrete layers. Composite characteristic of concrete is accounted by assigning different material properties to the layers. Steel reinforcement is smeared into selected concrete layers according to its position in the RC shell. The integrated model concurrently accounts for nonlinear effects due to tensile cracking, bond slip and nonlinear stress‐strain relation of concrete in compression. Smeared crack model having crack rotation capability is used to include the influence of tensile cracking of concrete. Propagation and change in direction of crack along thickness of shell with increase in load and deformation are traced using the layered geometry model. Relative movement between reinforcing steel and adjacent concrete is modelled using a compatible bond‐slip model validated earlier by the authors. Nonlinear iterative solution technique with imposed displacement in incremental form is adopted so that structures with local instabilities or strain softening can also be analysed.

Findings

Proposed methodologies are validated by evaluating ultimate strength of two RC shell structures. Nonlinear response of McNeice slab is found to compare well with that of experiment available in literature. Then, a RC cooling tower is analysed for factored wind loads to study its behaviour near ultimate load. Numerical validation demonstrates efficacy and usefullness of the proposed methodologies for nonlinear FEA of RC shell structures.

Originality/value

The present paper integrates critical methodologies used for behaviour modelling of concrete and reinforcement with the physical interaction among them. The study is unique by considering interaction of tensile cracking and bond‐slip which are the main contributors to nonlinearity in the nonlinear response of RC shell structures. Further, industrial application of the proposed modelling strategy is demonstrated by analysing a RC cooling tower shell for its nonlinear response. It is observed that the proposed methodologies in the integrated manner are unique and provide stability in nonlinear analysis of RC shell structures.

Article
Publication date: 21 March 2022

Jason Martinez and Ann Jeffers

A methodology for producing an elevated-temperature tension stiffening model is presented.

Abstract

Purpose

A methodology for producing an elevated-temperature tension stiffening model is presented.

Design/methodology/approach

The energy-based stress–strain model of plain concrete developed by Bažant and Oh (1983) was extended to the elevated-temperature domain by developing an analytical formulation for the temperature-dependence of the fracture energy Gf. Then, an elevated-temperature tension stiffening model was developed based on the modification of the proposed elevated-temperature tension softening model.

Findings

The proposed tension stiffening model can be used to predict the response of composite floor slabs exposed to fire with great accuracy, provided that the global parameters TS and Kres are adequately calibrated against global structural response data.

Originality/value

In a finite element analysis of reinforced concrete, a tension stiffening model is required as input for concrete to account for actions such as bond slip and tension stiffening. However, an elevated-temperature tension stiffening model does not exist in the research literature. An approach for developing an elevated-temperature tension stiffening model is presented.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 7 March 2008

Boris Trogrlic and Ante Mihanovic

This paper aims to present a new numerical model for the stability and load‐bearing capacity computation of space reinforced‐concrete (R/C) frame structures. Both material…

Abstract

Purpose

This paper aims to present a new numerical model for the stability and load‐bearing capacity computation of space reinforced‐concrete (R/C) frame structures. Both material and geometric nonlinearities are taken into account. The R/C cross‐sections are assumed to undergo limited distortion under torsional action.

Design/methodology/approach

A simple, global discretization using beam‐column finite elements is preferred to a full, global discretization using 3D elements. This is more acceptable from a practical point of view. The composite cross‐section is discretized using 2D elements to apply the fiber decomposition procedure to solve the material and geometrical nonlinear behavior of the cross‐section under biaxial moments and axial forces. A local discretization of each beam element based on the comparative body model (i.e. a prismatic body discretized using brick elements, element by element, during the incremental‐iterative procedure) allows determining the torsional constant of the cross‐section under limited warping. The classical global iterative‐incremental procedure is then used to solve the resulting material and geometric nonlinear problem.

Findings

It has been noticed that, in case of a limited distortion of the cross‐section, the torsional constant of homogeneous (linear elastic) materials is greater than the one obtained from the Saint‐Venant theory. However, due to low‐tensile strength of concrete materials, the torsional constant decreases significantly after an early loading phase, primarily due to the lack of reinforcing flanges.

Research limitations/implications

The current study does not cover the torsion analysis of R/C cross‐section with stirrups. Besides, the bond‐slip effect between concrete and steel reinforcement is not taken into account, nor is the local buckling of the beam flanges and rebar.

Practical implications

This new numerical model has been implemented in a computer program for effectively computing the nonlinear stability and load bearing capacity of space R/C frames.

Originality/value

The authors believe that the comparative body model should bring a new approach to the solution of torsion problems with limited distortion of cross‐sections in material and geometric nonlinear analysis of space R/C frames.

Details

Engineering Computations, vol. 25 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 14 November 2008

Virgínia Maria Rosito d'Avila, Daiane de Sena Brisotto and Eduardo Bittencourt

The purpose of this paper is to describe the development of an embedded crack finite element (FE) model for reinforced concrete (RC) structures, including a bond‐slip

Abstract

Purpose

The purpose of this paper is to describe the development of an embedded crack finite element (FE) model for reinforced concrete (RC) structures, including a bond‐slip methodology to take into consideration the steel contribution in the rupture process, capable of capturing the global behavior of the structure as well as details of cracking phenomenon.

Design/methodology/approach

The reinforcement contribution is added in the equilibrium at element level in an embedded crack FE model, based on displacement localization lines inside the elements.

Findings

The model is able to determine the steel stress in the crack besides the volumetric average steel stress. It is shown that the steel stress in the crack can be considerable greater than the average value. Other important aspect detected is the contribution of the concrete softening in the steel stress in the crack and in the overall behavior. The number, the distribution and the opening of cracks can be estimated too.

Practical implications

The yield of the steel in the cracking process can be detected more precisely by this methodology, allowing a better design and understanding of RC structures. In addition, the knowledge of crack openings is an important information to predict corrosion and other degradation phenomena of the reinforcement bars.

Originality/value

The bond‐slip procedure is linked with the embedded crack model in an original way: sliding gives the crack width. Moreover, the inclusion of steel forces in the crack equilibrium balance was not a usual procedure and permits an understanding of reinforcement effect in both levels (macro and micro) studied in this work.

Details

Engineering Computations, vol. 25 no. 8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 1986

Michael D. Kotsovos and Milija N. Pavlović

A non‐linear finite element program for concrete structures is outlined, with emphasis on the material modelling. It is shown that the package can be used with confidence…

Abstract

A non‐linear finite element program for concrete structures is outlined, with emphasis on the material modelling. It is shown that the package can be used with confidence in the analysis of practical structural forms. In addition, there is considerable potential for the application of the program to research and design.

Details

Engineering Computations, vol. 3 no. 3
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 1 January 1992

ZHI‐HUA ZHONG and JAROSLAV MACKERLE

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years…

Abstract

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

Details

Engineering Computations, vol. 9 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 2 January 2009

Adnan Ibrahimbegovic, Guillaume Hervé and Pierre Villon

The purpose of this paper is to provide the methodology for structural design of complex massive structures under impact by a large airplane.

Abstract

Purpose

The purpose of this paper is to provide the methodology for structural design of complex massive structures under impact by a large airplane.

Design/methodology/approach

Using case studies, the issues related to multi‐scale modelling of inelastic damage mechanisms for massive structures are discussed, as well as the issues pertaining to the time integration schemes in presence of different scales in time variation of different sub‐problems, brought by a particular nature of loading with a very short duration) and finally the issues related to model reduction seeking to provide an efficient and yet sufficiently reliable basis for parametric studies which are an indispensable part of a design procedure.

Findings

Several numerical simulations are presented in order to further illustrate the approaches proposed herein. Concluding remarks are stated regarding the current and future research in this domain.

Originality/value

Proposed design procedure for complex massive engineering structures under impact by a large airplane provides on one side a very reliable representation of inelastic damage mechanisms and external loading represented by the solution of the corresponding contact/impact problem, and on the other side a very efficient basis obtained by model reduction for performing the parametric design studies.

Details

Engineering Computations, vol. 26 no. 1/2
Type: Research Article
ISSN: 0264-4401

Keywords

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