Download or read book Finite Element Modelling of Steel Concrete Bond for Corroded Reinforcement written by Qixin Du and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Reinforcement corrosion is the most common deterioration problem observed in reinforced concrete (RC) structures located at coastal or cold regions. The corrosion process can impact the performance of these structures by inducing damage on the bonding action between concrete and steel, either by the splitting of the concrete cover due to the volumetric expansion of corrosion products or the lubricant effect at the steel/concrete interface as the corrosion by-products accumulate. The current research aims at investigating corrosion-induced deterioration of bond between steel and concrete through finite element (FE) analysis of the flexural behaviour of corroded RC components. By treating the concrete cover as a thick-wall cylinder subjected to internal pressure, the analytical evaluation of impaired bond capacity is studied first and verified against published bonding tests. Then, the formulation of a numerical model is performed using ABAQUS, wherein a link element to simulate the bond behaviour is formulated and implemented through the ABAQUS user-subroutine (UEL) feature according to the validated analytical model. By introducing corrosion-induced damages, i.e., smaller cross-sectional area of reinforcement, splitting of concrete and bond deterioration, in the FE analyses, the results of the numerical model show good agreement with experimental observations. Upon validation of the analytical and FE models, a parametric investigation is conducted, wherein the effects of concrete strength, dimension of reinforcing bars, properties of oxide products, different corrosion damage mechanisms and the corrosion location along the longitudinal reinforcement on the flexural behaviour of RC beams are studied. The results show that the analytical evaluation for bond degradation is impacted by the selection of the post-cracking material model and the thickness of cover that determine the 'holding capacity' after cracking initiation. Also, the density of rust by-products affects the results of the analytical model at high corrosion levels. From the FE model results, it was observed that each damage mechanism due to corrosion contribute to different levels of flexural degradation, although the flexural strength degradation is mainly due to the loss of bonding action. The parametric study also demonstrates that flexural members which have reinforcement corrosion initiated near the supports suffer greater deterioration in flexural capacity than those with damages at mid span. Finally, based on these observations, suggestions for the application of both analytical and numerical models are made.
Download or read book Finite Element Modelling of Corrosion Damaged Reinforced Concrete Structures written by Siavash Habibi and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of steel is the predominant deterioration mechanism of reinforced concrete structures throughout the world. This thesis presents the work performed on VecTor2, a nonlinear finite element analysis program developed at the University of Toronto, for analysis of corrosion damaged reinforced concrete structures. Two well-known types of corrosion, namely uniform and pitting, were considered for modelling. Corrosion damage was incorporated in the algorithms of VecTor2 through reduction of the sectional area of reinforcing steel, the bond strength between the reinforcement and concrete, and the mechanical properties such as yield strength of a corroded reinforcing bar. The employed techniques for incorporating corrosion damage in VecTor2 successfully reproduced the load-deflection response of published experiments. Stochastic simulation of the same experiments, performed by employing the stochastic tools of VecTor2, demonstrated the sensitivity of response quantities to changes in various input parameters forming the basis for further research.
Download or read book A Framework for Stochastic Finite Element Analysis of Reinforced Concrete Beams Affected by Reinforcement Corrosion written by Darek Baingo and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of reinforcing bars is the major cause of deterioration of reinforced concrete (RC) structures in North America, Europe, the Middle East, and many coastal regions around the world. This deterioration leads to a loss of serviceability and functionality and ultimately affects the structural safety. The objective of this research is to formulate and implement a general stochastic finite element analysis (SFEA) framework for the time-dependent reliability analysis of RC beams with corroding flexural reinforcement. The framework is based on the integration of nonlinear finite element and reliability analyses through an iterative response surface methodology (RSM). Corrosion-induced damage is modelled through the combined effects of gradual loss of the cross-sectional area of the steel reinforcement and the reduction bond between steel and concrete for increasing levels of corrosion. Uncertainties in corrosion rate, material properties, and imposed actions are modelled as random variables. Effective implementation of the framework is achieved by the coupling of commercial finite element and reliability software. Application of the software is demonstrated through a case study of a simply-supported RC girder with tension reinforcement subjected to the effects of uniform (general) corrosion, in which two limit states are considered: (i) a deflection serviceability limit state and (ii) flexural strength ultimate limit state. The results of the case study show that general corrosion leads to a very significant decrease in the reliability of the RC beam both in terms of flexural strength and maximum deflections. The loss of strength and serviceability was shown to be predominantly caused by the loss of bond strength, whereas the gradual reduction of the cross-sectional area of tension reinforcement was found to be insignificant. The load-deflection response is also significantly affected by the deterioration of bond strength (flexural strength and stiffness). The probability of failure at the end of service life, due to the effects of uniform corrosion-induced degradation, is observed to be approximately an order of magnitude higher than in the absence of corrosion. Furthermore, the results suggest that flexural resistance of corroded RC beams is controlled by the anchorage (bond) of the bars and not by the yielding of fully bonded tensile reinforcement at failure. This is significant since the end regions can be severely corroded due to chloride, moisture, and oxygen access at connections and expansion joints. The research strongly suggests that bond damage must be considered in the assessment of the time-dependent reliability of RC beams subjected to general corrosion.
Download or read book Additional Finite Element Method for Analysis of Reinforced Concrete Structures at Limit States written by Ermakova A.V. and published by Издательство АСВ. This book was released on 2012 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presents the theoretical basis of Additional Finite Element Method (AFEM), which is a variant of the Finite Element Method (FEM) for analysis of reinforced concrete structures at limit state. AFEM adds to the traditional sequence of problem by FEM the units of the two well-known methods of the structural design: method of additional loads and limit state method. The problem is solved by introduction of ideal failure models and additional design diagrams formed from additional finite elements, where each AFE describes the limit state reached by the main element. The main relations defining the properties of AFEs as well as the examples of the use of Additional Finite Element Method for analysis of reinforced concrete structures at limit state are given in the work too.
Download or read book Finite Element Analysis of Prestressed Concrete Structures Using Post Tensioning Steel written by Yu Huang and published by Cambridge Scholars Publishing. This book was released on 2020-05-28 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book details the theory and applications of finite element (FE) modeling of post-tensioned (PT) concrete structures, and provides the updated MATLAB code (as of 2019). The challenge of modeling PT prestressed concrete structures lies in the treatment of the interface between the concrete and prestressing tendons. Using MATLAB, this study develops an innovative nonlinear FE formulation which incorporates contact techniques and engineering elements to considerably reduce the need of computational power. This FE formulation has the ability to simulate different PT frame systems with fully bonded, fully unbonded or partially bonded tendons, as well as actual sliding behavior and frictional effects in the tendons. It also allows for the accurate simulation of anchor seating loss.
Download or read book Finite Element Analysis of Reinforced Concrete Structures II written by Jeremy Isenberg and published by . This book was released on 1993 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection contains 10 papers discussing finite element analysis of reinforced concrete structures presented at an international workshop held in New York, New York, June 2-5, 1991.
Download or read book Finite Element Modelling of Reinforced Concrete Beams with Corroded Shear Reinforcement written by Sebastien Bernard and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a finite element (FE) modelling approach investigating the effects of corroded shear reinforcement on the capacity and behaviour of shear critical reinforced concrete (RC) beams. Shear reinforcement was modelled using a zlocally smearedy approach, wherein the shear reinforcement is smeared within a series of plane-stress concrete elements at the specific stirrup location. This was done with the objective of incorporating both the reduction in cross-sectional area due to corrosion and the corresponding expansion of corrosion products build up. Corrosion damage was incorporated through equivalent straining induced by the corrosion build up on the affected surrounding concrete where the concrete cover was treated as a thick-wall cylinder subjected to internal pressure. Strains were introduced in the FE model using fictitious smeared horizontal pre-stressing steel, with a compressive pre-straining level related to the degree of corrosion penetration of the reinforcement. The FE modelling approach was first validated against published test data of shear critical RC beams with and without stirrup corrosion. The proposed modelling approach successfully reproduces the load deformation response as well as the failure mode and cracking patterns of the published experimental tests. Upon validation of the FE model, the work was extended to a parametric analysis of important shear design variables, such as the shear span-to-depth ratio, beam width and stirrup spacing The FE analyses were carried out for three increasing levels of corrosion (low, moderate and high) applied to affected stirrups within the critical section of the beams and based on steel mass loss (10%, 30% and 50%, respectively). In general, the results show a reduction in load carrying capacity accompanied by a softening of the load-deformation curves with each increasing level of corrosion. In most of the cases, a reduction in deflection associated to peak loads was also observed for moderate and high levels of corrosion. The impact of the various parameters was studied with respect to strength and deformation, as well as crack angle and mid-height horizontal strain. This was done in an effort to compare FE values to those provided by the CSA A23.3 design equations. The CSA A23.3 shear design equations were compared against FE analysis data in terms of residual shear strength estimation and individual component contributions to shear resistance (i.e., concrete and steel). The comparisons revealed an over conservative estimation for both strength and concrete contributions and an overestimation of the steel contribution. This divergence was attributed to a transition in shear behaviour within the critical section. Based on the progression of the concrete compressive struts with increasing corrosion and predicted crack angle, it was found that stresses in affected sections are redistributed towards adjacent undamaged material. The shear resistance mechanism generally transitioned from typical beam behaviour towards an arching-dominated one. Finally, based on important findings from the literature and the work conducted within this research, important considerations for assessment practice are suggested.
Download or read book Modelling of Corroding Concrete Structures written by Carmen Andrade and published by Springer Science & Business Media. This book was released on 2011-02-04 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: These are the papers presented at the Fib-RILEM workshop held in Madrid, Spain, in November 2010. The assessment of deterioration and aging of concrete structures, most commonly through reinforcement corrosion, is not considered in current structural codes or standards. Some guidelines manuals exist, and research has been done, but there is as yet no accepted methodology nor models that could be used by engineers. This book deals with all aspects related to modelling of corroding structures and provides state-of-the-art information on structural models for corroding structures.
Download or read book Finite Element Design of Concrete Structures written by Guenter Axel Rombach and published by Thomas Telford. This book was released on 2004 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Finite Element Design of Concrete Structures: practical problems and their solutions the author addresses this blind belief in computer results by offering a useful critique that important details are overlooked due to the flood of information from the output of computer calculations. Indeed, errors in the numerical model may lead in extreme cases to structural failures as the collapse of the so-called Sleipner platform has demonstrated.
Download or read book Finite Element Analysis of Reinforced Concrete Structures written by Tadaaki Tanabe and published by Aci International. This book was released on 2001 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Engineering Materials Structures and Systems Innovations Mechanics and Applications written by Alphose Zingoni and published by CRC Press. This book was released on 2019-08-21 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Engineering Materials, Structures and Systems: Innovations, Mechanics and Applications comprises 411 papers that were presented at SEMC 2019, the Seventh International Conference on Structural Engineering, Mechanics and Computation, held in Cape Town, South Africa, from 2 to 4 September 2019. The subject matter reflects the broad scope of SEMC conferences, and covers a wide variety of engineering materials (both traditional and innovative) and many types of structures. The many topics featured in these Proceedings can be classified into six broad categories that deal with: (i) the mechanics of materials and fluids (elasticity, plasticity, flow through porous media, fluid dynamics, fracture, fatigue, damage, delamination, corrosion, bond, creep, shrinkage, etc); (ii) the mechanics of structures and systems (structural dynamics, vibration, seismic response, soil-structure interaction, fluid-structure interaction, response to blast and impact, response to fire, structural stability, buckling, collapse behaviour); (iii) the numerical modelling and experimental testing of materials and structures (numerical methods, simulation techniques, multi-scale modelling, computational modelling, laboratory testing, field testing, experimental measurements); (iv) innovations and special structures (nanostructures, adaptive structures, smart structures, composite structures, bio-inspired structures, shell structures, membranes, space structures, lightweight structures, long-span structures, tall buildings, wind turbines, etc); (v) design in traditional engineering materials (steel, concrete, steel-concrete composite, aluminium, masonry, timber, glass); (vi) the process of structural engineering (conceptualisation, planning, analysis, design, optimization, construction, assembly, manufacture, testing, maintenance, monitoring, assessment, repair, strengthening, retrofitting, decommissioning). The SEMC 2019 Proceedings will be of interest to civil, structural, mechanical, marine and aerospace engineers. Researchers, developers, practitioners and academics in these disciplines will find them useful. Two versions of the papers are available. Short versions, intended to be concise but self-contained summaries of the full papers, are in this printed book. The full versions of the papers are in the e-book.
Download or read book Finite Element Analysis of Bond Characteristics at the FRP concrete Interface written by Mani Balazadeh Minouei and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Reinforced concrete structures are prone to corrosion in harsh environments. Fibre-Reinforced Polymer (FRP) laminates are more resistant than steel elements, such as bars and plate in aggressive environments; they can be used as a barrier to protect concrete structures; however, poor bond between FRP composite laminates and structural concrete can prevent utilizing the full structural and protective capacity of FRP-concrete composite system, therefore, it is important to develop good bond between concrete and the FRP to ensure the integrity and durability of the FRP-concrete system. There is a need to understand the bond characteristics at the FRP laminates-concrete interface, and the various parameters influencing the bond performance of the composite system. This research program consists of numerical modeling of the double lap pull-off tests conducted by Ali et.al (2012) and comparing the computed values with the experimental results for two different batches, along with an evaluation of the various parameters influencing bond between FRP laminates and concrete. The ABAQUS 6.10.1 program was used to model the double lap pull-off test. Shell elements were used to model FRP laminates, solid elements for concrete and steel and cohesive elements for modeling the epoxy joint. The constitutive models for the materials were selected based on their experimental behavior. A linear elastic model was used for modeling FRP laminates and steel, elastoplastic behavior was used for modeling epoxy and damaged plasticity model was used for modeling concrete.Numerical and experimental curves reflected similar responses. In the first batch the average ultimate load in the tests was 70.7 kN , while the ultimate load for the numerical analysis was 73.8 kN, showing a difference of 4.6% . Also, the average experimental value of strain at the center of the FRP laminate was 2657x[(10)]^(-6), while the ultimate strain in numerical simulation was 3023x[(10)]^(-6), showing an acceptable difference of 12.1 %. In the second batch, the average of experimental ultimate load was 54.5kN, while the ultimate load in numerical analysis was 58.6kN, with a difference of only 5.4%. The computed ultimate strain is 2320 x[(10)]^(-6), while the average of ultimate strain in experimental study was 2173x[(10)]^(-6), showing a discrepancy of 6.3%. Also, the effect of different geometrical factors on the bond behavior of FRP and concrete was studied; it was concluded that, the most effective geometrical parameter influencing bond between FRP and concrete was the bonded width of the FRP laminate." --
Download or read book Bond of Reinforcement in Concrete written by fib Fédération internationale du béton and published by fib Fédération internationale du béton. This book was released on 2000-01-01 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In 1993, the CEB Commission 2 Material and Behavior Modelling established the Task Group 2.5 Bond Models. It's terms of reference were ... to write a state-of-art report concerning bond of reinforcement in concrete and later recommend how the knowledge could be applied in practice (Model Code like text proposal)... {This work} covers the first part ... the state-of-art report."--Pref.
Download or read book Practitioners Guide to Finite Element Modelling of Reinforced Concrete Structures written by fib Fédération internationale du béton and published by fib Fédération internationale du béton. This book was released on 2008-01-01 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-linear computer analysis methods have seen remarkable advancement in the last half-century. The state-of-the-art in non-linear finite element analysis of reinforced concrete has progressed to the point where such procedures are close to being practical, every-day tools for design office engineers. Non-linear computer analysis procedures can be used to provide reliable assessments of the strength and integrity of damaged or deteriorated structures, or of structures built to previous codes, standards or practices deemed to be deficient today. They can serve as valuable tools in assessing the expected behaviour from retrofitted structures, or in investigating and rationally selecting amongst various repair alternatives. fib Bulletin 45 provides an overview of current concepts and techniques relating to computer-based finite element modelling of structural concrete. It summarises the basic knowledge required for use of nonlinear analysis methods as applied to practical design, construction and maintenance of concrete structures, and attempts to provide a diverse and balanced portrayal of the current technical knowledge, recognizing that there are often competing and conflicting viewpoints. This report does not give advice on picking one model over another but, rather, provides guidance to designers on how to use existing and future models as tools in design practice, in benchmarking of their models against established and reliable test data and in selecting an appropriate safety factor as well as recognising various pitfalls. fib Bulletin 45 is intended for practicing engineers, and therefore focuses more on practical application and less on the subtleties of constitutive modelling.
Download or read book Computational Modelling of Concrete Structures written by Nenad Bicanic and published by CRC Press. This book was released on 2014-03-04 with total page 1120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The EURO-C conference series (Split 1984, Zell am See 1990, Innsbruck 1994, Badgastein 1998, St Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St Anton am Alberg 2014) brings together researchers and practising engineers concerned with theoretical, algorithmic and validation aspects associated with computational simulations of concrete and
Download or read book Rehabilitation of Concrete Structures with Fiber Reinforced Polymer written by Riadh Al-Mahaidi and published by Butterworth-Heinemann. This book was released on 2018-11-12 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rehabilitation of Concrete Structures with Fiber Reinforced Polymer is a complete guide to the use of FRP in flexural, shear and axial strengthening of concrete structures. Through worked design examples, the authors guide readers through the details of usage, including anchorage systems, different materials and methods of repairing concrete structures using these techniques. Topics include the usage of FRP in concrete structure repair, concrete structural deterioration and rehabilitation, methods of structural rehabilitation and strengthening, a review of the design basis for FRP systems, including strengthening limits, fire endurance, and environmental considerations. In addition, readers will find sections on the strengthening of members under flexural stress, including failure modes, design procedures, examples and anchorage detailing, and sections on shear and torsion stress, axial strengthening, the installation of FRP systems, and strengthening against extreme loads, such as earthquakes and fire, amongst other important topics. Presents worked design examples covering flexural, shear, and axial strengthening Includes complete coverage of FRP in Concrete Repair Explores the most recent guidelines (ACI440.2, 2017; AS5100.8, 2017 and Concrete society technical report no. 55, 2012)
Download or read book Computational Modelling of Concrete Structures written by Günther Meschke and published by CRC Press. This book was released on 2018-01-31 with total page 1034 pages. Available in PDF, EPUB and Kindle. Book excerpt: The EURO-C conference series (Split 1984, Zell am See 1990, Innsbruck 1994, Badgastein 1998, St. Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St. Anton am Arlberg 2014, and Bad Hofgastein 2018) brings together researchers and practising engineers concerned with theoretical, algorithmic and validation aspects associated with computational simulations of concrete and concrete structures. Computational Modelling of Concrete Structures reviews and discusses research advancements and the applicability and robustness of methods and models for reliable analysis of complex concrete, reinforced concrete and pre-stressed concrete structures in engineering practice. The contributions cover both computational mechanics and computational modelling aspects of the analysis and design of concrete and concrete structures: Multi-scale cement and concrete research: experiments and modelling Aging concrete: from very early ages to decades-long durability Advances in material modelling of plain concrete Analysis of reinforced concrete structures Steel-concrete interaction, fibre-reinforced concrete, and masonry Dynamic behaviour: from seismic retrofit to impact simulation Computational Modelling of Concrete Structures is of special interest to academics and researchers in computational concrete mechanics, as well as industry experts in complex nonlinear simulations of concrete structures.