Skip header and navigation

38 records – page 2 of 4.

Direct Displacement Design of Tall CLT Building with Deformable Diaphragms

https://research.thinkwood.com/en/permalink/catalogue1650
Year of Publication
2016
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Bolvardi, Vahab
Pei, Shiling
van de Lindt, John
Dolan, James
Year of Publication
2016
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Design and Systems
Seismic
Keywords
Inter-Story Isolation
Displacement-Based Design
Simulation
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3506-3514
Summary
In order to cope with the speed of urbanization around the world especially in areas of high seismicity, researchers and engineers have always been investigating cost-effective building systems with high seismic performance. Cross Laminated Timber (CLT) is a wood based material that is suitable for tall building construction. However, the current CLT system is prone to connection damage in strong earthquakes due to the vast majority of the system ductility resides in connections. One solution is the concept of inter-story isolation to develop a potentially resilient system that can remain damage free during strong earthquakes. A generalized displacement-based design method was developed to design an inter-story isolation system for a tall wood building based on articulated damage expectations. A12-story CLT building with one isolation layer was used to illustrate the proposed design method. The building performance was validated through numerical simulation under different seismic hazard levels.
Online Access
Free
Resource Link
Less detail

Ductility Based Force Reduction Factors for Symmetrical Cross-Laminated Timber Structures

https://research.thinkwood.com/en/permalink/catalogue446
Year of Publication
2014
Topic
Mechanical Properties
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Walls
Author
Popovski, Marjan
Pei, Shiling
van de Lindt, John
Karacabeyli, Erol
Organization
European Association of Earthquake Engineering
Year of Publication
2014
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Walls
Topic
Mechanical Properties
Seismic
Keywords
Force Modification Factors
Ductility
National Building Code of Canada
Fasteners
Seismic Performance
Conference
Second European Conference on Earthquake Engineering and Seismology
Research Status
Complete
Notes
August 25-29, 2014, Istanbul, Turkey
Summary
Cross-laminated timber (CLT) as a structural system has not been fully introduced in European or North American building codes. One of the most important issues for designers of CLT structures in earthquake prone regions when equivalent static design procedure is used, are the values for the force modification factors (R-factors) for this structural system. Consequently, the objective of this study was to derive suitable ductility-based force modification factors (Rd-factors) for seismic design of CLT buildings for the National Building Code of Canada (NBCC). For that purpose, the six-storey NEESWood Capstone wood-frame building was redesigned as a CLT structure and was used as a reference symmetrical structure for the analyses. The same floor plan was used to develop models for ten and fifteen storey buildings. Non-linear analytical models of the buildings designed with different Rd-factors were developed using the SAPWood computer program. CLT walls were modelled using the output from mechanics models developed in Matlab that were verified against CLT wall tests conducted at FPInnovations. Two design methodologies for determining the CLT wall design resistance (to include and exclude the influence of the hold-downs), were used. To study the effects of fastener behaviour on the R-factors, three different fasteners (16d nails, 4x70mm and 5x90mm screws) used to connect the CLT walls, were used in the analyses. Each of the 3-D building models was subjected to a series of 22 bi-axial input earthquake motions suggested in the FEMA P-695 procedure. Based on the results, the fragility curves were developed for the analysed buildings. Results showed that an Rd-factor of 2.0 is appropriate conservative estimate for the symmetrical CLT buildings studied, for the chosen level of seismic performance.
Online Access
Free
Resource Link
Less detail

Energy Consumption Analysis of Multistory Cross-Laminated Timber Residential Buildings: A Comparative Study

https://research.thinkwood.com/en/permalink/catalogue695
Year of Publication
2016
Topic
Energy Performance
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Khavari, Ali
Pei, Shiling
Tabares-Velasco, Paulo
Publisher
American Society of Civil Engineers
Year of Publication
2016
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Energy Performance
Keywords
Energy Consumption
Energy Efficiency
Residential
Sensitivity Analysis
Research Status
Complete
Series
Journal of Architectural Engineering
Summary
Cross-laminated timber (CLT) is a new panelized mass timber product that is suitable for building tall wood buildings (higher than eight stories) because of its structural robustness and superior fire resistance as compared with traditional light-framed wood systems. A number of tall CLT buildings have been constructed around the world in the past decade, and taller projects are being planned. The energy efficiency of this emerging building type was evaluated numerically in this comparative study with the use of a building energy simulation program. A 10-story multiunit residential building model constructed using CLT was simulated and compared with a light-frame metal construction model with the same floor plan. A sensitivity analysis was also conducted to study the impact of different weather profiles, building types, and internal load conditions on building energy consumption performance. It was concluded that CLT generally provides significant improvement on heating energy efficiency as a heavy and air-tight envelope, but its energy performance efficiency can be affected by weather, building size, internal loading, and HVAC control.
Online Access
Free
Resource Link
Less detail

Equivalent lateral force procedure for a building with a self-centering rocking story of cross-laminated timber (CLT) walls

https://research.thinkwood.com/en/permalink/catalogue3223
Year of Publication
2021
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
Ricco, Marco Lo
Rammer, Douglas
Amini, M. Omar
Ghorbanpoor, Al
Pei, Shiling
Zimmerman, Reid B.
Organization
Forest Products Laboratory
Year of Publication
2021
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Seismic
Keywords
Equivalent Lateral Force Procedure
Seismic Isolation
Rocking Story
Pendulum
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
The Equivalent Lateral Force (ELF) procedure is the most widely used seismic analysis approach, because of its simplicity and practicality in preliminary and final design phases. This paper applies the ELF procedure to a hypothetical building that stands 5 stories tall, with a 4-story superstructure supported on a rocking story of elliptically profiled cross-laminated timber (CLT) walls. First-generation prototypes made from six CLT panels of 5-ply, 175 mm, thickness—each measuring 2.44 m by 3.66 m in respective width and height—demonstrated that elliptical geometry controls lateral stiffness, inherent damping, and self-centering of the walls. Full-scale, cyclic, quasi-static, lateral-load-displacement tests—under simulated gravity loads ranging from 133 to 400 kN—established effective stiffness and damping inputs for the ELF procedure. The prototypes produced two modes of elliptical pendulum response by changing steel connections to the floor and ceiling beams. The first connection guides panels through rolling, and the second connection forces panels into slip-friction for enhanced damping but reduced durability of CLT. Because the base rocking story of elliptically profiled CLT walls behaves like an inverted pendulum system, the ELF procedure references existing design provisions for seismically isolated structures.
Online Access
Free
Resource Link
Less detail

Executive Report: Full-Scale Shake Table Testing of a Two-Story Mass Timber Building with Resilient Rocking Wall Lateral System

https://research.thinkwood.com/en/permalink/catalogue1151
Year of Publication
2017
Topic
Seismic
Design and Systems
Material
CLT (Cross-Laminated Timber)
Timber-Concrete Composite
Application
Wood Building Systems
Author
Pei, Shiling
Year of Publication
2017
Format
Report
Material
CLT (Cross-Laminated Timber)
Timber-Concrete Composite
Application
Wood Building Systems
Topic
Seismic
Design and Systems
Keywords
Full Scale
Shake Table Test
Rocking Walls
Research Status
Complete
Summary
This report is prepared for Softwood Lumber Board (SLB) by the NHERI TallWood Project team in order to provide a brief and timely update on the progress and preliminary research findings from the NHERI TallWood Project. This report is focused on the full-scale shake table test of a two-story mass timber building conducted during the summer of 2017 at NHERI@UC San Diego outdoor shake table. The shake table test described in this report was conducted during a three-month period from June to August 2017. As the research team is still working on processing and analyzing the data obtained from the experiments, this report only discusses preliminary findings in a qualitative manner. The research team is expected to produce additional reports and publications based on the test results in the near future.
Online Access
Free
Resource Link
Less detail

Experimental Investigation of Self-Centering Cross Laminated Timber Walls

https://research.thinkwood.com/en/permalink/catalogue1654
Year of Publication
2016
Topic
Seismic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Ganey, Ryan
Berman, Jeffrey
Yao, Lihong
Dolan, Daniel
Akbas, Tugce
Loftus, Sara
Sause, Richard
Ricles, James
Pei, Shiling
van de Lindt, John
Blomgren, Hans-Erik
Year of Publication
2016
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Seismic
Mechanical Properties
Keywords
Lateral Load Resisting System
Post-Tensioning
U-Shaped Flexural Plates
Limit States
Self-Centering
Strength
Stiffness
Interstory Drifts
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3547-3554
Summary
This paper describes experiments conducted to develop a resilient lateral force resisting wall system that combines cross-laminated timber (CLT) panels with vertical post-tensioning (PT) to provide post-event re-centering. Supplemental mild steel U-shaped flexural plate devices (UFPs) are intended to yield under cyclic loading while the PT and CLT components remain undamaged until large inter-story drifts are experienced by the wall. The experiments were designed to explore various limit states for self-centering CLT (SC-CLT) walls, including their dependence on design variables and their impact on performance, and to investigate strength and stiffness degradation at large interstory drifts. It was found that the SC-CLT walls were able to re-center even after large drift cycles and the crushing of the CLT material was the governing limit sate for most specimens. A hierarchy of desirable limit states was identified consisting of UFP yielding, CLT splitting, PT yielding, and CLT crushing.
Online Access
Free
Resource Link
Less detail

Experimental seismic behavior of a two-story CLT platform building

https://research.thinkwood.com/en/permalink/catalogue3227
Year of Publication
2019
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
Lindt, John W. van de
Furley, Jace
Amini, M. Omar
Pei, Shiling
Tamagnone, Gabriele
Barbosa, Andre R.
Rammer, Doug
Line, Philip
Fragiacomo, Massimo
Popovski, Marjan
Organization
Forest Products Laboratory
Publisher
Elsevier
Year of Publication
2019
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Seismic
Keywords
Shake Table Test
Earthquake
Research Status
Complete
Series
Engineering Structures
Summary
Cross-laminated timber (CLT) manufacturing and construction has been steadily growing since its inception in Europe in the 1990s. In the US, the growth of the CLT adoption is inhibited by the lack of codified design provisions for CLT in high seismic regions. This led to a multi-year study conducted by Colorado State University to investigate suitable seismic design parameters of CLT shear wall systems. This paper presents the results from a series of shake-table tests featuring a full-scale two-story mass-timber building utilizing CLT Seismic Force Resisting Systems (SFRS). The building was designed using an R- factor equal to 4.0 under the equivalent lateral force procedure specifications of the ASCE 7-16 Standard. The test program included three phases with different wall configurations, reflecting different wall panel aspect ratios and the existence of transverse CLT walls. Test results indicate that the code-level life safety objective was achieved in all test configurations. The addition of transverse walls did not affect the ability of the panels to rock, and improved the performance of the building structural system.
Online Access
Free
Resource Link
Less detail

Experimental Seismic Behavior of a Two-Story CLT Platform Building: Shake Table Testing Results

https://research.thinkwood.com/en/permalink/catalogue2052
Year of Publication
2018
Topic
Seismic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
van de Lindt, John
Amini, Omar
Furley, Jace
Pei, Shiling
Tamagnone, Gabriele
Barbosa, André
Line, Philip
Rammer, Douglas
Fragiacomo, Massimo
Organization
Colorado State University
University of Trieste
Oregon State University
Amarican Wood Council
Forest Products Laboratory
University of L'Aquila
Year of Publication
2018
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Seismic
Mechanical Properties
Keywords
Shake Table Tests
Full Scale
Service Level Earthquake
Design Base Earthquake
Maximum Considered Earthquake
Seismic Force Resisting System
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
With the increased usage of Cross Laminated Timber (CLT) in the United States, research efforts have been focused on demonstrating CLT as an effective Seismic Force Resisting System (SFRS). Presented in this paper are the findings of full-scale shake table tests of a two-story 223 m2 (2400 ft2) building with two sets of CLT shear walls on the first and second story. The testing consisted of three phases, each with a unique wall configuration, but only the first phase is presented herein, which consisted of a shear wall with 4:1 aspect ratio CLT panels. The structure was subjected to ground motions scaled to intensities that correspond to a Service Level Earthquake (SLE), Design Base Earthquake (DBE), and Maximum Considered Earthquake (MCE) respectively. In all phases and motions the structure performed well and was in accordance with FEMA collapse prevention requirements for each motion intensity.
Online Access
Free
Resource Link
Less detail

Experimental seismic behaviour of a two-story CLT platform building: design and shake table testing

https://research.thinkwood.com/en/permalink/catalogue3231
Year of Publication
2018
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Author
Lindt, John W. van de
Furley, Jace
Amini, M. Omar
Pei, Shiling
Tamagnone, Gabriele
Barbosa, Andre
Rammer, Doug
Line, Philip
Fragiacomo, Massimo
Popovski, Marjan
Organization
Forest Products Laboratory
Year of Publication
2018
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Seismic
Keywords
Seismic Force Resisting System
FEMA P-695 Methodology
Shake Table Testing
Conference
16th European Conference on Earthquake Engineering
Research Status
Complete
Summary
Since its introduction in Europe more than two decades ago, Cross Laminated Timber (CLT) is viewed as a new-generation of engineered wood products and has found its way into the US construction market. Recent research efforts have demonstrated that CLT can be effectively utilized as a seismic force resisting system. This paper presents the results of part of a study conducted at Colorado State University to systematically investigate seismic behaviour of CLT shear wall systems in regions of high seismicity for use in the United States. Specifically, the results of a full-scale shake table test of a two-storey 223 m2 building. The CLT special shear walls in the building were designed based on a design methodology that resulted from connector and reverse cyclic testing of isolated CLT shear walls using a generic connector. The main design assumption for these walls is that all overturning was resisted by the overturning anchor (tie-down rod or hold-downs) at the wall ends and the shear is resisted by the generic angle brackets connected with nails. The shake table tests were performed in three phases with each phase consisting of a different CLT wall configuration. Phase 1 and 2 were multi-panel configurations with 4:1 (h/b) and 2:1 aspect ratio panels, respectively. Phase 3 was another 4:1 aspect ratio wall with return walls added in the transverse direction to examine their effect on the overall response. The structure was subjected to several ground motions including one scaled to the maximum credible earthquake (MCE), equivalent to a 2475 year return period.
Online Access
Free
Resource Link
Less detail

Force Modification Factors for Cross Laminated Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue363
Year of Publication
2012
Topic
Seismic
Market and Adoption
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Pei, Shiling
Popovski, Marjan
van de Lindt, John
Organization
FPInnovations
Year of Publication
2012
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Seismic
Market and Adoption
Keywords
Performance-Based Seismic Design
Canada
US
Force Modification Factors
Mid-Rise
Research Status
Complete
Summary
European experience shows that Cross-Laminated Timber (CLT) can be competitive in mid-rise and high-rise buildings. Although this system has not been used to the same extent so far in North America, it can be viable wood structural solution for the shift towards sustainable densification of urban and suburban centers. For these reasons FPInnovations has undertaken a multi-disciplinary project on determining the performance of a typical CLT construction, including quantifying the seismic resistance and force modification factors for CLT buildings in Canada and the US. In this report, a performance-based seismic design (PBSD) of a CLT building was conducted and the seismic response of the CLT building was compared to that of a wood-frame structure tested during the NEESWood project. A suitable force modification factors (R-factors) for CLT mid-rise buildings with different fasteners were recommended for seismic design in Canada and the US. The six-storey NEESWood Capstone building was redesigned as a CLT building using the PBSD procedure developed during the NEESWood project. The results from the quasi-static tests on CLT walls performed at FPInnovations were used as input information for modeling of the main load resisting elements of the structure, the CLT walls. Once the satisfactory design of the CLT mid-rise structure was established through PBSD, a force-based design was developed with varying R-factors and that design was compared to the PBSD result. In this way, suitable R-factors were calibrated so that they can yield equivalent seismic performance of the CLT building when designed using the traditional force-based design methods. Based on the results of this study it is recommended that a value of Rd=2.5 and Ro=1.5 can be assigned for structures with symmetrical floor plans according to NBCC. In the US an R=4.5 can be used for symmetrical CLT structures designed according to ASCE7. These values can be assigned provided that the design values for CLT walls considered (and implemented in the material design standards) are similar to the values determined in this study using the kinematics model developed that includes the influence of the hold-downs in the CLT wall resistance. Design of the CLT building with those R-factors using the equivalent static procedures in the US and Canada will result in the CLT building having similar seismic performance to that of the tested wood-frame NEESWood building, which had only minor non-structural damage during a rare earthquake event.
Online Access
Free
Resource Link
Less detail

38 records – page 2 of 4.