Author: Tanner Louis ReijmPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A Numerical Analysis of Seismic Performance of Cross-laminated Timber Shear Wall Assemblies with Enhanced Anchor Tiedown Systems
Author: Tanner Louis ReijmNumerical Study on the Seismic Performance of Hybrid Steel Moment Frames with CLT Balloon Shear Walls
Author: Mehdi KhajehpourPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A proposed hybrid lateral load resisting system combining a moderately ductile steel moment resisting frame (SMRF) with Cross-laminated Timber (CLT) balloon-framed shear walls is investigated on 8, 12 and 16-storey case-study buildings using equivalent static, linear dynamic (modal), nonlinear static (push-over) and nonlinear dynamic (time history) analyses. First, a SMRF is designed using ETABS, then the hybrid structures are analysed in OpenSees. By adding the CLT shear wall to steel moment frame, the period of structure decreased and its stiffness increased. The time history analyses result revealed that by adding the CLT shear wall the maximum drift decreased, while the maximum base shear in hybrid structure slightly increased. The hold down uplift forces under earthquake records are reported and compared to each other. Using push-over capacity-curves, a ductility reduction factor of 3.6, an over strength factor of 1.57 and a seismic response modification factor of 5.67 are derived.
Numerical Modeling and Seismic Performance of Post-tensioned Cross-laminated Timber Rocking Wall Systems
Author: Alex William WilsonPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Both the high- and reduced-order model compared well against experimental tests for both single and coupled PT CLT rocking walls. Both archetypes were able to meet predetermined performance objectives and code acceptance criteria, while the assessed responses of the low- and mid-rise archetype proved to be more sensitive to ground motion pulses and far-field motions, respectively. For all assessed intensity levels, both buildings showed that nonstructural repair could be performed at a cost cheaper than total replacement. The low- and mid-rise building exhibited better nonstructural economic performance in high and low intensity level events, respectively
Development of Seismic Performance Factors for Cross-laminated Timber Shear Walls
Author: John W. Van de LindtPublisher:
ISBN:
Category : Earthquake engineering
Languages : en
Pages : 2
Book Description
Since its initial introduction in Europe more than two decades ago, cross-laminated timber (CLT) has been established as a new-generation product (UNFAO 2016). Recent construction projects in both Canada and the United States (Pei et al. 2016) and research efforts in Europe, North America, and Japan on CLT-based lateral force resisting systems (Pei et al. 2014) have demonstrated that CLT can be a viable alternative to steel and concrete in mid-rise construction, particularly in seismic regions. However, CLT-based seismic force resisting systems are not included in current design codes and standards, meaning that any CLT seismic design can be conducted only through alternative methods. This approach is both costly and complicated, making CLT less competitive than other conventional structural systems such as light-frame wood and heavier materials such as steel and concrete. The purpose of this Forest Products Laboratory partnership with Colorado State University is to determine seismic performance factors for CLT, thereby enabling CLT to be used efficiently and competitively throughout the United States.
Displacement-based seismic design for multi-storey cross laminated timber buildings
Author: Hummel, JohannesPublisher: kassel university press GmbH
ISBN: 3737602883
Category :
Languages : en
Pages : 224
Book Description
Key Terms: cross laminated timber, displacement-based seismic design, time history analysis, multi-storey timber structures, hysteretic behaviour
Cross Laminated Timber Shear Wall Connections for Seismic Applications
Author: Michael FalkPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
This report gives a state-of-the-art summary of current cross-laminated timber (CLT) shear wall systems and connections for seismic applications. CLT panels are gaining popularity as a building material because of their biaxial strength and light weight. CLT panels can be used in building construction not only as floors, but also as shear walls. However, the behavior of CLT shear wall systems under seismic load has yet to be defined. CLT panels are nearly rigid under in-plane loading. While this can be beneficial, structural system qualities that are valuable in seismic loading such as ductility and energy dissipation are difficult to achieve by the panels themselves. Therefore, for the lateral force resisting system to perform as needed, ductility and energy dissipation must come from the connection systems. There is a distinction between a connection and a connection system. The performance of CLT shear walls depends on the behavior of many different connections. CLT shear walls can be categorized into conventional shear walls, and rocking walls. Conventional shear walls follow many of the practices established in light-frame wood shear walls with the use of hold-downs and brackets. Conventional shear walls typically have a base connection with (multi-panel walls) or without (single-panel walls) vertical joint(s). Selection of these two connections can have a noticeable effect on the shear wall behavior. Rocking shear walls allow panel rotation in order to redirect forces into structural fuses in the connection system. The structural fuses vary on the type of rocking wall. These include U-shaped flexural plates (UFPs), energy dissipators, slip-friction connections, and interpanel shear connections. Most of the systems covered in this report displayed favorable seismic performance. Case studies of full-scale buildings that were tested under seismic ground motions are presented. Studies indicated that CLT connections and shear walls have the capability to perform well under seismic loading.
Seismic Design and Testing of Rocking Cross Laminated Timber Walls
Author: Ryan S. GaneyPublisher:
ISBN:
Category :
Languages : en
Pages : 312
Book Description
Mass timber is an attractive alternative to nonrenewable materials such as concrete and steel. High rise timber buildings have not been built in high seismic areas due to lack of ductile lateral force resisting systems that can have large seismic force reduction factors. Seismically resilient, lateral systems for tall timber buildings can be created by combining cross laminated timber (CLT) panels with post-tensioned (PT) self-centering technology. The concept features a system of stacked CLT walls where particular stories are equipped to rock against the above and below floor diaphragms through PT connections and are supplemented with mild steel U-shaped flexural plate energy dissipation devices (UFPs). Experiments were conducted to better understand rocking CLT wall behavior and seismic performance. The testing program consisted of five single wall tests with varying PT areas, initial tensioning force, CLT panel composition, and rocking surface and one coupled wall test with UFPs as the coupling devices. The walls were tested with a quasi-static reverse-cyclic load protocol. The experimental results showed a ductile response and good energy dissipation qualities. To evaluate the feasibility and performance of the rocking CLT wall system, prototype designs were developed for 8 to 14 story buildings in Seattle using a performance-based seismic design procedure. Performance was assessed using numerical simulations performed in OpenSees for ground motions representing a range of seismic hazards. The results were used to validate the performance-based seismic design procedure for tall timber buildings with rocking CLT walls.
Determination of Seismic Performance Factors for Cross-laminated Timber Shear Walls Based on FEMA P695 Methodology
Author: An Introduction to Seismic Building Shear Walls
Author: J. Paul Guyer, P.E., R.A.Publisher: Guyer Partners
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 64
Book Description
Introductory technical guidance for civil and structural engineers interested in design of buildings to resist seismic forces. Here is what is discussed: 1. INTRODUCTION 2 DESIGN FORCES 3. WALL COMPONENTS 4. IN-PLANE EFFECTS 5. OUT-OF-PLANE EFFECTS 6. CAST-IN-PLACE CONCRETE SHEAR WALLS 7. MASONRY SHEAR WALLS 8. WOOD STUD SHEAR WALLS 9. STEEL STUD SHEAR WALLS.
Seismic Performance and Design of Steel Plate Shear Walls with Low Yield Point Steel Infill Plates
Author: Tadeh ZirakianPublisher:
ISBN:
Category :
Languages : en
Pages : 233
Book Description
Steel plate shear walls (SPSWs) have been frequently used as the primary or part of the primary lateral force-resisting system in design of low-, medium-, and high-rise buildings. Their application has been based on two different design philosophies as well as detailing strategies. Stiffened and/or stocky-web SPSWs with improved buckling stability and high seismic performance have been mostly used in Japan, which is one of the pioneering countries in design and application of these systems. Unstiffened and slender-web SPSWs with relatively lower buckling and energy dissipation capacities, on the other hand, have been deemed as a rather economical alternative and accordingly widely used in the United States and Canada. Development and use of low yield point (LYP) steel with considerably low yield stress and high elongation capacity provides the possibility to combine merits of these two distinctive design strategies, and consequently result in rather cost-effective and high-performing SPSW systems. Although some reported studies have demonstrated the advantages of LYP steel shear walls, various aspects of structural and seismic characteristics of these systems have not been investigated thoroughly. In particular, the linkage between structural specifications and seismic performance and pathway to performance-based design of these systems are largely undeveloped. Hence, systematic investigations are required to facilitate the seismic design and prevalent application of such promising lateral force-resisting and energy dissipating systems. Although some reported studies have demonstrated the advantages of LYP steel shear walls, various aspects of structural and seismic characteristics of these systems have not been investigated thoroughly. In particular, the linkage between structural specifications and seismic performance and pathway to performance-based design of these systems are largely undeveloped. Hence, systematic investigations are required to facilitate the seismic design and prevalent application of such promising lateral force-resisting and energy dissipating systems. The main objectives of this research are to evaluate the structural behavior and seismic performance of unstiffened LYP steel shear wall systems in a rather comprehensive manner. To achieve these objectives, element-level investigations on steel plates, component-level investigations on SPSW panels, and system-level investigations on multi-story steel frame-shear wall structures are performed in a hierarchical and systematic manner. Through detailed element- and component-level investigations, it is shown that employment of LYP steel infill plates in SPSW systems facilitates the design and effectively improves the buckling stability, serviceability, and energy absorption capacity of such lateral force-resisting systems. Some practical design tools and recommendations are also provided through analytical and numerical studies. In system-level investigations, the effectiveness of use of LYP steel material in design and retrofit construction is demonstrated through nonlinear time-history analysis as well as seismic response and performance assessment of multi-story structures subjected to earthquake ground motions representing various hazard levels. Ultimately, the fragility methodology is utilized by developing appropriate fragility functions for probabilistic seismic performance and vulnerability assessment of structures designed and retrofitted with conventional and LYP steel infill plates. The results of this study are indicative of relatively lower damage probability and superior seismic performance of LYP steel shear wall systems.