Download or read book Behavior of Coupling Beams Under Load Reversals written by and published by . This book was released on 1980 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Behaviour of Coupling Beams Under Load Reversals written by Portland Cement Association. Research and Development. Construction Technology Laboratories and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Behavior of Steel Fiber reinforced Concrete Coupling Beams Without Diagonal Bars written by Angel Luis Perez Irizarry and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Medium- to high-rise buildings in regions of high seismicity in the USA often rely on coupled wall systems for lateral load resistance. The strength, stiffness, as well as deformation and energy dissipation capacities of coupling beams greatly influence the response of coupled wall systems. However, the high shear stresses and deformation demands coupling beams are expected to sustain during strong ground motions require the use of complex reinforcement detailing that includes large amounts of transverse and diagonal reinforcement, which makes them difficult and time-consuming to construct. Previous studies have shown that the use of a tensile strain-hardening, steel fiber-reinforced concrete (SFRC) reinforced with high-strength (330 ksi) hooked fibers at a 1.5% volume fraction allowed significant reductions of transverse reinforcement and the elimination of diagonal bars in coupling beams with span-to-depth ratios of 2.2 or greater. Despite the substantial reinforcement reduction and observed adequate coupling beam behavior, the use of SFRCs for coupling beam design has been limited in practice, in part due to experimental data on the behavior of SFRC coupling beams without diagonal bars being limited to a single fiber type and dosage. In this study, the behavior of SFRC coupling beams without diagonal bars, constructed with various SFRCs, was experimentally investigated. To this end, eight large-scale precast SFRC coupling beams without diagonal bars were tested under large displacement reversals. The main experimental variables considered were coupling beam span-to-depth ratio (3.0 and 2.0) and peak shear stress [7 to 12 [sqrt]f'[c]], fiber type, and fiber dosage. Three different hooked steel fibers and fiber volume fractions (1.0, 1.25, and 1.50%) were considered in this study for a total of six different SFRCs. Test results showed that coupling beams without diagonal bars can achieve drift capacities exceeding 5% while subjected to peak shear stresses between 6 and 10 [sqrt]f'[c]. Based on results from this and previous investigations, performance criteria for SFRCs based on ASTM C1609-12 test results were proposed. The proposed SFRC performance criteria were tied to coupling beam span-to-depth ratio and peak shear stress demand to achieve a target coupling beam drift capacity of 6%. Additionally, design recommendations that include reinforcement detailing, calculation of flexural and shear strength, and a lumped plasticity model for simulating the shear versus drift envelope response of SFRC coupling beams were proposed. The proposed model accounts for inelastic flexural rotations, concentrated rotations due to reinforcement slip, and shear sliding. The simple model showed good agreement with experimental results from this and other studies.

Download or read book Behavior of Coupling Beams Under Land Reversals written by G. B. Barney and published by . This book was released on 1980 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Behaviour of Reinforced Concrete Beams Under Load Reversals written by Sait Toprak and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NEHRP Commentary on the Gidelines for the Seismic Rehabilitation of Buildings written by Eugene Zeller and published by DIANE Publishing. This book was released on 2000-06 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document from the National Earthquake Hazards Reduction Program (NEHRP) was prepared for the Building Seismic Safety Council (BSSC) with funding from the Federal Emergency Management Agency (FEMA). It provides commentary on the NEHRP Guidelines for the Seismic Rehabilitation of Buildings. It contains systematic guidance enabling design professionals to formulate effective & reliable rehabilitation approaches that will limit the expected earthquake damage to a specified range for a specified level of ground shaking. This kind of guidance applicable to all types of existing buildings & in all parts of the country has never existed before. Illustrated.

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 The Seismic Design Handbook written by Farzad Naeim and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook contains up-to-date existing structures, computer applications, and infonnation on planning, analysis, and design seismic design of wood structures. A new and very useful feature of this edition of earthquake-resistant building structures. Its intention is to provide engineers, architects, is the inclusion of a companion CD-ROM disc developers, and students of structural containing the complete digital version of the handbook itself and the following very engineering and architecture with authoritative, yet practical, design infonnation. It represents important publications: an attempt to bridge the persisting gap between l. UBC-IBC (1997-2000) Structural advances in the theories and concepts of Comparisons and Cross References, ICBO, earthquake-resistant design and their 2000. implementation in seismic design practice. 2. NEHRP Guidelines for the Seismic The distinguished panel of contributors is Rehabilitation of Buildings, FEMA-273, Federal Emergency Management Agency, composed of 22 experts from industry and universities, recognized for their knowledge and 1997. extensive practical experience in their fields. 3. NEHRP Commentary on the Guidelinesfor They have aimed to present clearly and the Seismic Rehabilitation of Buildings, FEMA-274, Federal Emergency concisely the basic principles and procedures pertinent to each subject and to illustrate with Management Agency, 1997. practical examples the application of these 4. NEHRP Recommended Provisions for principles and procedures in seismic design Seismic Regulations for New Buildings and practice. Where applicable, the provisions of Older Structures, Part 1 - Provisions, various seismic design standards such as mc FEMA-302, Federal Emergency 2000, UBC-97, FEMA-273/274 and ATC-40 Management Agency, 1997.

Download or read book Influence of Coupling Beam Axial Restraint on Analysis and Design of Reinforced Concrete Coupled Walls written by Kamiar Kalbasi Anaraki and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reinforced concrete coupled shear walls are effective systems for resisting lateral loads, often used in mid to high-rise buildings in earthquake-prone areas. These walls usually feature openings for doors and windows, dividing a solid wall into two separate piers. The strength of these walls comes not just from the sum of two individual piers, but from wall piers cross-section and the framing action between the wall piers through the coupling beams. In an earthquake, coupling beams serve as fuse elements, distributing seismic energy throughout the height of the building. This not only reduces the bending stress at the base of the shear walls but also improves their overall strength, stiffness, and resistance to lateral forces. Properly designed coupling beams, with sufficient longitudinal, diagonal, and confinement reinforcement, can effectively absorb energy while maintaining significant strength and stiffness, even under large deformations.The objective of this study was to develop, calibrate, and validate a new coupling beam model that integrates axial and lateral interactions under cyclic loading conditions. This model aims to reliably predict the elastic and inelastic responses of diagonally reinforced coupling beam elements. The proposed analytical model incorporates a fiber-based concrete cross-section, and diagonal trusses to account for axial interactions between the nonlinearity in the steel and concrete along the beam's length. This feature allows the model to capture additional axial force developed in the element due to the axial restraint from the wall piers, thereby increasing or decreasing the lateral strength of the beam. Additionally, the model includes the slip-extension behavior between the coupling beam and the supporting wall through zero-length fiber-based elements at both ends of the beam. Finally, with the development of the new analytical model and recent advancements in understanding the shear strength of RC shear walls, a new coupled/core wall design approach has been introduced to optimize the design of RC core walls. A variety of archetypes have been designed, based on both current design practices and the proposed approach. Detailed analytical models have been developed, and the efficiency of the proposed design has been evaluated through nonlinear static and dynamic analyses. To conduct the dynamic analysis, suites of ground motions were selected using the CMS approach and scaled to the MCER level of hazard. It has been demonstrated that the designed archetypes based on proposed procedure provide a more reliable shear responses under seismic loading compared to current design practices.

Download or read book Advanced Methods for Seismic Performance Evaluation of Building Structures written by Sang Whan Han and published by MDPI. This book was released on 2021-01-21 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue was created to collect the most recent and novel research on seismic performance evaluation of building structures. This issue includes three important topics on seismic engineering for building structures: (1) seismic design and performance evaluation, (2) structural dynamics, and (3) seismic hazard and risk analysis. To protect building structures from earthquakes, it is necessary to conduct seismic performance evaluations on structures with reliable methods and to retrofit these structures appropriately using the results of the seismic performance evaluation.

Download or read book Proceedings fib Symposium in Athens Greece written by FIB – International Federation for Structural Concrete and published by FIB - Féd. Int. du Béton. This book was released on 2003-05-01 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Behavior of High performance Fiber Reinforced Cementitious Composite Coupling Beams written by Bekir Afsin Canbolat and published by . This book was released on 2004 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Collapse Assessment of Reinforced Concrete Coupled Walls written by Negin Aryaee Tauberg and published by . This book was released on 2019 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT OF THE DISSERTATION Collapse Assessment of Reinforced Concrete Ductile Coupled Walls by Negin Aryaee Tauberg Doctor of Philosophy in Civil Engineering University of California, Los Angeles, 2019 Professor John Wright Wallace, Chair Reinforced concrete coupled shear walls are efficient lateral load resisting systems commonly constructed as part of core walls in mid to high-rise buildings. Coupled walls are constructed as a result of openings accommodating doorways and windows, thus separating a solid wall segment in two piers. Instead of summing the strength of two individual wall piers, the efficiency of the individual wall piers is improved by proper coupling of two adjacent walls linked by coupling beams. During earthquake shaking, coupling beams act as ductile fuses and dissipate seismic energy over the building height. This coupling action reduces the flexural demand at the base of the shear walls and results in increased strength, stiffness, and lateral load resistance. Coupling beams can dissipate energy well in the system and retain significant strength and stiffness through large displacement reversals when they are detailed to retain ductility with adequate longitudinal, diagonal, and confinement reinforcement. As part of this study, important parameters affecting the behavior of coupling beams and coupled wall systems are assessed. A thorough coupling beam database is compiled consisting of 104 individual beam specimen and 11 coupled wall system level tests. The database is used to derive trends for coupling beam effective stiffness and shear-deformation backbone relations. Based on a review of past experimental results, an expression is derived relating the coupling beam effective stiffness as a function of the beam aspect ratio, i.e., EcIeff/EcIg = 0.07ln/h, which represents the secant stiffness to yield and includes the stiffening impact of the slab and the post- tensioning stress. This expression has been adopted in the PEER TBI (2017) and LATBSDC (2017) guidelines. Experimental shear-deformation information from the database is also used to quantify plastic rotations at peak coupling beam shear strength and at strength loss. The subsequent part of this study focuses on proposing appropriate seismic response parameters for coupled wall systems. Current ASCE 7-16 and ACI 318-14 design provisions specify the same seismic response parameters to be used for coupled walls as are for special structural walls. However, well-designed coupled walls can have improved lateral performance and energy dissipation compared to uncoupled walls since part of the total overturning moment is resisted by coupling action and energy dissipation is distributed along the height of structure. In coordination with ASCE 7 and ACI 318, a new lateral system is introduced for Reinforced Concrete (RC) Ductile Coupled Walls as an assembly of walls with aspect ratio (hwcs/lw) greater than 2.0 which are linked by coupling beams having aspect ratios (ln/h) between 2.0 and 5.0. This study employs the FEMA P695 methodology to validate the proposed response modification factor of R = 8, deflection amplification factor of Cd = 8, and an overstrength factor of 0 = 2.5 for RC Ductile Coupled Walls. The collapse assessment studies include forty-one Archetypes designed using ASCE 7-16 and ACI 318-19 including new provisions that require wall shear amplification and a drift capacity check. The Archetypes vary in building height (6 to 30 stories), wall cross section (planar and flanged/core), coupling beam aspect ratio (ln/h = 2.0 to 5.0), and coupling beam reinforcement arrangement (conventionally reinforced and diagonally reinforced). Collapse of the Archetypes is evaluated using failure criteria models that account for flexural failure (concrete crushing, bar buckling, wall lateral instability, bar fracture), shear, and axial failures. In comparison to previous studies that have assumed failure to occur at a roof drift ratio of 5%, this study uses a conservative approach to define flexural failure as a 20% drop in lateral strength. Overall, nonlinear static pushover and incremental dynamic analysis results indicate that R = 8 and 0 = 2.5 are appropriate parameters for RC Ductile Coupled Wall systems that are designed per ASCE 7-16 and ACI 318-19 provisions.

Download or read book Advances in Building Technology written by M. Anson and published by Elsevier. This book was released on 2002-11-14 with total page 1844 pages. Available in PDF, EPUB and Kindle. Book excerpt: This set of proceedings is based on the International Conference on Advances in Building Technology in Hong Kong on 4-6 December 2002. The two volumes of proceedings contain 9 invited keynote papers, 72 papers delivered by 11 teams , and 133 contributed papers from over 20 countries around the world. The papers cover a wide spectrum of topics across the three technology sub-themes of structures and construction, environment, and information technology. The variety within these categories spans a width of topics, and these proceedings provide readers with a good general overview of recent advances in building research.

Download or read book Proceedings of the Canadian Society of Civil Engineering Annual Conference 2022 written by Rishi Gupta and published by Springer Nature. This book was released on 2023-08-05 with total page 1180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises the proceedings of the Annual Conference of the Canadian Society of Civil Engineering 2022. The contents of this volume focus on specialty conferences in construction, environmental, hydrotechnical, materials, structures, transportation engineering, etc. This volume will prove a valuable resource for those in academia and industry.

Download or read book Cyclic Dowel Action and Pull out Behavior of Beam Reinforcement at Reinforced Concrete Joints written by Kienuwa Obaseki and published by . This book was released on 1985 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.