Claudio Del Menezzi^1,2,3, Antonio Pizzi^2,*, Siham Amirou², Xuedong Xi^4,5

Journal of Renewable Materials, Vol.11, No.2, pp. 539-553, 2023, DOI:10.32604/jrm.2022.024971

Abstract

This article presents the first applied results of using citric acid in combinations with a melamine-urea-formaldehyde (MUF) resin for bonding wood veneers. The chemical reactions involved are shown based on a MALDI ToF analysis of the reaction of the MUF resin with citric acid. The preliminary results of the physical and mechanical properties of the LVL prepared are also presented. Veneers from Populus sp were used to manufacture 5-layer laminated veneer lumber (LVL) of small dimensions. Five combinations of the amount of citric acid, MUF spread rate and pressing parameters were tested. LVL bonded with 20% of citric acid +… More > Graphic Abstract

Zhongping Xiao¹, Chen Li^1,2, Biqing Shu¹, Shukai Tang², Xinghuan Yang², Yan Liu^2,*

Journal of Renewable Materials, Vol.11, No.1, pp. 245-255, 2023, DOI:10.32604/jrm.2023.020751

Abstract Fracture is a common failure form of poplar laminated veneer lumber (LVL). In the present work, we performed an experimental study on the mode-I along-grain interlaminar fracture, mode-I cross-grain interlaminar fracture, and mode-II interlaminar fracture of poplar LVL. We investigated stress mechanisms, failure modes, and fracture toughness values of the different fracture types. The experimental results revealed that the crack in the mode-I along-grain interlaminar fracture specimen propagated along the prefabricated crack direction, and the crack tip broke. The mode-I cross-grain interlaminar fracture specimen had cracks in the vertical direction near the prefabricated crack. In the mode-II interlaminar fracture specimen,… More >

Yan Liu¹, Yanfei Guo¹, Xufeng Sun^1,*, Meng Gong²

Journal of Renewable Materials, Vol.8, No.9, pp. 1111-1127, 2020, DOI:10.32604/jrm.2020.09575

Abstract Poplar Laminated Veneer Lumber (Poplar LVL) is a new type of engineering materials with high strength, good reliability and small variability. Poplar LVL is manufactured from the fast-growing poplar, which is widely used in packaging, furniture and others, however, is rarely adopted in construction. In order to explore the feasibility of poplar LVL trusses in construction of roof, four 4.5-m-span Fink-and-Howe trusses were designed and assembled, which were made of poplar LVL with bolted- and tooth-plated connections. Vertical static loading on the upper chord joints of a truss was imposed by self-balancing test device. The mechanical properties of trusses were… More >