Download or read book Prediction of Steel Force Distribution in Reinforced Concrete Members from Bond slip Characteristics written by Joseph P. Colaco and published by . This book was released on 1965 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Highway Research in Progress written by and published by . This book was released on 1973 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book The Summary of Engineering Research written by University of Illinois (Urbana-Champaign campus). Office of Engineering Publications and published by . This book was released on 1965 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1970 with total page 1090 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Geodex Structural Information Service written by Geodex International and published by . This book was released on 1984 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts written by and published by . This book was released on 1965 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstracts of dissertations and monographs in microform.

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.

Download or read book Post Crack and Post Peak Behavior of Reinforced Concrete Members by Nonlinear Finite Element Analysis written by Yi Wu and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Post-crack and Post-peak Behavior of Reinforced Concrete Members by Nonlinear Finite Element Analysis" by Yi, Wu, 吳奕, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled POST-CRACK AND POST-PEAK BEHAVIOR OF REINFORCED CONCRETE MEMBERS BY NONLINEAR FINITE ELEMENT ANALYSIS Submitted by Wu Yi for the degree of Doctor of Philosophy at the University of Hong Kong in September 2006 This thesis investigates the post-crack and post-peak behavior of reinforced concrete members by using finite element analysis. To achieve this, a finite element code with displacement controlled iterative scheme is developed. The finite element code is able to represent the complete load-deflection curve of reinforced concrete member from the initial loading stage till the post-peak stage. Bond-slip interaction between concrete and longitudinal reinforcement is included. To validate the finite element code, experiments of reinforced concrete members with different longitudinal reinforcement, web reinforcement, concrete strength and axial compression are studied. Case studies show that if the bond-slip is neglected in the finite element analysis, the predicted load-deflection curve and crack pattern will give less accuracy. A study of the mesh size-effect of concrete element shows that the mesh should be fine enough in order to give better prediction. By including the bond element and using proper element size, the results show that the proposed finite element code gives a good description of the behavior of reinforced concrete members, including crack patterns and the load-deflection responses. i By using this finite element code, reinforced concrete beams with different concrete grade, steel ratio are studied to investigate the post-crack behavior of reinforced concrete members. The analysis demonstrates that the predicted load will be under-estimated after the concrete has cracked if the tension-stiffening effect is neglected in the section analysis. Based on the results obtained from the finite element analysis, three new concrete stress distribution blocks are proposed. Compared with the current design codes in which the contribution of cracked concrete in tension is simply neglected or other far more complicated methods proposed for the finite element analysis, the tension-stiffening effect can be taken into account in a simple manner in the proposed models for the section analysis of reinforced concrete beams. Several classic reinforced beams are adopted to validate the proposed models. The results show that the proposed models give a good description of the load-deflection behavior of the reinforced concrete members for cracked concrete. In the investigation of the post-peak behavior of reinforced concrete beams, it is found that beyond the ultimate strength, the strain reversal history of longitudinal reinforcement has significant effects on the load-deflection behavior of the member. The predicted load may be over-estimated for an under-reinforced concrete beam when the strain reversal history of longitudinal reinforcement is neglected. It is therefore suggested that the strain history effect should be included for more accurate prediction of the post-peak load-deflection curves of reinforced concrete members. The variation of curvature along the beam length is also investigated. It is shown that the phenomenon of curvature reversal occurs at the post-peak stage for over- reinforced concrete sections in a simply supported beam that is subjected to concen

Download or read book Bond Characteristics of Micro Composite Multi Structural Formable Steel Used in Reinforced Concrete Structures written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The bond performance of a unique type of reinforcing steel rebars, claimed to have high corrosion resistance as well as high tensile strength, with concrete was studied. The objective was to investigate the bond behavior of straight rebars made out of this steel, named MMFX, embedded in concrete flexural members and to examine the applicability of the current expressions for bond force to predict the bond capacity of the MMFX bars embedded in concrete. Two phases of experimental investigation was conducted. In the first phase, four beam end specimens were tested and in the second phase eight splice beams were studied. The bond behavior of the MMFX steel bars was found to be similar to that of carbon steel. The bond strength of the MMFX is significantly reduced as the tensile stresses developed in the bar went beyond the proportional limit. Both the ACI code 318-02 equation for bond force and the current equation proposed by the ACI committee 408 for bond force gave conservative prediction for bond force for low stress levels. However, at high stress levels, the prediction of the two equations went to the unconservative side. The non linear behavior of the MMFX stress-strain curve was the reason behind the unconservative prediction. The above two equations were modified to ensure conservative prediction at high stress levels. A second degree best fitting curve was found to be the best to describe the relationship between the splice length and the bond force capacity for both # 6 and # 8 MMFX bars.

Download or read book International Symposium on the Effects of Repeated Loading of Materials and Structures written by and published by . This book was released on 1966 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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:

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1974 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Composite Materials in Concrete Construction written by Ravindra K Dhir and published by Thomas Telford. This book was released on 2002-08-28 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete is a global material that underwrites commercial wellbeing and social development. The pressure for change and improvement of performance is relentless and necessary. Concrete must keep evolving to satisfy the increasing demands of all its users.

Download or read book CEB FIP model code 1990 final draft chapters1 3 written by FIB – International Federation for Structural Concrete and published by FIB - International Federation for Structural Concrete. This book was released on 1991-07-01 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bond slip characteristics of new type concrete reinforcing steel written by Chu-Chin Lee and published by . This book was released on 1950 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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).