ST108-1 Building Tomorrow’s Society Bâtir la Société de Demain Fredericton, Canada June 13 – June 16, 2018/ Juin 13 – Juin 16, 2018 DEVELOPMENT OF LIGHTWEIGHT OVERLAID LAMINATED BAMBOO LUMBER FOR STRUCTURAL APPLICATIONS Xin, Guan 1,2 , Meng, Gong 2,3 and Qirong, Wu 1 1 College of Materials Engineering, Fujian Agriculture and Forestry University, China 2 Wood Science and Technology Centre, University of New Brunswick, Canada 3 [email protected] Abstract: The overlaid laminated bamboo lumber (OLBL) was developed for structural applications with an aim to substitute commonly-used building materials such as steel and concrete. The OLBL was, via a hot press, fabricated by cross-laminating bamboo layers, bamboo mats and phenolic impregnated adhesive papers. Since the weight of OLBL was governed by the high density bamboo layer, the panels made of OLBL had a relatively high density value of about 850 kg/m 3 . In this study, a lightweight panel was developed by a proper arrangement of radial bamboo curtain. The major and minor directions of a panel were the parallel- and perpendicular-to-its length direction, respectively. It was found that 1) the density of an OLBL panel could be reduced by about 20%; 2) the failure occurred in the bamboo node(s); 3) there was a significant difference in modulus of elasticity and modulus of rupture between two panel directions; and 4) there was a good relationship between the density and strength in the minor direction. 1 INTRODUCTION Formwork is an indispensable construction approach in buildings and bridges, which are usually made of steel, wood-based materials and bamboo-based materials (Smith and Hinze, 2009). The steel formwork is costly due to overweight. The wood-based formwork has the best performance, however the available resource is limited due to the restriction of deforestation (Hurd, 1998). Therefore, the bamboo-based formwork becomes an effective alternative material (Pallett, 1994). Bamboo, a fast growth plant of suitable characteristics for making formwork, is a superior resource to offset restricted supply of timber (Ni et al, 2016). The substantial density of bamboo is approximately 1.5 g/cm 3 similar to wood substance. The tensile strength of bamboo without node in the parallel-to-grain direction is twice as high as that of wood, and almost 3 times higher than that of common steel per unit weight. In order to meet the strength requirements of constructing buildings and bridges, the density of bamboo-based formwork is required up to 1.0g/cm 3 . It is well known, however, that the density of the material used has a significant impact on the cost of the formwork made of. As for the concreting practice, the formwork material takes about 6.0% of the total cost, and the formwork labor associated with the installation and removal accounts for 46.7% of the total cost (Baxi, 2011). That is why the reduction of the formwork density has been increasingly drawing attention. Due to the shape of bamboo materials, the bamboo-based formwork can be sorted into five categories, bamboo mat plywood, bamboo curtain plywood, bamboo particleboard, laminated bamboo lumber and laminated bamboo composite lumber (Jiang et al. 2002). To meet the surface properties of formwork, the overlaid laminated bamboo lumber (OLBL) is preferred. However, the absorption ability of bamboo-based formwork to concrete is less than one-seventh of that to steel formwork (Akmaluddin et al. 2015). Moreover, since the thermal conductivity coefficient of OLBL is quite small, it is suitable to be used in the
DEVELOPMENT OF LIGHTWEIGHT OVERLAID LAMINATED BAMBOO LUMBER FOR STRUCTURAL APPLICATIONS
May 17, 2023
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Related Documents
