Comparison between Contemporary Architectural Form in Cities with High versus Low Seismicity

2009 ◽  
Vol 25 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Andrew Charleson
Keyword(s):  
Seismic Design ◽  
Shear Walls ◽  
Lateral Force ◽  
Unexpected Result ◽  
Structural Elements ◽  
Structural Walls ◽  
Design Constraints ◽  
Architectural Form ◽  
System A ◽  
High Seismicity

This study investigates whether seismic design constraints reduce the architectural interest of buildings in areas subject to high rather than low seismicity. Sixty-three of the most architecturally interesting low-rise buildings from 20 cities, half of which are located in high-seismicity zones, were assessed aesthetically and analyzed structurally. On average, each group of buildings was found to possess the same level of architectural interest and degree of configuration irregularity. Reinforced concrete shear walls were found to be the predominant lateral force resisting system. A concentration of building types in the low-seismicity set of buildings that used structural walls for physical security and other purposes led to the unexpected result of those buildings possessing significantly greater structural footprints than buildings from high-seismicity areas. This finding serves as a reminder that structural elements play far more roles in architecture than merely resisting lateral forces.

Lateral Force Resisting Systems Made of Cold-Formed Steel Material: Proposal of Seismic Design Criteria for 2nd Generation of Eurocode 8

2021 ◽  
Vol 885 ◽  
pp. 127-132
Author(s):  
Sarmad Shakeel ◽  
Alessia Campiche
Keyword(s):  
Seismic Design ◽  
Shear Walls ◽  
Lateral Force ◽  
Background Information ◽  
Design Criteria ◽  
Eurocode 8 ◽  
Building Structures ◽  
Design Standards ◽  
Design Strength ◽  
Cold Formed Steel

The current edition of Eurocode 8 does not cover the design of the Cold-Formed steel (CFS) building structures under the seismic design condition. As part of the revision process of Euro-code 8 to reflect the outcomes of extensive research carried out in the past decade, University of Naples “Federico II” is involved in the validation of existing seismic design criteria and development of new rules for the design of CFS systems. In particular, different types of Lateral Force Resisting System (LFRS) are analyzed that can be listed in the second generation of Eurocode 8. The investigated LFRS’s include CFS strap braced walls and CFS shear walls with steel sheets, wood, or gypsum sheathing. This paper provides the background information on the research works and the reference design standards, already being used in some parts of the world, which formed the basis of design criteria for these LFRS systems. The design criteria for the LFRS-s common to CFS buildings would include rules necessary for ensuring the dissipative behavior, appropriate values of the behavior factor, guidelines to predict the design strength, geometrical and mechanical limitations.

Seismic response of structural walls: recent developments

2001 ◽  
Vol 28 (6) ◽  
pp. 922-937 ◽  
Author(s):  
T Paulay
Keyword(s):  
Reinforced Concrete ◽  
Seismic Response ◽  
Seismic Design ◽  
Limit State ◽  
Lateral Force ◽  
Structural Walls ◽  
Structural Class ◽  
Response Component ◽  
Displacement Ductility ◽  
Ductility Capacity

It is postulated that for purposes of seismic design, the ductile behaviour of lateral force-resisting wall components, elements, and indeed the entire system can be satisfactorily simulated by bilinear force–displacement modeling. This enables displacement relationships between the system and its constituent components at a particular limit state to be readily established. To this end, some widely used fallacies, relevant to the transition from the elastic to the plastic domain of behaviour, are exposed. A redefinition of stiffness and yield displacement allows more realistic predictions of the important feature of seismic response, component displacements, to be made. The concepts are rational, yet very simple. Their applications are interwoven with the designer's intentions. Contrary to current design practice, whereby a specific global displacement ductility capacity is prescribed for a particular structural class, the designer can determine the acceptable displacement demand to be imposed on the system. This should protect critical components against excessive displacements. Specific intended displacement demands and capacities of systems comprising reinforced concrete cantilever and coupled walls can be estimated.Key words: ductility, displacements, reinforced concrete, seismic design, stiffness, structural walls.

Below-Grade Expansion Joints: Challenges and Best Practices

2019 ◽  
Author(s):  
Marisa L. Turner ◽  
Rose F. McClure
Keyword(s):  
Best Practices ◽  
Best Practice ◽  
Shear Walls ◽  
Groundwater Table ◽  
Structural Elements ◽  
Structural Walls ◽  
Expansion Joints ◽  
Design Considerations ◽  
New Buildings ◽  
Structural Separation

<p>Many of our cities are running out of usable construction space for large buildings. New buildings are reaching new heights and new depths, often extending several stories below-grade. This presents challenges for waterproofing, particularly when building foundations extend below the groundwater table. With climate change and sea-level rise, many geographic areas will increasingly need to consider groundwater.</p><p>Building code requirements, especially in seismic regions, often require engineers to design movement joints or separation joints in below-grade structures. But foundation waterproofing materials are designed to seal around a building, not a void or an excavation. Structural joints are more susceptible to leakage, and higher volumes of leakage, than areas with solid backup.</p><p>We review design considerations for movement joints and present two case studies: a parking structure with structural separation joints between exterior shotcrete shear walls; and a hospital campus relying on below- grade expansion joints between buildings with differing foundation systems. In both, the presence of below- grade joints necessitates more complicated detailing and installation.</p><p>Experience shows us the best practice is to waterproof the building, not the void. Performance is best when the below-grade structural walls provide a solid, continuous substrate. Where movement joints cannot be avoided, we recommend designing structural elements to also meet the needs of the waterproofing system.</p>

scholarly journals Influence of shear flexibility in structural shear walls on pushover analysis

Mechanika ◽  
2020 ◽  
Vol 26 (2) ◽  
pp. 146-152
Author(s):  
Mário Rui Tiago Arruda ◽  
Bruno Lopes ◽  
Mário Ferreira ◽  
Tadas Zingaila
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Seismic Design ◽  
Pushover Analysis ◽  
Concrete Structures ◽  
Shear Walls ◽  
Reinforced Concrete Structures ◽  
Structural Walls ◽  
Shell Elements ◽  
N2 Method

The aim of this work is to show the main differences which exist, taking in to account the influence of the type of finite element used, when performing pushover analysis of reinforced concrete structures. The non-linear analysis was performed using FE software SAP2000, and the results were extracted from models including Frame and Shell elements, respectively. Several reinforced concrete structures were modelled with Frame elements and Shell elements, which will be further presented. Therefore, it was possible to validate the results obtained from the analysis, also to identify certain restrictions according to the type of finite element used in the modelling of the resistant walls. In the first phase, three isolated structural walls were modelled with distinct geometries. The first one presents a rectangular shape, the second – “L” shape and the third one “U” shape. The application of pushover analysis through the different examples presented in this document, intends to validate the results obtained for the Shell elements. Subsequently, the same kind of analysis was performed on a building. These examples intend to show that the performance of ductility is strongly dependent from the type of element, which is not taken into account in the pushover analysis nowadays. N2 method was applied to all examples, in order to understand the differences in the structures seismic design, according to the type of element used in the modelling. The results are compared, and the differences are identified. As well as, the limitations of applicability of Shell elements in the modelling of structural walls were determined.

Influence of the distribution of the shear walls on the seismic response of the buildings

2020 ◽  
Vol 15 (1) ◽  
pp. 37-44
Author(s):  
El Mehdi Echebba ◽  
Hasnae Boubel ◽  
Oumnia Elmrabet ◽  
Mohamed Rougui
Keyword(s):  
Structural Analysis ◽  
Seismic Response ◽  
Natural Frequency ◽  
Structural Design ◽  
Structural Response ◽  
Shear Walls ◽  
Structural Elements ◽  
Analysis Software ◽  
Ansys Apdl ◽  
The Impact

Abstract In this paper, an evaluation was tried for the impact of structural design on structural response. Several situations are foreseen as the possibilities of changing the distribution of the structural elements (sails, columns, etc.), the width of the structure and the number of floors indicates the adapted type of bracing for a given structure by referring only to its Geometric dimensions. This was done by studying the effect of the technical design of the building on the natural frequency of the structure with the study of the influence of the distribution of the structural elements on the seismic response of the building, taking into account of the requirements of the Moroccan earthquake regulations 2000/2011 and using the ANSYS APDL and Robot Structural Analysis software.

scholarly journals Lateral resistance of mass timber shear wall connected by withdrawal-type connectors

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Sung-Jun Pang ◽  
Kyung-Sun Ahn ◽  
Seog Goo Kang ◽  
Jung-Kwon Oh
Keyword(s):  
Experimental Data ◽  
Seismic Design ◽  
Shear Walls ◽  
Shear Wall ◽  
Vertical Load ◽  
Lateral Resistance ◽  
Kinematic Models ◽  
Mass Timber ◽  
Timber Shear Walls ◽  
Timber Shear Wall

AbstractIn this study, the lateral resistances of mass timber shear walls were investigated for seismic design. The lateral resistances were predicted by kinematic models with mechanical properties of connectors, and compared with experimental data. Four out of 7 shear wall specimens consisted of a single Ply-lam panel and withdrawal-type connectors. Three out of 7 shear wall specimens consisted of two panels made by dividing a single panel in half. The divided panels were connected by 2 or 4 connectors like a single panel before being divided. The applied vertical load was 0, 24, or 120 kN, and the number of connectors for connecting the Ply-lam wall-to-floor was 2 or 4. As a result, the tested data were 6.3 to 52.7% higher than the predicted value by kinematic models, and it means that the lateral resistance can be designed by the behavior of the connector, and the prediction will be safe. The effects of wall-to-wall connectors, wall-to-floor connectors and vertical loads on the shear wall were analyzed with the experimental data.

scholarly journals Reconciling Architectural Design with Seismic Codes

Prostor ◽  
2021 ◽  
Vol 29 (1 (61)) ◽  
pp. 42-55
Author(s):  
Cengiz Özmen
Keyword(s):  
Reinforced Concrete ◽  
Seismic Design ◽  
Cross Sections ◽  
Architectural Design ◽  
Residential Buildings ◽  
Shear Walls ◽  
Spatial Arrangement ◽  
Design Principles ◽  
Seismic Codes ◽  
Architectural Analysis

Seismic codes include strict requirements for the design and construction of mid-rise reinforced concrete residential buildings. These requirements call for the symmetric and regular arrangement of the structural system, increased cross-sections for columns, and the introduction of shear walls to counteract the effects of lateral seismic loads. It is challenging for architects to reconcile the demands of these codes with the spatial arrangement and commercial appeal of their designs. This study argues that such reconciliation is possible through an architectural analysis. First, the effectiveness of applying the seismic design principles required by the codes is demonstrated with the comparative analysis of two finite element models. Then three pairs of architectural models, representing the most common floor plan arrangements for such buildings in Turkey, are architecturally analyzed before and after the application of seismic design principles in terms of floor area and access to view. The results demonstrate that within the context defined by the methodology of this study, considerable seismic achievement can be achieved in mid-rise reinforced concrete residential buildings by the application of relatively few, basic design features by the architects.

scholarly journals Shear and Flexural Stiffnesses of Reinforced Concrete Shear Walls Subjected to Cyclic Loading

2014 ◽  
Vol 8 (1) ◽  
pp. 104-121 ◽  
Author(s):  
T. O. Tang ◽  
R. K.L. Su
Keyword(s):  
Seismic Analysis ◽  
Classical Mechanics ◽  
Shear Walls ◽  
Shear Stiffness ◽  
Eurocode 8 ◽  
Design Codes ◽  
Structural Walls ◽  
Load Distributions ◽  
Classical Models ◽  
Ductility Capacity

Seismic analyses of concrete structures under maximum-considered earthquakes require the use of reduced stiffness accounting for cracks and degraded materials. Structural walls, different to other flexural dominated components, are sensitive to both shear and flexural stiffness degradations. Adoption of the gross shear stiffness for walls in seismic analysis prevails particularly for the design codes in the US. Yet available experimental results indicate that this could overstate the shear stiffness by more than double, which would hamper the actual predictions of building periods and shear load distributions among columns and walls. In addition, the deformation capacity could be drastically understated if the stipulated constant ductility capacity is adopted. This paper reviews the available simplified shear and flexural models, which stem from classical mechanics, empirical formulations and/or parametric studies, suitable for structural walls at the state-of-the-art. Reviews on the recommended flexural and shear stiffnesses by prominent design codes such as ACI318-11, Eurocode 8 and CSA are included. A database comprised of walls subjected to reverse-cyclic loads is formed to evaluate the performance of each model. It is found that there exist classical models that could outweigh overconservative codified values with comparable simplicity for practical uses.

scholarly journals Characterisation of the Lateral Resistance of Stapled Shear Walls

2019 ◽  
pp. 446-453
Author(s):  
Roberto Aranda ◽  
Alexander Salenikovich ◽  
J. Daniel Dolan ◽  
Peter Dechent
Keyword(s):  
Steel Wire ◽  
Cost Savings ◽  
Shear Walls ◽  
Lateral Force ◽  
Production Quality ◽  
Production Quality Control ◽  
Design Information ◽  
Displacement Capacity ◽  
Wood Construction ◽  
The Cost

Shear walls are the major components of the lateral-force-resisting system (LFRS) in light-frame wood buildings. With the growing popularity of mid-rise prefabricated light-frame wood construction, engineers need basic design information on the shear walls to design and produce safe structures in case of high winds and earthquakes. The racking resistance of light-frame shear walls depends on many factors, including sheathing and hold-down devices and, most importantly, sheathing-to-framing fastenings. While the performance of nailed shear walls has been studied extensively, and design information is included in the design codes, there is little information on stapled shear walls, specifically in the US and Canada. The cost of staples is significantly less than that of equivalent nails; hence, the use of staples instead of nails would allow cost savings in mass production if they provide sufficient resistance and displacement capacity in the engineered shear walls. This paper presents the results of a pilot study which was focused on the comparison of the performance of nailed and stapled shear walls in laboratory tests under monotonic and cyclic loading in accordance with ASTM E564 and E2126, respectively. Several series of tests were performed on 2.4-m (8-ft) square shear walls with 11-mm (7/16-in) OSB sheathing with various hold-downs and various spacing of sheathing staples and nails on the perimeter of the sheathing panels (5-cm (2-in), 10-cm (4-in) and 15-cm (6-in)) and 19-mm and 10-mm edge distances. The staples were 16-gauge (50-mm (2-in) long with 11-mm (7/16-in) crown). The nails were 8d box steel wire nails (63-mm (2½-in) long with 2.87-mm (0.113-in) diameter). The test results revealed a similar performance of the nailed and stapled shear walls, and the need for careful detailing. Therefore, prefabrication of walls in the factory settings is preferable to the on-site construction to allow the production quality control.

Sign in / Sign up

Export Citation Format

Share Document