EXTENDING THE COLLAPSE TIME OF NON-ENGINEERED MASONRY BUILDINGS UNDER SEISMIC LOADING
Author: J. Macabuag and S. Bhattacharya | Size: 3.1 MB | Format:PDF | Quality:Unspecified | Publisher: EWB-UK Research Conference 2009 Hosted by The Royal Academy of Engineering February 20 | Year: 2009 | pages: 14
THE COLLAPSE OF NON-ENGINEERED MASONRY IS ONE OF THE GREATEST CAUSES OF DEATH IN MAJOR EARTHQUAKE EVENTS AROUND THE WORLD. THIS PAPER INVESTIGATES A RECENTLY DEVELOPED RETROFITTING TECHNOLOGY SPECIFICALLY AIMED AT PREVENTING OR PROLONGING THE COLLAPSE OF ADOBE (MUD BRICK) BUILDINGS UNDER STRONG EARTHQUAKES.
THIS TECHNOLOGY USES COMMON POLYPROPYLENE PACKAGING STRAPS TO FORM A MESH, WHICH IS THEN USED TO PREVENT BRITTLE MASONRY COLLAPSE. THE RETROFITTING TECHNIQUE IS TESTED USING STATIC, DIAGONAL LOADING OF MODEL WALL PANELS. IT IS SHOWN THAT THE PROPOSED TECHNIQUE EFFECTIVELY PREVENTS BRITTLE COLLAPSE OF THE PANEL AND THE LOSS OF DEBRIS. PARTIAL MESHES OF VARIOUS ORIENTATIONS ARE ALSO INVESTIGATED IN ORDER TO BETTER IDENTIFY THE ACTION OF THE MESH. FINALLY, AN IMPLEMENTATION PROJECT IS PRESENTED, INVOLVING A TRAINING PROGRAMME FOR RURAL MASONS IN NEPAL AND A PUBLIC SHAKE-TABLE DEMONSTRATION.
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PEFORMANCE OF EXISTING REINFORCED CONCRETE COLUMNS UNDER BIDIRECTIONAL SHEAR AND AXIAL LOADING
Author: Laura M. Flores | Size: 1.07 MB | Format:PDF | Quality:Unspecified | Publisher: University of California, San Diego REU Institution: University of California, Berkeley REU Advisor: Professor Jack P. Moehle | pages: 42
Many existing reinforced concrete structures were designed before the introduction of modern seismic code and are thus vulnerable to collapse in the event of an earthquake. It is often more economically feasible to retrofit these structural components than to completely replace them. In order to strengthen these susceptible reinforced concrete structures against seismic loading, it is important to understand the progression of damage and mechanisms causing collapse in such structures under both gravity and seismic loads. Large-scale shake table testing and verification studies are currently being conducted at UC Berkeley-PEER to aid in the development of an OpenSees analytical model which will simulate and predict the hysteretic response of existing reinforced concrete structures in future verification studies.
The purpose of this study was to produce column hysteretic data used to calibrate the OpenSees analytical model. Empirical capacity models were used to predict the hysteretic response of shear-critical reinforced concrete columns under gravity and seismic loading; in particular, shear failure and axial load collapse of these columns were closely examined. Based on pre-seismic ACI code, a column cross sectional analysis was completed to determine the undamaged capacity of the column. A one-third scale model of the column was fabricated and an experimental setup allowing bi-directional loading (for simulation of seismic and gravity loads) was designed and constructed. Column specimens were then subjected to quasi-static testing and the measured column hysteretic response was compared to that predicted by empirical capacity models which form the basis of the OpenSees analytical model.
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Nonlinear seismic vulnerability evaluation of irregular steel buildings with cumulative damage indices
Author: Mohsen Gerami, Yahya Sharbati* and Abbas Sivandi-Pour | Size: 2.06 MB | Format:PDF | Quality:Unspecified | Publisher: Gerami et al. International Journal of Advanced Structural Engineering | Year: 2013 | pages: 15
Measuring structural damage during earthquakes has always been a challenging problem for earthquake engineers. Various damage indices are proposed with the objective of quantifying the structural damage in prototype and model structures subjected to seismic excitation. In this study, seismic vulnerability of irregular steel buildings is assessed in three dimensions considering effects of the panel zone, which has not been considered in recent studies of the field of seismic vulnerability. The buildings are modeled with different storeys and irregular plans.
Seismic performance of buildings was assessed in life-safety and collapse-prevention levels. Cumulative functions of damage indices are applied in the nonlinear dynamic analysis of buildings in the near-field ground motions. It is concluded that participation rates of deformation and energy in the damage of irregular buildings are 74.5% and 25.5%, respectively. Severe damage and collapse due to seismic dissipated energy occurred in the initial storeys of low-rise buildings and in the middle storeys of high-rise buildings.
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Posted by: freequo - 08-27-2013, 08:17 AM - Forum: Archive
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Article/eBook Full Name: Programming the Finite Element Method in Java and Android
Author(s): Bryan J. Macdonald
Edition: 1st
Publish Date: 2013
ISBN: 1908689188
Published By: Glasnevin Publishing
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SEISMIC ANALYSIS OF KNEE ELEMENTS FOR STEEL FRAMES
Author: DENIS EMIL CLEMENT | Size: 13.8 MB | Format:PDF | Quality:Unspecified | Publisher: UNIVERSITY OF OXFORD | Year: 2002 | pages: 243
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Nonlinear Static Pushover Analysis of a Shear Wall Building in Madinah
Author: M. Ajmal¥ ,M.K. Rahman¥ and M.H. Baluch¥ ¥ King Fahd University of Petroleum & Minerals Dhahran Saudi Arabia | Size: 1 MB | Format:PDF | Quality:Unspecified | Year: 2012 | pages: 37
1. Some large cities in the Eastern and Western Part of Saudi
Arabia are located close to fault zones. As the population
increases and new areas are developed, the seismic risk to
human life and infrastructure increases.
2. Most old structures aredesigned without considering
seismic effect. i.e. designed for gravity loads.
3. Recent seismic activity in Saudi Arabia have led to concern
about the safety of the existing reinforced concrete
buildings.
4. This research is planned as a joint collaboration between
King Fahd university of Petroleum and Minerals (KFUPM),
Saudi Arabia and Istanbul Technical University (ITU),
Turkey.
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Does anybody have this ebook ?, if you can upload it's will be very helpful.
Thank you very much
Article/eBook Full Name: Philosophy of Structures
Author(s): Eduardo Torroja
Edition: 1
Publish Date: 1967
ISBN: ASIN: B0007FMC4A
Published By: University of California Press
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Applicability of Nonlinear Multiple-Degree-of-Freedom Modeling for Design
Size: 5.9 MB | Format:PDF | Quality:Unspecified | Publisher: NEHRP Consultants Joint Venture A Partnership of the Applied Technology Council and the Consortium of Universities for Research in Earthquake Engineering | Year: 2010 | pages: 222
Prevailing practice for performance-based seismic design is based largely on products that have been developed under the direction of National Earthquake Hazards Reduction Program (NEHRP) agencies and other key contributors. Many of
these documents recognize and allow several different performance-based analytical methods, but much of their focus is on nonlinear static analysis procedures.
The Federal Emergency Management Agency (FEMA) report, FEMA 440 Improvement of Nonlinear Static Seismic Analysis Procedures (FEMA, 2005), was
commissioned by FEMA to evaluate and develop improvements to nonlinear static
analysis procedures. In FEMA 440, differences between nonlinear static and
nonlinear response history analysis results were attributed to a number of factors
including: (1) inaccuracies in the “equal displacement approximation” in the short
period range; (2) dynamic P-Delta effects and instability; (3) static load vector assumptions; (4) strength and stiffness degradation; (5) multiple-degree-of-freedom effects; and (6) soil-structure interaction effects. Recommendations contained within FEMA 440 resulted in immediate improvement in nonlinear static analysis procedures and were incorporated in the development of the American Society of Civil Engineers (ASCE) standard ASCE/SEI 41-06, Seismic
Rehabilitation of Existing Buildings (ASCE, 2007). The FEMA 440 report, however, also identified certain technical issues needing additional study. These included: (1)
expansion of component and global modeling to include nonlinear degradation of strength and stiffness; (2) improvement of simplified nonlinear modeling to include multiple-degree-of-freedom effects; and (3) improvement of modeling to include soil-foundation-structure interaction effects.
FEMA has since supported further developmental work on the first of these issues, nonlinear degradation of strength and stiffness. The results of this work are
contained in the FEMA P-440A report, Effects of Strength and Stiffness Degradation on Seismic Response (FEMA, 2009a).
Regarding the second of these issues, FEMA 440 concluded that current nonlinear static analysis procedures, which are based on single-degree-of-freedom (SDOF) models, are limited in their ability to capture the complex behavior of structures that experience multiple-degree-of-freedom (MDOF) response, and that improved nonlinear analysis techniques to more reliably address MDOF effects were needed.
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