scholarly journals In-Plane Strength and Stiffness of Cross-Laminated Timber Shear Walls

Buildings ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 100 ◽  
Author(s):  
Md Shahnewaz ◽  
Shahria Alam ◽  
Thomas Tannert
Keyword(s):  
Energy Dissipation ◽  
Peak Load ◽  
Shear Walls ◽  
Experimental Tests ◽  
Shear Loading ◽  
Peak Displacement ◽  
Cross Laminated Timber ◽  
Type Construction ◽  
Strength And Stiffness ◽  
Single Shear

The research presented herein investigated the in-plane performance of cross-laminated timber (CLT) shear walls for platform-type buildings under lateral loading. Finite element models of CLT connections (i.e., brackets, hold-downs and self-tapping screws) were developed in OpenSees and calibrated against experimental tests to represent the connections’ hysteresis behaviour under cyclic tension and shear loading. The results were incorporated into models of CLT single and coupled shear walls. The results in terms of peak displacement, peak load and energy dissipation were in good agreement when compared to full-scale shear wall tests. Subsequently, a parametric study of 56 single and 40 coupled CLT shear walls was conducted with varying numbers and types of connectors (wall-to-floor and wall-to-wall) for evaluating their seismic performance. It was found that the strength, stiffness and energy dissipation of the single and coupled CLT shear walls increased with an increase in the number of connectors. Single shear walls with hold-downs and brackets performed better under seismic loading compared to walls with brackets only. Similarly, coupled shear walls with four hold-downs performed better compared to walls with two hold-downs. Finally, ductility of coupled shear walls was found to be 31% higher compared to that of single shear walls. The findings from this research are useful for engineers to efficiently design CLT shear walls in platform-type construction.

Comparative dynamic investigation of cross-laminated wooden panel systems: Shaking-table tests and analysis

2017 ◽  
Vol 21 (10) ◽  
pp. 1421-1436 ◽  
Author(s):  
Viktor Hristovski ◽  
Violeta Mircevska ◽  
Bruno Dujic ◽  
Mihail Garevski
Keyword(s):  
Energy Dissipation ◽  
Earthquake Engineering ◽  
Dynamic Properties ◽  
Seismic Energy ◽  
Experimental Tests ◽  
Shaking Table ◽  
Shaking Table Tests ◽  
Equivalent Viscous Damping ◽  
Cross Laminated Timber ◽  
Engineering Seismology

Cross-laminated timber has recently gained great popularity in earthquake-prone areas for construction of residential, administrative, and other types of buildings. At the Laboratory of the Institute of Earthquake Engineering and Engineering Seismology in Skopje, comparative full-scale shaking-table tests of cross-laminated timber panel systems have been carried out as a part of the full research program on the seismic behavior of these types of wooden systems, realized by Institute of Earthquake Engineering and Engineering Seismology, Skopje, and the Faculty of Civil and Geodetic Engineering (UL FCG), University of Ljubljana. Two different specimens built of cross-laminated timber panels have been tested: specimen containing a pair of single-unit principal wall elements (Specimen 1) and specimen containing a pair of two-unit principal wall elements (Specimen 2). In this article, the results from the shaking-table tests obtained for Specimen 2 and numerically verified by using appropriate finite element method–based computational model are discussed. Reference is also made to the comparative analysis of the test results obtained for both specimens. One of the most important aspects of the research has been the estimation of the seismic energy-dissipation ability of Specimen 1 and 2, via calculation of the equivalent viscous damping using the performed experimental tests. It is generally concluded that Specimen 2 exhibits a similar rocking behavior as Specimen 1, with similar energy-dissipation ability. Both specimens have manifested slightly different dynamic properties, mostly because Specimen 2 has been designed with one anchor more compared to Specimen 1. Forced vibration tests have been used for identification of the effective stiffness on the contacts for Specimen 2. This research is expected to be a contribution toward clarification of the behavior and practical design of cross-laminated timber panel systems subjected to earthquake loading.

scholarly journals Investigating the behavior of boundary elements in steel shear walls with different connections

2021 ◽  
Vol 30 (4) ◽  
Author(s):  
Bi Ying
Keyword(s):  
Energy Dissipation ◽  
Shear Walls ◽  
High Strength ◽  
Shear Wall ◽  
High Ductility ◽  
Steel Shear Wall ◽  
Different Types ◽  
Energy Dissipation Capacity ◽  
Strength And Stiffness ◽  
Free Beam

In the recent five decades, steel shear walls have been one of the most important systems in the construction and rehabilitation of many structures. The system has many advantages including high strength and stiffness, high ductility and excellent energy dissipation capacity. Steel shear walls are made and executed in different types. These include walls with and without stiffeners as well as composites. Recent research shows that they are a type of steel shear wall in which the infill plate is slightly away from the boundary members. In fact, there is no connection between the infill plate and one of boundary members. Therefore, in this study, the behavior of traditional one-story-one-span steel shear walls with 4 different lengths was investigated. For comparison, walls in which the sheet was attached only to a beam or column were examined. Obtained results from the study showed that the lateral bearing capacity of samples with free beam or free column is less than that of samples with full connection, on average 20%. Also, the strength of the samples with free column is slightly higher than the samples with free beam. In addition, boundary members, especially columns, are much less affected by forces in free-column specimens than in other specimens, and this could decreases economical costs.

scholarly journals Lateral Performance of Cross-laminated Timber Shear Walls: Analytical and Numerical Investigations

2019 ◽  
pp. 213-218
Author(s):  
Md Shahnewaz ◽  
Thomas Tannert ◽  
Marjan Popovski
Keyword(s):  
Parametric Study ◽  
Experimental Validation ◽  
Analytical Procedure ◽  
Shear Walls ◽  
Finite Element Models ◽  
Seismic Loads ◽  
Viable Option ◽  
Cross Laminated Timber ◽  
Type Construction ◽  
Timber Shear Walls

Cross-laminated timber (CLT) is becoming a viable option for mid-rise buildings in North America. CLT walls are very effective in resisting lateral forces resulting from wind and seismic loads, yet no standard provisions are available to estimate the resistance of CLT shear walls under lateral loading. The present research investigated CLT shear wall’s performance by evaluating the preferred kinematic rocking behaviour. An analytical procedure was proposed to estimate the resistance of CLT shear walls in a platform type construction. Finite element models of CLT shear with various brackets and hold-downs connections were developed. The models were validated against experimental results. Furthermore, a parametric study on CLT shear walls with the variation of type and number of connectors was conducted. The resistance estimated from parametric study and against analytical were compared. The proposed formulas can be useful tool for the design of CLT platform-type buildings, however, require further experimental validation.

Deflection of cross-laminated timber shear walls for platform-type construction

2020 ◽  
Vol 221 ◽  
pp. 111091
Author(s):  
Md Shahnewaz ◽  
Marjan Popovski ◽  
Thomas Tannert
Keyword(s):  
Shear Walls ◽  
Cross Laminated Timber ◽  
Type Construction ◽  
Timber Shear Walls

scholarly journals Failure Modes and Mechanical Properties of Bracket Anchor Connections for Cross-Laminated-Timber

2019 ◽  
Vol 275 ◽  
pp. 01011
Author(s):  
Yinlan Shen ◽  
Johannes Schneider ◽  
Siegfried F. Stiemer ◽  
Xueyong Ren
Keyword(s):  
Failure Modes ◽  
Load Capacity ◽  
Peak Load ◽  
Force Transmission ◽  
Test Configuration ◽  
Cross Laminated Timber ◽  
State Tests ◽  
Transmission Mechanisms ◽  
Load Peak ◽  
Strength And Stiffness

The paper presents some experimental data and phenomenon on bracket anchor connections for Cross-Laminated-Timber. The goal of this research is to provide a better understanding of the seismic performance of bracket connections subjected to seismic actions and how to choose and design bracket connections for Cross-Laminated-Timber structures. Test configuration and experimental setups are illustrated in details; cyclic displacement schedules of the connections in two directions are presented considering that CLT wall has horizontal sliding in the plane and uplift at the end in quasi-state tests. Different failure modes and force transmission mechanisms of different connections under the loading protocol were analysed. And important quantities for seismic design such as strength, and stiffness, equivalent yield load, peak load and ductility of the connections are evaluated and compared among different kinds of connections; an excellent connector is revealed in ductility and load capacity by test data analysis. In addition, some suggestions to choose and design bracket anchor connections are given.

scholarly journals Seismic Strengthening of RC Structures Using Wall-Type Kagome Damping System

Buildings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 41
Author(s):  
Moo-Won Hur ◽  
Yonghun Lee ◽  
Min-Jun Jeon ◽  
Sang-Hyun Lee
Keyword(s):  
Energy Dissipation ◽  
Yield Strength ◽  
Shear Loading ◽  
Seismic Retrofitting ◽  
Rc Frame ◽  
Metallic Wire ◽  
Cyclic Shear ◽  
Loading Tests ◽  
Energy Dissipation Capacity ◽  
Strength And Stiffness

In this study, the Kagome truss damper, a metallic wire structures, was introduced and its mechanical properties were investigated through theoretical analyses and experimental tests. The yield strength of the Kagome damper is dependent on the geometric shape and diameter of the metallic wire. The Kagome damper has higher resistance to plastic buckling as well as lower anisotropy. Cyclic shear loading tests were conducted to investigate the energy dissipation capacity and stiffness/strength degradation by repeated loadings. The hysteretic properties obtained from the tests suggest that a modification of the ideal truss model with a hinged connection could be used to predict the yield strength and stiffness of the damper. For seismic retrofitting of a low-rise RC moment frame system, a wall-type Kagome damping system (WKDS) was proposed. The effectiveness of the proposed system was verified by conducting cyclic loading tests using a RC frame with/without the WKDS (story drift ratio limit 1.0%). The test results indicated that both the strength and stiffness of the RC frame increased to the target level and that its energy dissipation capacity was significantly enhanced. Nonlinear static and dynamic analyses were carried out to validate that the existing building structure can be effectively retrofitted using the proposed WKDS.

scholarly journals Material parametrization of natural rubber based compound and characterization of crack propagation under consideration of dissipative effects

2021 ◽  
Author(s):  
Dan Pornhagen ◽  
Konrad Schneider ◽  
Markus Stommel
Keyword(s):  
Energy Dissipation ◽  
Crack Propagation ◽  
Natural Rubber ◽  
Experimental Tests ◽  
Material Behavior ◽  
Prony Series ◽  
Material Forces ◽  
Cracking Behavior ◽  
Dissipative Effects

AbstractMost concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.

A combined experimental and computational study of mechanical properties after balloon kyphoplasty

2021 ◽  
pp. 095441192110139
Author(s):  
Philip Purcell ◽  
Fiona McEvoy ◽  
Stephen Tiernan ◽  
Derek Sweeney ◽  
Seamus Morris
Keyword(s):  
Computational Models ◽  
Computational Study ◽  
Case Reports ◽  
Experimental Tests ◽  
Balloon Kyphoplasty ◽  
Fatigue Tests ◽  
Vertebral Compression Fractures ◽  
Baseline Case ◽  
Strength And Stiffness ◽  
Stiffness Loss

Vertebral compression fractures rank among the most frequent injuries to the musculoskeletal system, with more than 1 million fractures per annum worldwide. The past decade has seen a considerable increase in the utilisation of surgical procedures such as balloon kyphoplasty to treat these injuries. While many kyphoplasty studies have examined the risk of damage to adjacent vertebra after treatment, recent case reports have also emerged to indicate the potential for the treated vertebra itself to re-collapse after surgery. The following study presents a combined experimental and computational study of balloon kyphoplasty which aims to establish a methodology capable of evaluating these cases of vertebral re-collapse. Results from both the experimental tests and computational models showed significant increases in strength and stiffness after treatment, by factors ranging from 1.44 to 1.93, respectively. Fatigue tests on treated specimens showed a 37% drop in the rate of stiffness loss compared to the untreated baseline case. Further analysis of the computational models concluded that inhibited PMMA interdigitation at the interface during kyphoplasty could reverse improvements in strength and stiffness that could otherwise be gained by the treatment.

Sign in / Sign up

Export Citation Format

Share Document