Cross-laminated timber (CLT) is proving to be a promising solution for wood to compete in building sectors where steel and concrete have traditionally predominated. Studies at FPInnovations found that bare CLT floor systems differ from traditional lightweight wood joisted floors with typical mass around 4 lb./ft2 (20 kg/m2) and fundamental natural frequency above 15 Hz, and heavy concrete slab floors with a mass above 40 lb./ft2 (200 kg/m2) and fundamental natural frequency below 8 Hz. Based on FPInnovations' test results, bare CLT floors were found to have mass varying from approximately 6 lb./ft2 (30 kg/m2) to 30 lb./ft2 (150 kg/m2), and a fundamental natural frequency above 9 Hz. Due to these special properties, the existing standard vibration controlled design methods for lightweight and heavy floors may not be applicable for CLT floors. ...
Properties of CLT panels are influenced by the properties of their layers and the layer properties are in turn influenced by the structural characteristics of the laminate material. In order to realize the mechanical property potential of CLT panels it i...
Wood-concrete composite slab floors provide a promising solution for achieving long spans and shallow wood-based floor systems for large and tall wood buildings. In comparison with conventional wood floor systems, such long span and heavy floors have a lower fundamental natural frequency...
This study focused on the vibrational behaviour of a 3-ply cross-laminated timber (CLT) plate supported on two sides with different support conditions. Three end support setups were studied; 1) top load over the two supported edges, 2) direct fastening t...
The design and application of cross laminated timber (CLT) is s trongly influenced by rolling shear properties of cross layers. Hence, predicting the mechanical behaviour of CLT requires accurate information about its rolling shear properties. In this st...
It has been shown that measurement of elastic constants of orthotropic wood-based panel products can be more efficiently measured by modal testing technique. Identification of vibration modes and corresponding natural frequencies is key to the application of modal testing technique. This process is generally tedious and requires a number of measurement locations for mode shape identification. In this study, a simplified method for frequency identification was developed which will facilitate the adoption of the vibration-based testing technique for laboratory and industrial application. In the method, the relationship between frequency order and mode order is first studied considering the boundary condition, elastic properties of the orthotropic panel. An algorithm is proposed to predict the frequency values and mode indices based on corresponding normalized sensitivity to elastic constants, initial estimates of orthotropic ratios and measured fundamental natural frequency. The output from the algorithm can be used for identification of sensitive natural frequencies from up to three frequency spectra. Then the algorithm is integrated with the elastic calculation algorithm to extract the elastic constants from the sensitive frequencies. The elastic constants of cross laminated timber panels were measured by the proposed method. The moduli of elasticity agree well with static testing results. The calculated in-plane shear modulus was found to be within the expected range.
Cross laminated timber (CLT) is leading the evolution of wood construction throughout the world. As a two-dimensional plate-like construction product, the in-plane elastic constants of CLT panels are the fundamental parameters for serviceability design. The elastic constants including moduli of elasticity (MOE) in major and minor...
