EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Further Studies of the Bond Strength and Slip Characteristics of Galvanized and Epoxy Coated Steel Reinforcement in Concrete

Download or read book Further Studies of the Bond Strength and Slip Characteristics of Galvanized and Epoxy Coated Steel Reinforcement in Concrete written by Stephen Ross Yeomans and published by . This book was released on 1993 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Characteristics of Reinforced Concrete Bond at High Strain Rates

Download or read book Characteristics of Reinforced Concrete Bond at High Strain Rates written by Eric Jacques and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the on-going intensity of research in the field of protective structural design, one topic that has been largely ignored in the literature is the effect of high strain rates on the bond between reinforcing steel and the surrounding concrete. Therefore, a comprehensive research program was undertaken to establish the effect of high strain rates on reinforced concrete bond. The experimental research consisted of the construction and testing of fourteen flexural beam-end bond specimens and twenty-five lap-spliced reinforced concrete beams. The physical and material properties of the specimens were selected based on a range of design parameters known to significantly influence bond strength. In order to establish a baseline for comparison, approximately half of the total number of specimens were subjected to static testing, while the remainder were subjected to dynamic loading generated using a shock tube. The strain rates generated using the shock tube were consistent with those obtained for mid- and far-field explosive detonation. Results of the beam-end and lap splice beam tests showed that the flexural behaviour of reinforced concrete was significantly stronger and stiffer when subjected to dynamic loading. Furthermore, the high strain rate bond strength was always greater than the corresponding low strain rate values, yielding an average dynamic increase factor (DIF) applied to ultimate bond strength of 1.28. Analysis of the low and high strain rate test results led to the development of empirical expressions describing the observed strain rate sensitivity of reinforced concrete bond for spliced and developed bars with and without transverse reinforcement. The predictive accuracy of the proposed DIF expressions was assessed against the experimental results and data from the literature. It was found that the dynamic bond strength of reinforced concrete can be predicted with reasonably good accuracy and that the proposed DIF expressions can be used for analysis and design of protective structures. An analytical method was also developed to predict the flexural load-deformation behaviour of reinforced concrete members containing tension lap splices. The analysis incorporated the effect of reinforcement slip through the use of pseudo-material stress-strain relationships, in addition to giving consideration to the effect of high strain rates on bond-slip characteristics and on the material properties of concrete and steel. A comparison of the analytical predictions with experimental data demonstrated that the proposed analysis technique can reasonably predict the flexural response of beams with tension lap splices. The results also demonstrated that the model is equally applicable for use at low- and high-strain rates, such as those generated during blast and impact.

Book Effect of Deformation Porperties on Bond slip Characteristics of Reinforcing Bars

Download or read book Effect of Deformation Porperties on Bond slip Characteristics of Reinforcing Bars written by Ghassan Khaled Jumah and published by . This book was released on 1992 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theory of reinforced concrete is based on stress transfer between steel and concrete. In order for the steel to develop its full yield force in tension, there should be some bond between that steel and the surrounding concrete. With the deformed bars, used in reinforced concrete construction since many decades, the problem of bond was the topic for many research programs dedicated for the investigation of the factors influencing that bond, Some of these factors are : bar size, cover thickness, spacing between embedded bars, and deformation properties of the bar itself. The objective of our research work was to investigate the effect of rib geometry or rib deformation properties on the bond-slip characteristics of deformed reinforcing bars. For that purpose, plain round Grade 60 bars 20.6 mm (0.811 in.) in diameter were machined to simulate #6 bars. Fifty six of these test bars were tested in eccentric pullout tests. The specimen was a concrete block with a 10-in. length and a 12in.xl2in. cross section. The bar was embedded along the 10-in. length and was loaded in tension until failure of the specimen in a V-notch splitting mode, where the test was halted. Such a short embedment length (10 in.^ for the test bar was chosen in order to avoid yielding of the bar and to minimize the difference in tensile stresses between the loaded-end and the free-end of the bar. The load and the free-end slip of the bar was monitored during the test. Seven series of pullout specimens were prepared and tested, and replicates were included to check the reliability of the test setup and the obtained results. In series ONE and FOUR, the main variable was the rib face angle where five rib face angles were investigated, 30, 45, 60, 75, and 90 degrees. The concrete compressive strength in series ONE was 3000 psi while in series SIX, it was 6000 psi. The main variable in series TWO and FIVE was the rib spacing. Five values of rib spacings were investigated, 0.3 in. (0.37 db), 0.35 in. (0.43 dO, 0.4 in. (0.49 db), 0.45 in. (0.55 db), and 0.5 in. (0.62 db). The rib height was investigated in series THREE and SIX with two different concrete compressive strengths, 3000 and 6000 psi respectively. Four values of rib heights were investigated; 0.04 in. (0.05 db), 0.06 in. (0.074 db), 0.08 in. (0.1 db), and 0.1 in. (0.124 db). Based on the test results of the first six series, the values for the variables in the seventh series were decided upon. In this last series, the rib spacing was kept constant and equal to 0.4 in. (0.49 db), and four combinations of rib face angles and rib heights were tested. The first two combinations had a rib face of 45 degrees and two different rib heights, 0.06 in. (0.074 db) and 0.08 in. (0.1 db), while the other two had a rib face angle 60 degrees with two different rib heights, 0.06 in. (0.074db) and 0.08 in. (0.1 db).

Book Bond of Reinforcemen Under Controlled Confinement

Download or read book Bond of Reinforcemen Under Controlled Confinement written by and published by . This book was released on 1991 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Twelve specimens were tested to determine the local bond stress-slip characteristics of a No. 6 rebar embedded in a 3-inch diameter concrete cylinder. Radial confining stress around the concrete specimen and radial deformation were assumed to be fundamental variables, together with bond stress and slip, needed to properly describe the interface behavior. Configuration independent bond stress-slip, relationships for a short five-lug embedded length were obtained for various degrees of confining pressure. Maximum bond stresses could be increased almost threefold by increasing the confining stress from 500 to 4500 psi at the bar level. Two types of No. 6 bars with different deformations were investigated. In many reinforced concrete structures, the mode of failure is tensile cracking of the concrete. Where it is important to predict failure or severe damage, proper representation of bond is crucial. Principal gain from inclusion of actual bond-slip properties in the interface between steel rebar and concrete is a realistic prediction of cracking. The spacing, width, and extent of cracks in reinforced concrete are dependent on the assumed bond-slip characteristics. Critical Navy reinforced concrete structures, such as missile test cells and graving drydocks, are designed to withstand large deformations under severe blast and strong-motion earthquake loads. The development of design criteria for these structures requires evaluation of their response where severe deterioration of steel concrete interfaces takes place.

Book Local Bond Stress slip Relationship of Reinforcing Bars Embedded in Fiber Reinforced Concrete Under Splitting Type Failure

Download or read book Local Bond Stress slip Relationship of Reinforcing Bars Embedded in Fiber Reinforced Concrete Under Splitting Type Failure written by Walid Jalkh and published by . This book was released on 1993 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study summarizes experimental results of the local bond stress-slip response of reinforcing bars embedded in fiber reinforced concrete (FRC) under splitting type failure. Pullout specimens were tested to study the effect of several parameters, namely, type, volume fraction, and aspect ratio of fibers, concrete cover to reinforcing bars (or splitting area surrounding the reinforcing bar), and size of reinforcing bar. The experimental results showed that the major contribution of fibers is in the post-splitting range. As compared to plain concrete, the bond behavior of fiber reinforced concrete is more ductile inasmuch as the post-splitting bond stresses are increased. This increase is function of the fiber reinforcing index and of the fiber bond characteristics. The results from the current study were combined with other results reported in technical literature and used to develop a model to describe the bond stress-slip relationship of reinforcing bars embedded in plain and FRC under splitting type failure. The model accounts for all of the important parameters that tend to influence the bond characteristics of reinforcing bar3 as observed in the experiment. It should be mentioned that this study consists the second pact of a two-phase experimental program dealing with the local bond stress-slip characteristics of reinforcing bars embedded in fiber reinforced concrete. While this current phase concentrates on the splitting type of failure, the first part of the study (Ref. 4) emphasized pullout failure.

Book Bond of Reinforcement in Concrete

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.

Book Bond in Concrete

Download or read book Bond in Concrete written by Peter Bartos and published by . This book was released on 1982 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book fib Model Code for Concrete Structures 2010

Download or read book fib Model Code for Concrete Structures 2010 written by fib - federation internationale du beton and published by John Wiley & Sons. This book was released on 2013-12-04 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Federation for Structural Concrete (fib) is a pre-normative organization. 'Pre-normative' implies pioneering work in codification. This work has now been realized with the fib Model Code 2010. The objectives of the fib Model Code 2010 are to serve as a basis for future codes for concrete structures, and present new developments with regard to concrete structures, structural materials and new ideas in order to achieve optimum behaviour. The fib Model Code 2010 is now the most comprehensive code on concrete structures, including their complete life cycle: conceptual design, dimensioning, construction, conservation and dismantlement. It is expected to become an important document for both national and international code committees, practitioners and researchers. The fib Model Code 2010 was produced during the last ten years through an exceptional effort by Joost Walraven (Convener; Delft University of Technology, The Netherlands), Agnieszka Bigaj-van Vliet (Technical Secretary; TNO Built Environment and Geosciences, The Netherlands) as well as experts out of 44 countries from five continents.

Book Bond and anchorage of embedded reinforcement  Background to the fib Model Code for Concrete Structures 2010

Download or read book Bond and anchorage of embedded reinforcement Background to the fib Model Code for Concrete Structures 2010 written by fib - Fédération internationale du béton and published by fib - Fédération internationale du béton. This book was released on 2014-05-01 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of the preparation for the fib Model Code for Concrete Structures 2010, task group 4.5 Bond Models undertook a major review of rules for bond and anchorage of reinforcement in the CEB-FIP Model Code 1990. This bulletin presents the outcome of that review, describes the rationale for the revisions and presents the evidence on which the revisions are based. The principle changes in MC2010 include raising the limit on concrete strength that may be used when determining bond resistance to 110MPa, introduction of a coefficient η4 to cater for different reinforcement Classes, and coverage of new construction materials including epoxy coated and headed bars. The format of design rules has been changed to permit more rational treatment of confinement from concrete cover and transverse reinforcement, the contribution of end hooks and bends for tension bars, and end bearing to compression laps. New guidance is provided covering a range of construction techniques and service environments and the influence of long term degradation. Analyses of various aspects of detailing on performance of laps and anchorages have resulted in discontinuation of the ‘proportion lapped’ factor α6, alterations to requirements of transverse reinforcement at laps, and have resolved inconsistencies in provisions for bundled bars between major national codes. Apparent inconsistencies in existing rules for lapped joints and anchorages and between the local bond/slip model and design rules are also resolved, thus allowing integration of application rules and modelling. Finally, the basis for an attempt to introduce simple detailing rules for laps and anchorages is described.

Book Bond Characteristics of High Strength Concrete

Download or read book Bond Characteristics of High Strength Concrete written by Mehdi Alavi-Fard and published by . This book was released on 1999 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book fib Model Code for Concrete Structures 2010

Download or read book fib Model Code for Concrete Structures 2010 written by fib - f¿d¿ration internationale du b¿ton and published by John Wiley & Sons. This book was released on 2013-10-01 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Federation for Structural Concrete (fib) is a pre-normative organization. 'Pre-normative' implies pioneering work in codification. This work has now been realized with the fib Model Code 2010. The objectives of the fib Model Code 2010 are to serve as a basis for future codes for concrete structures, and present new developments with regard to concrete structures, structural materials and new ideas in order to achieve optimum behaviour. The fib Model Code 2010 is now the most comprehensive code on concrete structures, including their complete life cycle: conceptual design, dimensioning, construction, conservation and dismantlement. It is expected to become an important document for both national and international code committees, practitioners and researchers. The fib Model Code 2010 was produced during the last ten years through an exceptional effort by Joost Walraven (Convener; Delft University of Technology, The Netherlands), Agnieszka Bigaj-van Vliet (Technical Secretary; TNO Built Environment and Geosciences, The Netherlands) as well as experts out of 44 countries from five continents.

Book Interfacial Transition Zone in Concrete

Download or read book Interfacial Transition Zone in Concrete written by J.C. Maso and published by CRC Press. This book was released on 2004-03-01 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important new state-of-the-art report prepared by RILEM Technical Committee 108 ICC. It has been written by a team of leading international experts from the UK, USA, Canada, Israel, Germany, Denmark, South Africa, Italy and France. Research studies over recent years in the field of cement science have focused on the behaviour of the interfaces between the components of cement-based materials. The techniques used in other areas of materials science are being applied to the complex materials found in cements and concretes, and this book provides a significant survey of the present state of the art.

Book Tests of Bond Resistance Between Concrete and Steel

Download or read book Tests of Bond Resistance Between Concrete and Steel written by Willis Appleford Slater and published by . This book was released on 1920 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Bond Stress slip Characteristics of FRP Rebars

Download or read book Bond Stress slip Characteristics of FRP Rebars written by L. Javier Malvar and published by . This book was released on 1994 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: