Seismic Demands In Precast Concrete Diaphragms PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Seismic Demands In Precast Concrete Diaphragms PDF full book. Access full book title Seismic Demands In Precast Concrete Diaphragms.
| Author | : Matthew John Schoettler |
| Publisher | : |
| Total Pages | : 734 |
| Release | : 2010 |
| Genre | : |
| ISBN | : 9781124100968 |
Download Seismic Demands in Precast Concrete Diaphragms Book in PDF, ePub and Kindle
Existing methods of analyzing lateral force demands on structures during seismic events do not fully contemplate the amplification caused by diaphragm flexibility. Moreover, commonly used code provisions do not conservatively anticipate floor demands generated in shear wall buildings. In buildings with floors that act as rigid diaphragms, elastic response necessitates the accurate estimation of design forces, which is currently not provided with an equivalent lateral force analysis. In long span structures with perimeter walls, diaphragm flexibility may result in amplified floor demands. This amplification was addressed while investigating elastic diaphragm demands in precast concrete buildings. Modal response spectrum analysis formulated the basis of the elastic design. A modified version of the modal first mode reduced method proposed by Rodríguez et al. (2002) was extended to shear wall buildings with diaphragm flexibility. This method conservatively estimates the design forces necessary for elastic diaphragm response at the design earthquake hazard. Diaphragm demands were assessed in a large scope analytical with the proposed design method. Results show this method sufficiently bounds demands for rigid floor systems or for systems whose flexibility is included. An experimental program supported the analytical study providing in-plane diaphragm stiffness characteristics of a precast concrete building. A complete structural system was tested at 54% scale with unique diaphragm systems on each of its three floors. Hybrid rocking walls minimized residual drift and allowed customized nonlinear wall behavior at different hazards. Extensive testing and abundant instrumentation generated valuable information regarding the seismic performance of precast concrete systems. These results provided the necessary mechanism for analytical model validation and insight on precast concrete diaphragm behavior.
| Author | : Dichuan Zhang |
| Publisher | : |
| Total Pages | : 620 |
| Release | : 2010 |
| Genre | : |
| ISBN | : |
Download EXAMINATION OF PRECAST CONCRETE DIAPHRAGM SEISMIC RESPONSE BY THREE-DIMENSIONAL NONLINEAR TRANSIENT DYNAMIC ANALYSES. Book in PDF, ePub and Kindle
The primary objective of the dissertation research is to establish the seismic demands of precast concrete floor diaphragms designed with an emerging design methodology. To accomplish this, three-dimensional (3D) finite element (FE) models of diaphragm-sensitive precast concrete structures have been developed by extending two-dimensional (2D) diaphragm model developed previously for nonlinear static "pushover" analyses. Using these models, diaphragm seismic demands under expected hazard are evaluated through the nonlinear transient dynamic analyses (NLTDA). The research work is composed of four major parts:(1) Developing 3D NLTDA analytical model for diaphragm-sensitive precast concrete structures: The 3D structure model is extended from a 2D FE diaphragm model developed by a previous researcher. This process involves properly handling comparability conditions in 3D, incorporating proper hysteresis behavior for the diaphragm reinforcement, and developing appropriate lateral force resisting system (LFRS) models. A sensitivity analysis is performed for 3D NLTDA modeling to assist in creating an appropriate model.(2) Application of the model in integrated analysis-driven physical testing: These experiments occurred at Lehigh University (LU) with project collaborators. The loading in these tests were controlled by NLTDA of the 3D analytical model. The tests were used to examine the seismic response of key joints (critical flexure and shear joints) in the diaphragm under realistic demands and to further calibrate the analytical model.(3) Analytical modeling in support of shake table testing: The shake table test was performed at University of California San Diego (UCSD). The test involved a half scale three-story diaphragm-sensitive precast concrete structure. NLTDA using the 3D analytical model is used to assist in design and performance prediction of the test specimen. The test results are being used to calibrate/verify the analytical model.(4) Calibrating design factors for the emerging diaphragm design methodology: In the last research step, the 3D analytical model is used to calibrate trial design factors for the emerging diaphragm design methodology. These factors are established based on a parametric study of NLDTA at different seismic hazard levels using simple structure configurations. These factors will be evaluated on models of realistic structures to determine design factors for the final design procedure.
| Author | : Ge Wan |
| Publisher | : |
| Total Pages | : 434 |
| Release | : 2008 |
| Genre | : |
| ISBN | : |
Download Analytical Development of Capacity Design Factors for a Precast Concrete Diaphragm Seismic Design Methodology Book in PDF, ePub and Kindle
The primary objective of the dissertation work is to examine the capacity of precast concrete diaphragms. This work is part of a multi-university research effort to develop a new seismic design methodology for precast/prestressed concrete floor diaphragms. To accomplish this, two-dimensional finite element (FE) models of precast floor diaphragms are created, including new elements to match the response of reinforcing details under combined forces. Using these models, nonlinear static"pushover"analyses are performed by applying body forces in the plane of the floor. The analyses are composed of three major parts:(1) Parametric studies to determine the required diaphragm shear strength relative to design (flexural) strength, termed"shear reinforcement overstrength", to promote a ductile mechanism in precast diaphragms. The performance of precast diaphragms with different shear reinforcement overstrength is examined. Appropriate shear reinforcement overstrength design factors are proposed to produce certain performance targets, in terms of a number of key parameters related to diaphragm geometry and the properties of the diaphragm reinforcing details.(2) Parametric studies to examine the effects of"secondary"diaphragm elements (spandrels, internal beams) on precast diaphragm behavior. Though not directly counted in design to participate diaphragm action, the secondary elements and their connections to the main diaphragm may modify the strength, stiffness and deformation capacity of the diaphragm. Analytical studies are performed to examine their effect on the global characteristics and local demands of precast floor diaphragms. The parameters evaluated include the characteristics of the connection details, the seismic hazard level used in design, diaphragm geometry, and layouts of spandrels and internal beams.(3) Development of a rational method for calculating the service stiffness and yield strength of precast concrete diaphragms. The method involves input of diaphragm geometry andreinforcing details. The method is verified analytically through comparisons to a set of FE analyses for an idealized diaphragm representation (regular single span diaphragm idealized with simple end supports). The method verified for a single set of diaphragm reinforcement details is used to estimate the properties over a range of untopped and topped diaphragm systems. Consideration of spandrel and internal beams in the method is discussed.
| Author | : fib Fédération internationale du béton |
| Publisher | : fib Fédération internationale du béton |
| Total Pages | : 272 |
| Release | : 2003-01-01 |
| Genre | : Technology & Engineering |
| ISBN | : 9782883940673 |
Download Seismic Design of Precast Concrete Building Structures Book in PDF, ePub and Kindle
The aim of this state-of-art report is to present current practices for use of precast and prestressed concrete in countries in seismic regions, to recommend good practice, and to discuss current developments. The report has been drafted by 30 contributors from nine different countries. This state-of-art report covers: state of the practice in various countries; advantages and disadvantages of incorporating precast reinforced and prestressed concrete in construction; lessons learned from previous earthquakes; construction concepts; design approaches; primary lateral load resisting systems (precast and prestressed concrete frame systems and structural walls including dual systems) diaphragms of precast and prestressed concrete floor units; modelling and analytical methods; gravity load resisting systems; foundations; and miscellaneous elements (shells, folded plates, stairs and architectural cladding panels). Design equations are reported where necessary, but the emphasis is on principles. Ordinary cast-in-place reinforced concrete is not considered in this report. This fib state-of-the-art report is intended to assist designers and constructors to provide safe and economical applications of structural precast concrete and at the same time to allow innovation in design and construction to continue. This Bulletin N° 27 was approved as an fib state-of-art report in autumn 2002 byfib Commission 7, Seismic design.
| Author | : Wei Zheng |
| Publisher | : |
| Total Pages | : 334 |
| Release | : 2001 |
| Genre | : |
| ISBN | : |
Download Analytical Method for Assessment of Seismic Shear Capacity Demand for Untopped Precast Double-tee Diaphragms Joined by Mechanical Connectors Book in PDF, ePub and Kindle
| Author | : FIB – Féd. Int. du Béton |
| Publisher | : FIB - Féd. Int. du Béton |
| Total Pages | : 290 |
| Release | : 2016 |
| Genre | : Technology & Engineering |
| ISBN | : 2883941181 |
Download Precast-concrete buildings in seismic areas Book in PDF, ePub and Kindle
This document has a broad scope and is not focussed on design issues. Precast construction under seismic conditions is treated as a whole. The main principles of seismic design of different structural systems, their behavior and their construction techniques are presented through rules, construction steps and sequences, procedures, and details that should lead to precast structures built in seismic areas complying with the fundamental performance requirements of collapse prevention and life safety in major earthquakes and limited damage in more frequent earthquakes. The content of this document is largely limited to conventional precast construction and, although some information is provided on the well-known “PRESSS technology” (jointed ductile dry connections), this latter solution is not treated in detail in this document. The general overview, contained in this document, of alternative structural systems and connection solutions available to achieve desired performance levels, intends to provide engineers, architects, clients, and end-users (in general) with a better appreciation of the wide range of applications that modern precast concrete technology can have in various types of construction from industrial to commercial as well as residential. Lastly, the emphasis on practical aspects, from conceptual design to connection detailing, aims to help engineers to move away from the habit of blindly following prescriptive codes in their design, but instead go back to basic principles, in order to achieve a more robust understanding, and thus control, of the seismic behaviour of the structural system as a whole, as well as of its components and individual connections.
| Author | : ACI-ASCE Committee 550 |
| Publisher | : |
| Total Pages | : |
| Release | : 2018-09 |
| Genre | : |
| ISBN | : 9781641950275 |
Download ACI 550. 5M-18 Code Requirements for the Design of Precast Concrete Diaphragms for Earthquake Motions (ACI 550. 5M-18) and Comment Book in PDF, ePub and Kindle
| Author | : Joint ACI-ASCE Committee 550 |
| Publisher | : |
| Total Pages | : 24 |
| Release | : 2018-06 |
| Genre | : |
| ISBN | : 9781641950176 |
Download ACI 550. 5-18 Code Requirements for the Design of Precast Concrete Diaphragms for Earthquake Motions (ACI 550. 5-18) and Commentar Book in PDF, ePub and Kindle
| Author | : Brandon Cook |
| Publisher | : |
| Total Pages | : 0 |
| Release | : 2021 |
| Genre | : |
| ISBN | : |
Download Precast Concrete Diaphragm Design by ASCE 7-16 Book in PDF, ePub and Kindle
Floor and roof diaphragms are an important aspect of a building's structural lateral system. The diaphragm resists in-plane seismic loads and transfers them to the vertical lateral force resisting system. If they are not properly designed, the failure could be devastating. After the 1994 Northridge earthquake the failures of multiple precast structures were investigated, and it was determined that inadequate diaphragm design was the cause of the failures. It was found that previous code provisions underestimated the diaphragm design forces. Additionally, diaphragms were assumed to behave elastically during seismic events, but it was observed that a large earthquake could cause inelastic behavior of diaphragms. Code provisions prior to the ASCE 7-16 determined diaphragm design forces based solely on the fundamental modal response of structures. However, further research proved that higher modes also influenced diaphragm forces. Therefore, a change was warranted to diaphragm design provisions in the ASCE 7-16. The diaphragm design provisions in the ASCE 7-16 ensure adequate ductility and strength of diaphragms and provides different options for elastic or inelastic diaphragm design. Not all design options are applicable and permitted for every scenario. The selection of the design option will depend on the seismic design category, the geometry of the diaphragm, and the number of stories of the building. The new diaphragm design provisions in the ASCE 7-16 are required for precast diaphragm design. This report provides a detailed design procedure for precast diaphragms and briefly discusses the research done on precast diaphragms that led to the provisions in the ASCE 7-16. In addition, a parametric study was conducted to illustrate how the design options change the diaphragm design forces and required reinforcement.
| Author | : |
| Publisher | : |
| Total Pages | : 224 |
| Release | : 2019-03 |
| Genre | : |
| ISBN | : 9781943961450 |
Download Design Guide for Reinforced Concrete Diaphragms Book in PDF, ePub and Kindle
This guide is the definitive resource on the design and detailing of diaphragms in cast-in-place reinforced concrete buildings. The requirements in ACI 318-14 are clearly summarized in figures and tables for quick reference. Comprehensive methods are provided on how to (1) determine diaphragm thickness based on strength and serviceability requirements; (2) calculate in-plane and collector forces based on ASCE/SEI 7-16 requirements; (3) model and analyze diaphragms; (4) determine the required reinforcement based on two different types of common construction methods; and (5) economically detail the required reinforcement based on the latest ACI 318 requirements. A step-by-step design procedure is provided that can be used for buildings assigned to Seismic Design Categories A through F. Numerous design aids and worked-out examples illustrate the code requirements for low-, mid-, and high-rise buildings, including buildings with irregularities.
