International Congress on Recent Innovations in Engineering, Science and Technology - Istanbul - Turkey (2019-10-31)

Moisture induced stresses in cross laminated timers (CLT) made from hydrothermally modified wood
Abstract In the current research work, moisture gradients and moisture induced stresses (MiS) were inves-tigated in Cross Laminated Limber (CLT) bearing hydrothermally treated fir wood in its laminations. Wood-en blocks were cut from fir wood planks and hydrothermally treated in a stainless steel reactor at temperature of 170°C for a holding time 30 min. The panels were made with combinations of untreated and treated wood with one and two treated layers laid up on both sides of the CLT samples. Afterwards, the CLT panels were exposed to wetting (from RH 88% to 32%) and drying (from RH 32% to 88%) cycles to provide moisture gradients as well as moisture induced stresses. The results showed that, the hydrothermal treatment reduced the moisture gradients. It was also revealed that the moisture gradient due to wetting and drying cycles was reduced by the hydrothermal treatment. The high the moisture gradients as well as the high the moisture in-duced stresses were recorded on the untreated panels.
Assoc. Prof. Behbood Mohebby, Mr. Vahid Broushakian