期刊缩写       MOKUZAI GAKKAISHI

期刊全称       MOKUZAI GAKKAISHI 木材学会志

出版国家       JAPAN

出版周期       Bimonthly

出版年份       1955

期刊ISSN       0021-4795

 

 

Journal of the Japan Wood Research Society.

 

 

Research Trends of Natural Adhesives

 

Synthetic resin adhesives such as formaldehyde-based resins have been used for manufacturing wood-based materials. However, in view of concern about global environmental problems and potential shortages of fossil resources, it is desirable to reduce the consumption of synthetic resin adhesives. Natural adhesives derived from bio-resources have been considered as alternatives to synthetic resin adhesives. Natural adhesives for wood are classified into saccharide-based, protein-based, aromatics-based, oil-based, natural rubber-based, and liquefied wood based-adhesives, etc. Several adhesives have been investigated in each group. Recent trends of natural wood adhesives are reviewed based on published research papers. Here I would like to summarize the kinds of natural substances, research methods, synthesis methods, resin properties, bond performance and evaluation methods.

 

Prediction of Internal Shear Capacity of Sugi CLT Panels

 

Cross-laminated timber (CLT) panels consist of several layers of lumber stacked crosswise and glued together on their faces. CLT panels are excellently applicable for timber buildings as slabs for horizontal structural members. Live load and dead load on CLT panels cause internal shear stress. Distribution of internal shear stress in CLT panels is affected by the modulus of elasticity of parallel layers. Rolling shear stress occurs in cross layers under shear force applied to CLT panels. Generally rolling shear strength is lower than the shear strength parallel to the grain. Few data of rolling shear strength of lumber exist. Internal shear capacity of several types of CLT panels was predicted by calculating the distribution of internal shear stress from the experimental rolling shear strength of sugi lumber. To verify the calculated shear capacity of several types of CLT cross sections, asymmetric four-point bending tests were carried out. The experimental shear capacity was found to be 12% lower than the average value of the rolling shear strength model for the lumber of the shear zone and was 16% higher than the minimum value of rolling shear strength model.