Download or read book Use of Structural Steel Diagonal Reinforcement in Coupling Beams written by Katharine Lai and published by . This book was released on 2002 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The hysteretic responses of the two specimens showed that the specimen containing the structural steel diagonal reinforcement had a higher ductility and was able to dissipate more energy than those using headed reinforcing bars or traditional hoops. This indicates that the use of structural steel is a viable alternative for the diagonal reinforcement of coupling beams. In addition, these results also demonstrated that the use of headed reinforcing bars as confinement for diagonal reinforcement is similar to, and therefore a feasible replacement for, diagonal reinforcement confined with closely spaced hoops." --

Download or read book Seismic Behavior of Coupling Beams with Multi hook Steel Fiber Reinforced Concrete written by Mohamed Al-Tameemi and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic design provisions in the ACI 318-19 Building Code for coupling beams with span-to-depth ratio ranging between 2.0 and 4.0 require to be designed either with heavily-confined diagonal reinforcement proportioned to resist the entire shear demand or as beams in Special Moment Resisting Frames. Although diagonally-reinforced coupling beams are labor-intensive and time-consuming to construct, they are the preferred reinforcement scheme selected by design engineers because of their seismic performance and higher allowable shear stress. Because of the difficulties associated with constructing diagonally-reinforced coupling beams, researchers and structural engineers paid attention to the use of steel fiber reinforcement to simplify reinforcement detailing in coupling beams. Results from research conducted in the past two decades (Setkit, 2012 and Pe̹rez-Irizarry, 2020) have indicated that it is possible to eliminate diagonal reinforcement in coupling beams with span-to-depth ratio greater than or equal to 2.0 when adding hooked steel fibers to the concrete mix. Three types of single-hook short (1.2 or 1.4 in.) steel fibers, mostly at a fiber volume content of 1.5%, were evaluated, which has imposed a significant limitation in the application of steel fiber reinforced concrete coupling beams. In this study, Twelve large-scale coupling beams were tested under displacement reversals. The coupling beams span-to-depth ratio was either 2.0, 2.25, or 3.0. Test specimens were designed to reach a peak shear stress ranging between 68́(f'c (psi) and 108́(f'c (psi). Two types of double-hook steel fibers, at fiber volume contents of 1.0% or 1.25%, were evaluated. These fibers are almost double the length and diameter of the steel fibers used in past studies. The use of larger fibers leads to a smaller number of fibers for a given fiber volume content, which facilitates concrete mixing and pouring. Further, the production cost of the double-hook steel fibers is less expensive compared to that of the short single-hook steel fibers.

Download or read book The Next Generation of Coupling Beams written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of experimental, parametric, and analytical studies was carried out to further the understanding of the behavior and constructability of coupled core wall (CCW) systems. Issues related to the design of wall piers in CCW systems and the beams used to couple the wall piers, structural response of the overall system, and construction difficulties arising from reinforcing steel congestion were explored. The research presented in this document focuses on a design approach of coupled core wall systems which concentrates on minimizing steel congestion while maintaining satisfactory structural behavior. To investigate the overall structural behavior of coupled core wall systems with wall piers and coupling beams designed based on the recommendations of this research, nonlinear time-history analyses were performed on two prototype structures. Both structures had the same plan dimensions, number of stories, slab thickness, wall thickness, and floor-to-floor heights. The first structure was designed using a steel coupling beam, and the second was designed using a diagonally-reinforced concrete coupling beam. The need for special boundary elements in the wall piers was based on maximum concrete compressive strains at design loads. Properties of the coupling beams used in the analyses of the two structures were based on measured behavior obtained during the experimental phase of the research.

Download or read book Large scale Testing of Steel reinforced Concrete SRC Coupling Beams Embedded Into Reinforced Concrete Structural Walls written by Christopher John Motter and published by . This book was released on 2014 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reinforced concrete structural walls provide an efficient lateral system for resisting seismic and wind loads. Coupling beams are commonly used to connect adjacent collinear structural walls to enhance building lateral strength and stiffness. Steel-Reinforced Concrete (SRC) coupling beams provide an alternative to reinforced concrete coupling beams, diagonally-reinforced for shorter spans and longitudinally-reinforced for longer spans, and offer potential advantages of reduced section depth, reduced congestion at the wall boundary region, improved degree of coupling for a given beam depth, and improved deformation capacity. Four large-scale, flexure-yielding, cantilever SRC coupling beams embedded into reinforced concrete structural walls were tested by applying quasi-static, reversed-cyclic loading to the coupling beam (shear) and the top of the wall (moment, shear, and constant axial load) to create cyclic tension and compression fields across the embedment region. The primary test variables were the structural steel section embedment length, beam span length (aspect ratio), quantities of wall boundary longitudinal and transverse reinforcement, and applied wall loading (moment, shear, and axial load). Based on test results, long embedment length, sufficient wall boundary reinforcement, and low-to-moderate wall demands across the embedment region are all associated with favorable coupling beam performance, characterized by minimal pinching and strength degradation in the load-deformation response and plastic hinge formation at the beam-wall interface with a lack of damage (plasticity) in the embedment region. The variation in aspect ratio was not found to significantly affect performance. Detailed design and modeling recommendations for steel reinforced concrete (SRC) coupling beams are provided for both code-based (prescriptive) design and alternative (non-prescriptive) design. For both code-based and alternative design, modeling a rigid beam for flexure and shear deformations with rotational springs at the beam-wall interfaces is recommended for stiffness, as test results indicate that the majority of the coupling beam deformations were associated with interface slip/extension. Alternative stiffness modeling recommendations are provided, in which an effective bending stiffness that accounts for the aspect ratio or beam length is used instead of interface rotational springs. A capacity design approach, in which the provided embedment strength exceeds the expected beam strength, is recommended for determining the required embedment length of the steel section into the structural wall. Recommendations for computing the nominal and expected (upper bound) flexure and shear strengths are provided. For alternative design, additional parameters are provided to define the strength and deformation capacity (to complete the backbone relations) and to address cyclic degradation for each of the test beams.

Download or read book Building Code Requirements for Structural Concrete ACI 318 08 and Commentary written by ACI Committee 318 and published by American Concrete Institute. This book was released on 2008 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: The quality and testing of materials used in construction are covered by reference to the appropriate ASTM standard specifications. Welding of reinforcement is covered by reference to the appropriate AWS standard. Uses of the Code include adoption by reference in general building codes, and earlier editions have been widely used in this manner. The Code is written in a format that allows such reference without change to its language. Therefore, background details or suggestions for carrying out the requirements or intent of the Code portion cannot be included. The Commentary is provided for this purpose. Some of the considerations of the committee in developing the Code portion are discussed within the Commentary, with emphasis given to the explanation of new or revised provisions. Much of the research data referenced in preparing the Code is cited for the user desiring to study individual questions in greater detail. Other documents that provide suggestions for carrying out the requirements of the Code are also cited.

Download or read book Seismic Response of Diagonally Reinforced Coupling Beams with Varied Hoop Spacings written by Brian Howard and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Reinforced concrete shear walls are commonly used seismic force-resisting systems in high-rise structures. Shear walls with regular openings for elevators or staircases at floor levels act as a system of two shear walls linked by concrete beams located above and below the openings. These shear wall systems are referred to as coupled walls. Ductile coupling beams are important components of ductile coupled walls due to their inherent high energy dissipation properties and stable failure mechanisms. Coupling beams with low span to depth ratios typically include diagonal reinforcement to resist shear and flexural forces induced by wind or seismic loads. In order to achieve the necessary ductility, the current CSA Standard A23.3-14 (CSA, 2014) limits the spacing between the buckling prevention ties (hoops) which confine the diagonal reinforcing bars to the lesser of 24dhoop, 6db or 100 mm. These stringent requirements for ductile diagonally reinforced coupling beams are commonly applied to moderately ductile and conventional construction cases. To simplify the construction of the coupling beams and provide realistic alternatives for the moderately ductile and conventional construction cases, the effect of an increased spacing of the buckling prevention ties in the coupling beams is investigated. Reversed cyclic loading tests were carried out on fifteen reinforcing bar specimens as well as four full-scale coupled shear wall specimens. The hysteretic response of the full-scale coupled wall specimens determined that an increased spacing of the buckling prevention ties performs adequately for the moderately ductile and conventional construction cases. Further research should be carried out to investigate the increase in resistance due to the longitudinal restraint of the coupling beams offered by the structure's floor slabs." --

Download or read book Plate Reinforced Composite Coupling Beams written by Wai-Yin Lam 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, "Plate-reinforced Composite Coupling Beams: Experimental and Numerical Studies" by Wai-yin, Lam, 林慧賢, 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 Plate-reinforced Composite Coupling Beams - Experimental and Numerical Studies Submitted by LAM Wai Yin for the degree of Doctor of Philosophy at The University of Hong Kong in October 2006 This thesis reports the results of experimental and numerical studies conducted on innovative plate-reinforced composite (PRC) coupling beams, designed with the objective of providing the construction industry with a feasible alternative coupling beam design that improves the structural performance of coupled shear wall structures under wind and seismic loading. The design of these coupling beams makes use of the composite action between structural steel and reinforced concrete (RC) by embedding a steel plate vertically into a conventional RC coupling beam. Shear studs were welded onto the steel plate surfaces in the beam span and the wall anchorage regions to enhance the plate/RC composite action. These studies build on the results of a previous experimental study conducted by the author on medium-length PRC coupling beams of span/depth ratio (l/h) 2.5. Three medium-length (l/h = 2.5) and three short (l/h = 1.17) PRC coupling beams were tested under reversed cyclic loading conditions. The results have demonstrated the effectiveness of both short and medium-length PRC coupling beams with properly designed plate anchorage in resisting large shear forces and withstanding large inelastic imposed deformations. It was found that shear studs in the wall regions would help to ensure ductile beam performance and desirable energy dissipation ability under seismic deformations, and that their absence would hinder the full strength development of short PRC coupling beams. A general pattern of bearing stress distributions with consistently large bearing stresses near the beam- wall joints and toward the ends of the plate anchors was also derived. i In order to extend the investigations to PRC coupling beams of different geometries and steel contents, so as to develop a comprehensive design procedure for the new type of coupling beams, the two-dimensional non-linear finite element analysis (NLFEA) program ATENA was employed. By introducing discrete bond and shear stud elements as the media for the plate/RC load transfers that allowed for interface slips, selected test specimens were first modelled and the reliability of the program in predicting the beam performances was verified. An extensive parametric study was then conducted on nearly one hundred PRC coupling beam models to investigate the effects of variations in span/depth ratios, reinforcement ratios and plate geometries on the load-rotation response under monotonically increasing loading. The internal load distributions were also investigated and the relationship between different force components on the plate anchors identified. These investigations indicated that if the walls were insufficiently reinforced or the plate anchorage was too short, the result would be the undesirable "strong beam - weak wall" phenomenon. Maximum allowable shear capacities and minimum required plate anchorage lengths were therefore proposed for PRC coupling beams to prevent early failure of wall piers. In the light of the experimental and the numerical observations, a bearing stress distribution model considering vertical and horizontal bearing forces was proposed for the plate anchors. An original and comprehen

Download or read book Earthquake Resistant Engineering Structures IX written by C. A. Brebbia and published by WIT Press. This book was released on 2013-07-08 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: In earthquake-prone regions of the world it is important not only to ensure that new facilities meet optimal standards but also that existing structures and infrastructure be retrofitted and rehabilitated. As world populations concentrate in urban areas, the stakes in human life and property of such natural disasters as earthquakes becomes higher and higher. This has been driving research on advances in the field. These advances are presented biennially at a conference organised by the Wessex Institute of Technology.The advances presented at the ninth conference in the series, which began in 1991 are presented in this book. The papers cover Plates and other geological risks; Earthquake prediction; Microzoning; Remote sensing / Monitoring / Early warning systems; Seismic codes; Seismic hazard and vulnerability; Tsunamis; Seismic isolation and energy dissipation; Structural dynamics; Building performance during earthquakes; Retrofitting; Lifelines; Material mechanics and characterisation; Nonlinear numerical analysis; Performance based design; Experimental studies; Forensic analysis; Safety and security; Socio-economic issues; Insurance related issues; Innovative technologies; Case studies.

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.

Download or read book Experimental Study on Embedded Steel Plate Composite Coupling Beams written by Wai-Yin Lam and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Experimental Study on Embedded Steel Plate Composite Coupling Beams" by Wai-yin, Lam, 林慧賢, 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 Experimental Study on Embedded Steel Plate Composite Coupling Beams Submitted by Lam Wai Yin for the degree of Master of Philosophy at The University of Hong Kong in April 2003 With the aim of providing the construction industry with a feasible alternative coupling beam design that improves the structural performance of coupled shear wall structures under wind and seismic loading, an experimental study has been conducted to study the effectiveness of embedded steel plate composite coupling beams, a recent design innovation. The design makes use of the composite action between structural steel and reinforced concrete by embedding a steel plate vertically into a conventionally reinforced concrete section containing longitudinal flexural and transverse shear reinforcement. The composite action is enhanced by shear studs welded onto the steel plate along the longitudinal direction close to the flexural reinforcement. Five coupling beam specimens with identical dimensions and a span/depth ratio of 2.5 were tested under reversed cyclic loading conditions. Two of the coupling beams were conventionally reinforced while the other three were embedded steel plate composite coupling beams, each with a vertically embedded steel plate spanning across the full span and being anchored in the wall piers. In order to investigate the effects of shear studs on the overall performance of the composite coupling beams, one of the composite coupling beams was embedded with a plain plate. The test results demonstrated the superior behaviour of embedded steel plate composite coupling beams over conventionally reinforced concrete coupling beams in respect of their strength, ductility, and energy dissipation capacities under elastic loading and inelastic deformations. A maximum average shear stress close to 10MPa and a maximum rotation ductility factor above 9 were respectively recorded in two embedded steel plate composite coupling beam specimens. It was also found that although embedding a steel plate in an RC coupling beam could increase both the initial stiffness and the loading capacity, shear studs must be provided to ensure the ductile performance of the composite coupling beams. Simple theories have been developed for calculating the beam capacity, the shares of loading between the steel plate and the reinforced concrete in an embedded steel plate composite coupling beam, the beam moment-curvature relationship, and the initial beam stiffness. These theories enabled experimental results to be predicted with a high degree of accuracy. Pullout tests were also carried out to study the respective contributions to the composite action of the shear studs and the natural bonding between an embedded steel plate and its surrounding reinforced concrete. Based on the experimental results and the reviews of previous studies on shear studs and reinforced concrete beams with bolted side steel plates, a design procedure of the shear stud arrangement in the beam span has been proposed. DOI: 10.5353/th_b2664335 Subjects: Plate girders - Testing Concrete beams - Testing Concrete beams - Design and construction

Download or read book Experimental Study on Seismic Performance of Reinforced Concrete Coupling Beams and Rectangular Squat Walls with Innovative Reinforcement Configurations written by Poorya Hajyalikhani and published by . This book was released on 2016 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reinforced concrete core walls, coupled by diagonally reinforced coupling beams (DCBs), are a very efficient seismic force resisting system for medium- to high-rise buildings. The diagonal reinforcing bars in DCBs are most effective when the beam has a span-to-depth ratio, ln/h, less than 2. Modern construction, due to architectural requirements, typically requires span-to-depth ratios between 2.4 to 4, which leads to a very shallow angle of inclination of the diagonal reinforcement (generally between 10 to 20 degrees). The lower angles of inclination, combined with the detailing requirements specified in ACI 318, results in reinforcement congestion as well as design and construction difficulties. These issues with DCBs can be considerably minimized by utilizing an innovative and simplistic reinforcing scheme as investigated in this study. This reinforcement scheme consists of two separate cages similar to those used for typical beams in RC special moment frames. The proposed coupling beam has high elastic stiffness and acts like a conventional coupling beam under small displacements. Upon large displacements, cracks begin developing at the mid-span and mid-height of the beams where the narrow gap is located, gradually propagating towards the beam's ends. The cracks eventually separate the coupling beam into two slender beams where each has nearly twice the aspect ratio of the original coupling beam. This essentially transforms the shear-dominated behavior into a flexure-dominated behavior, as conventional slender beams. Because damage initiates from the center of the beam; then spreads towards the ends, the beam's ends maintain their integrity even under very large displacements, thereby eliminating the sliding shear failure at the beam-to-wall interface. Preliminary testing results on half-scale coupling beam specimens with span-to-depth ratio of 2.4 showed that coupling beams with the proposed reinforcement scheme were able to sustain high shear stresses and large rotations before strength degradation occurred. Subsequently, six rectangular squat wall specimens with height-to-length ratio 0.5 and 1, which were designed based the second innovative design concept using discrete confining cages to reinforce the web of the walls, were tested under lateral displacement reversals. Each wall consisted of several separate cages similar to those used for typical beams in RC special moment frames. The response of squat wall specimens showed very high shear strength and stiffness, while maintain adequate ductility due to well confinement of the wall.

Download or read book Seismic Design of Reinforced Concrete and Masonry Buildings written by Thomas Paulay and published by Wiley-Interscience. This book was released on 1992-04-10 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasizes actual structural design, not analysis, of multistory buildings for seismic resistance. Strong emphasis is placed on specific detailing requirements for construction. Fundamental design principles are presented to create buildings that respond to a wide range of potential seismic forces, which are illustrated by numerous detailed examples. The discussion includes the design of reinforced concrete ductile frames, structural walls, dual systems, reinforced masonry structures, buildings with restricted ductility and foundation walls. In addition to the examples, full design calculations are given for three prototype structures.

Download or read book Fibre reinforced concrete From design to structural applications written by FIB - Féd. Int. du Béton and published by FIB - Féd. Int. du Béton. This book was released on 2016 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: The FRC-2014 Workshop Fibre Reinforced Concrete: from Design to Structural Applications was the first ACI-fib joint technical event. The Workshop, held at Polytechnique Montreal (Canada) on July 24th and 25th 2014, was attended by 116 participants from 25 countries and 4 continents. The first international FRC workshop was held in Bergamo (Italy) in 2004. At that time, the lack of specific building codes and standards was identified as the main inhibitor to the application of this technology in engineering practice. Ten years after Bergamo, many of the objectives identified at that time have been achieved. The use of fibre reinforced concrete (FRC) for designing structural members in bending and shear has recently been addressed in the fib Model Code 2010. Steel fibre reinforced concrete (SFRC) has also been used structurally in several building and bridge projects in Europe and North-America. SFRC has been widely used in segmental tunnel linings all over the world. Members of ACI544 and fib TG-4.1 have been involved in writing code based specifications for the design of FRC structural members. More than fifty papers were presented at the Workshop from which forty-four were selected for this joint ACI/fib publication. The papers are organised in the document under six themes: Design guidelines and specifications, Material properties for design, Behaviour and design of beams and columns, Behaviour and design of slabs and other structures, Behaviour and design of foundations and underground components, and finally, Applications in structure and underground construction projects.

Download or read book Earthquake Engineer 10th World written by and published by Taylor & Francis US. This book was released on 1992-01-01 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nonlinear Modeling Parameters for Diagonally Reinforced Concrete Coupling Beams written by Dakota B. Saathoff and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A database of diagonally reinforced concrete coupling beam tests was formulated and used to assess strength, stiffness, and deformation capacity. The shear strength equation provided in ACI 318-19 considers only the transverse strength of the diagonal bars and was found to be overly conservative. A new equation that includes shear strength of concrete and transverse reinforcement was found to provide a better fit to test data. Existing recommendations were found to underestimate deformation capacity. A plastic hinge model that includes bond slip was formulated to estimate deformation capacity based on strain at crushing of confined concrete and strain at onset of diagonal reinforcement buckling. Favorable agreement was found between the model and test data. An empirical equation based on ratio of diagonal bar diameter to section depth, db/h, and ratio of spacing of transverse reinforcement to diagonal bar diameter, s/db, was fit to data. The empirical equation led to reduced scatter relative to the plastic hinge model. A parametric study was conducted using the plastic hinge model and the empirical equation, and reasonable agreement was found between the two models over this practical range of parameters. New recommendations for determining the deformation capacity of diagonally reinforced concrete coupling beams are provided.

Download or read book Experimental Study of Reinforced Concrete Coupling Beams with Axial Restraint written by Bahaa Ahmad Burhan Al-Khateeb and published by . This book was released on 2021 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coupled shear walls are a lateral load resisting system used in buildings to resist seismic and wind loads. In coupled walls, coupling beams span between adjacent shear walls and are typically located at floor level. Coupling beams are designed to yield and form plastic hinges before the wall piers. Damage patterns observed after the 2010-2011 Canterbury earthquake sequence in New Zealand showed instances in which coupled walls did not behave as intended in design, as plastic hinges formed at the base of the wall piers but not at the beam ends. The Canterbury Earthquakes Royal Commission suggested that this undesirable response may have been caused by coupling beam axial restraint from walls and floors increasing the strength of the coupling beams.To better understand the effect of axial restraint on coupling beam behavior, seven one-half-scale reinforced concrete coupling beams were designed using ACI 318-19 and were constructed and tested. The main test variables were span-to-depth ratio, reinforcement configuration (conventional or diagonal), primary reinforcement ratio and bar diameter, and level of axial restraint. Six beams consisted of three identical pairs, with the two beams in each pair tested at a different level of constant stiffness axial restraint.Test results indicated that axial restraint, which is not included in the ACI 318-19 equation for nominal shear strength of diagonally reinforced coupling beams, increased the beam strength. Axial restraint also influenced the load-displacement responses of the beams and the observed damage patterns. The conventionally reinforced beams were observed to yield in shear, while damage concentrated at the ends of the diagonally reinforced beams. The onset of significant strength degradation in the diagonally reinforced beams was associated with buckling of diagonal reinforcement rather than crushing of confined concrete, such that variation in axial compression on identical pairs of beam did not lead to a significant difference in deformation capacity. Test beams with #6 diagonal reinforcement had improved deformation capacity over those with #4 diagonal reinforcement, due to the influence of the ratio of transverse reinforcement spacing to diagonal bar diameter (s/db) on bar buckling.

Download or read book Reinforced Concrete Structures written by Robert Park and published by John Wiley & Sons. This book was released on 1991-01-16 with total page 794 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sets out basic theory for the behavior of reinforced concrete structural elements and structures in considerable depth. Emphasizes behavior at the ultimate load, and, in particular, aspects of the seismic design of reinforced concrete structures. Based on American practice, but also examines European practice.