Download or read book Flexural Behavior of Steel Fiber Reinforced Prestressed Concrete Beams and Double Punch Test for Fiber Reinforced Concrete written by Netra Bahadur Karki and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Steel fibers have widely been used in the past to reinforce brittle materials in many nonstructural applications such as pavement, tunneling lining, etc. On the basis of numerous previous studies, ACI 318-11 [2011] has recently accepted steel fiber as a minimum shear reinforcement replacement with minimum 0.75% volume fraction for both reinforced concrete and prestressed concrete members. However, not much previous research has talked about the flexural behavior of fiber reinforced concrete (FRC). As per ACI 318-11 for tension-controlled sections, the net tensile strains in the outermost layer of steel, et, should be greater than or equal to 0.005 and for the moment redistribution in continuous beam the section should sufficiently ductile (et [greater or equal to] 0.0075). For this, the sections should have small longitudinal reinforcement ratio which ultimately leads to an inefficient beam section with a large cross-sectional area. In contrast, the use of smaller concrete cross sections can lead to a diminished ductile flexural behavior as well as premature shear failure. In this context, the use of steel fiber reinforced concrete could be a potential solution since fiber can increase both the concrete shear strength and it's usable compressive strains. However limited previous researches on the flexural behavior on SFRC beams are available and most of them are of small scales and concentrated only basically for shear behavior. To the best of our knowledge, the large-scale prestressed fiber reinforced concrete beam specimens have yet to be studied for flexure behavior. In this project, six large scale prestressed concrete beams with or without steel fiber along with some material test were tested. Our experimental investigations indicated that even with inclusion of small percentage volume of fraction of steel fiber (Vf =0.75%) could not only increase the ductility and shear strength of the SFRPC beam but also change the failure pattern by increasing usable strain in concrete and steel. A modification on the limit for c/dt ratio and [phi] factor for design of flexural member given in current ACI could be proposed which could imply the smaller sections with higher longitudinal reinforcement ratio and less shear reinforcement. could be used. Any standard material test results have to ensure that FRC has, at least, been batched properly and it can give indications of probable performance when used in structures. In the current material testing method suggested by ACI, the third point bending test (ASTM C1609) has an inherent problem in that the coefficients of variations for post cracking strength and residual strength are generally very high on the order of 20%. The direct tensile test can be a more appropriate material. However, it is currently not recommended as standard method in the U.S. Because of it's difficultly in gripping arrangement which will lead to cracking of the specimen at the grips. Both the test methods also require close loop servo controlled machine. The round panel test method (ASTM C1550) requires large size specimen and heavy steel supports prevents performing test in small laboratories. Split cylinder test (ASTM C496), do not necessarily reflect the true properties of the material as the specimen is forced to fail in the line of the application of the load and the test method is also not recommended by ACI for SFRC. In order to improve the material assessment procedure, the double Punch Test (DPT) introduced by Chen in 1970 [Chen, 1970] was extensively evaluated to develop a simple, quick and reliable testing method for SFRC. Various tests were carried out in order to evaluate peak and residual strength, stiffness, strain hardening and softening, toughness and other post crack properties. Our test results indicated that the DPT method could be immersed as reliable, easier and economical material test method. It could be used to distinguish the peak strength, residual strength, toughness stiffness and crack resistance, of different SFRC mixtures with less scatter results compared to other material test methods.
Download or read book Structural Applications of Steel Fiber Reinforced Concrete Analysis and Design written by Abdeslam Reklaoui and published by . This book was released on 1988 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Double punch Test for Evaluating the Performance of Steel Fiber reinforced Concrete written by Aaron Paul Woods and published by . This book was released on 2012 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study is to develop test protocols for comparing the effectiveness of fiber-reinforced concrete (FRC) mixtures with high-performance steel fibers. Steel fibers can be added to fresh concrete to increase the tensile strength, ductility, and durability of concrete structures. In order to quantify steel fiber-reinforced concrete (SFRC) mixtures for field applications, a material test capable of predicting the performance of SFRC for field loading conditions is required. However, current test methods used to evaluate the structural properties of FRC (such as residual strength and toughness) are widely regarded as inadequate; a simple, accurate, and consistent test method is needed. It was determined that the Double-Punch Test (DPT), originally introduced by Chen in 1970 for plain concrete, could be extended to fiber-reinforced concrete to satisfy this industry need. In the DPT, a concrete cylinder is placed vertically between the loading platens of the test machine and compressed by two steel punches located concentrically on the top and bottom surfaces of the cylinder. It is hypothesized that the Double-Punch Test is capable of comparing future fiber-reinforcement design options for use in structural applications, and is suitable for evaluating FRC in general. The DPT Research and Testing Program was administered to produce sufficient within-laboratory data to make conclusions and recommendations regarding the simplicity, reliability, and reproducibility of the DPT for evaluating the performance of SFRC. Several variables (including fiber manufacturer, fiber content, and testing equipment) were evaluated to verify the relevance of the DPT for FRC. In this thesis, the results of 120 Double-Punch Tests are summarized and protocols for its effective application to fiber-reinforced concrete are recommended. Also, fundamental data is provided that indicates the DPT could be standardized by national and international agencies, such as the American Society of Testing and Materials (ASTM), as a method to evaluate the mechanical behavior of FRC. This project is sponsored by the Texas Department of Transportation (TxDOT) through TxDOT Project 6348, "Controlling Cracking in Prestressed Concrete Panels and Optimizing Bridge Deck Reinforcing Steel," which is aimed at improving bridge deck construction through developments in design details, durability, and quality control procedures.
Download or read book Flexural Behavior of Steel fiber reinforced Concrete Beams written by Panat Kungsuwan and published by . This book was released on 2001 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flexural Behavior of Steel Fiber Reinforced Concrete SFRC written by Chun Nan Lim and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Constitutive Modeling and Flexural Analysis of Steel Fiber Reinforced Concrete for Structural Applications written by Cha-Don Lee and published by . This book was released on 1990 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ACI Structural Journal written by and published by . This book was released on 1988 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ductility of Steel Fiber Reinforced Concrete Connections Under Cyclic Loading written by Masoud Majd and published by . This book was released on 1978 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fiber Reinforcement in Prestressed Concrete Beams written by Hemant B. Dhonde and published by . This book was released on 2005 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ACI Materials Journal written by and published by . This book was released on 1989 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flexural fatigue behavior of steel fiber reinforced concrete written by Mahmoud Rida Galhoud and published by . This book was released on 1982 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Fiber Reinforced Concrete Connections for Precast Frames Under Reversed Cyclic Loading written by Rosa Maria Vasconez and published by . This book was released on 1997 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book PRO 31 International RILEM Workshop on Test and Design Methods for Steel Fibre Reinforced Concrete Background and Experiences written by Bernd Schnütgen and published by RILEM Publications. This book was released on 2003 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of the American Concrete Institute written by American Concrete Institute and published by . This book was released on 1983 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Each number includes "Synopsis of recent articles."
Download or read book A Standard Tensile Testing Procedure for Fiber reinforced Concrete FRC and Ultra high performance Fiber reinforced Concrete UHP FRC Based on Double Punch Test DPT written by Shuveksha Tuladhar and published by . This book was released on 2017 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current test methods such as ASTM 1609, ASTM 1550 and direct tensile test are used for evaluating the mechanical properties of Fiber Reinforced Concrete (FRC) and to determine the quality of mixture in design and construction practice. These test methods show high variability in the results, requires large specimen and complicated test setup. An ideal material test method for FRC should give consistent results in determining mechanical properties such as peak strength and residual strengths. Moreover, current test methods are expensive and time-consuming as more specimens are needed to acquire reliable test results. Double Punch Test (DPT) is a simple, reliable and consistent test method for evaluating the post-cracking behavior of FRC. DPT originally developed to determine the tensile strength of plain concrete, can also be used for evaluation of peak load and post-peak behavior of FRC and Ultra-High-Performance Fiber Reinforced Concrete (UHP-FRC). This method has a simple test setup and is easier to conduct in comparison to other test methods. DPT experimental test results are seen to be more consistent than the other test methods currently in practice. The simplicity of test setup, reliability of results (low scatter due to the higher cracking surface) and smaller specimens (fewer materials used) are the major advantages of using DPT method for evaluation of post cracking response of FRC and UHP-FRC. In this research, the application of double punch test is validated for FRC and the same method has been used and developed to confirm the suitability for UHP-FRC material in determining tensile strength and behavior in post cracking phase. However, there still exist some potential issue in the DPT method that needs to be resolved. The circumferential extensometer that is used to determine the total crack opening displacement in DPT is an expensive instrument. This limits the use of DPT method in most of the industrial and research laboratories. The measurement of crack width and inspection of a number of cracks are the important parameter for evaluating the characteristics of any concrete material. It is time-consuming to measure the crack width in a test by conventional visual inspection and automated crack width measurement is indispensable. This research mainly focuses on the deriving a simple formula for estimating average and maximum crack width using the axial deformation data and optimize the time taken for each DPT test. The relation would remove the need of using the expensive circumferential extensometer for the test. Thus, DPT could be used to evaluate and compare the quality of mixture for FRC and UHP-FRC by using a simple arrangement of LVDTs.
Download or read book The Flexural Behavior of Fiber Reinforced Concrete Beams written by Melvin R. Ramey and published by . This book was released on 1967 with total page 248 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 1994 with total page 1036 pages. Available in PDF, EPUB and Kindle. Book excerpt: