Production and properties of a medium density wood-cement boards produced with oriented strands and silica fume

Vinicius  Castro  Gomes de; Mário  Souza  Rabelo de; Cláudio Henrique  Menezzi  Soares Del

Production and properties of a medium density wood-cement boards produced with oriented strands and silica fume

Autores

Vinicius Castro Gomes de

Mário Souza Rabelo de

Cláudio Henrique Menezzi Soares Del

Editor

Universidad del Bío Bío

Descripción

Wood-cement board (WCB) is a panel product that has the advantages of inorganic and organicmaterials. However, the main problems affecting the manufacture and use of WCB are the inhibitoryeffects of wood on the setting of cement and the high specific gravity of the final product. This paperexamines the potential of strand orientation and the use of silica fume (SiO2) to facilitate the productionof a medium density WCB from Pinus taeda. Oriented wood-cement boards (OWCB) weremanufactured with wood/cement (w/w) ratio of 1:1, specific gravity 850 kg/m3; and SiO2 content ascement replacement of 0%, 10% and 20%. The OWCB were tested for static bending (MOR andMOE) properties in parallel (//) and perpendicular ( ) directions; internal bond (IB); compressionstrength parallel to surface (CP); thickness swelling (TS) and water absorption (WA). The resultsshowed that replacement of cement with 10% of SiO2, increased MOE (//), MOR (//) and CP and,decreased WA and TS, and most importantly eliminated the inhibitory effect of wood on cement setting.The principle of strand orientation was effective to produce boards with anisotropy in the flexuralproperties ranging form 2.1 to 2.8 for MOR and 2.6 to 3.8 for MOE. However, boards had very low IBstrength and this shortcoming must be addressed in future research.