Improved Strength and Stiffness Characteristics of Cross-laminated Poplar Timber Columns

Abstract

Timber apart from being a cheap construction material possesses numerous environmental advantages, which makes it one of the highly sought construction material, particularly for moderately loaded residential structures. Timber due to the easy cultivation of timber trees can be made available in abundance. Thus, can serve as an efficient and sustainable building material, provided its structural potential is tapped fully. In this study, various performance improvement techniques have been used for enhancing the axial strength characteristics of a timber specie (Poplar), that is available in abundance, in the northern part of India. Different binding/wrapping techniques have been adopted to utilize Poplar in a laminated form, known as cross-laminated timber (CLT). It has been found that a strength improvement of about 20% can be achieved in CLT short columns by simply bolting the laminates together, while as this improvement can be as high as 32%, provided cold form steel (CFS) sheets are used for strengthening these CLT timber columns. Similarly, in the case of long CLT columns, a strength improvement of 50% is attained when a double cross helix of fibre reinforced polymer (FRP) cloth is adopted for the strengthening purpose. Furthermore, this study is aimed at utilizing small unused, otherwise, waste timber logs/pieces in columns with strength improvement techniques for improved axial strength performance.