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The aim of this research was to investigate the physico-mechanical, thermal, and morphological properties of cement-bonded wood particleboards produced by using fly ash as a partial cement replacement and spruce planer shavings. Experimental single-layer cement-bonded wood particleboards produced using a target density of 1200 kg/m3, 1/3 wood-cement ratio, a dimension of 460 x 460 x 10 mm3 and 5 %, 10 %, 15 %, 20 % fly ash as cement replacement were tested for physical and mechanical properties in accordance with EN and ASTM standards. Moreover, morphological and thermal properties of the cement-bonded wood particleboards were analysed by using the scanning electron microscope and thermogravimetric analysis-derivative thermogravimetry. Test results indicated that the fly ash enhanced both the bending strength and water-resistance of the cement-bonded wood particleboards. Internal bond and screw withdrawal strengths tended to decrease as the fly ash content increased in the cement-bonded wood particleboards, but this decrease was not statistically significant. As the fly ash increased, the weight loss of the cement-bonded wood particleboards decreased in the thermogravimetric analysis because of the pozzolonic reaction of the fly ash with calcium hydroxide. In the scanning electron microscope, it was observed that calcium silicate hydrate gel increased, whereas calcium hydroxide decreased as the usage ratio of the fly ash increased in the cement-bonded wood particleboards

It is known that there is a correlation between hydration heat and physico-mechanical properties of wood based cement panels. Cement hydration is affected by many variables, such as chemical composition, water/cement ratio, wood/cement ratio, wood chemical properties, mineral additions and producing conditions. This study mainly aimed to investigate the effects of press temperature on some properties of three-layer cement bonded particleboard made from the particles of spruce (Picea orientalis) and poplar (Populus tremula). For this purpose, a total of 16 experimental board groups with 1200 kg/m3 target density and 1/3 wood-cement ratio were produced at the press temperatures of (20, 30, 40, 50, 60, 70 and 80) °C. As cement curing accelerator, CaCl2 was used at a rate of 5 % (cement weight basis). The physical, mechanical and thermal properties of the boards were determined. The results indicated that the press temperature substantially affected the properties of cement-bonded particleboard depending on the wood species. In the light of this study, the optimum temperatures in producing of cement-bonded particleboard were found as 40 °C for poplar wood and 60 °C for spruce wood.