Shear tests were conducted on screwed joints with decayed main members, and the degradation of shear performance of screwed joints by wood decay was investigated. The differences between decayed and control specimens in yield load (Py), and maximum load (Pmax) were both significant at the 1% level, while the difference in the initial stiffness (Ks) was not significant at the 5% level. The extent of

Wood cell walls have complex ultra-structures, in which cellulose microfibrils are surrounded by a hemicellulose–lignin matrix. This is the first paper to discuss the effect of cell wall on the pyrolytic reactivity of hemicellulose and cellulose in wood by using Japanese cedar (Cryptomeria japonica, a softwood) and Japanese beech (Fagus crenata, a hardwood), along with isolated xylan and glucomannan

Poplar plants with peculiar characteristics grow extensively and naturally in the Northern Hemisphere, and such poplar is the main timber material in Xinjiang, China. However, poplar has defects that affect its ultimate bearing capacity. This study investigates the flexural behavior of the timber members from poplar. Three lengths of basalt fiber-reinforced polymer (BFRP) strips were used to strengthen

In structural timber tests, unintended failure mechanisms occur frequently in specimens and their results are called censored data. There are two censored data analysis: censored maximum likelihood estimation (CMLE) and Kaplan–Meier (KM) method. In this study, the precision of the censored data analysis was investigated to determine the characteristic value, 5th percentile value, of the structural

Cross-laminated timber (CLT) is an innovative engineering wood product made by gluing layers of solid-sawn lumber at perpendicular angles. The commonly used wood species for CLT manufacturing include spruce-pine-fir (SPF), douglas fir-larch, and southern pine lumber. With the hope of broadening the wood species for CLT manufacturing, the purposes of this study include evaluating the mechanical properties

Lignin-free wood has been successfully developed via a two-step chemical treatment while maintaining its inherent hierarchical structure. The first step was alcoholysis which was conducted using ethylene glycol, and whose condition was optimized by monitoring the removal of lignin using infrared spectroscopy. The second step was bleaching wherein the delignification proceeded from the surface to the

The purpose of this study was to measure each color of three sections of wood with instruments, and to examine whether there were differences between each color of three sections. The total number of tree species measured was 60, with the same number of conifers and broadleaf trees. A test piece, which was a cube with one side of 34 mm, was prepared for each tree species. End grain, edge grain, bark

A novel method for estimating the wood moisture content above the fiber saturation point (FSP) is proposed, and the method performance is confirmed. Previous studies have highlighted that there is a negative linear correlation between the specific dynamic Young’s modulus (log (E/ρ)) and tangent loss (log (tanδ)) of clear small wood specimens. We confirm that this correlation can be obtained for air-dried

A study was carried out to investigate the release of volatile organic compounds (VOCs) during drying of plantation Pinus sylvestris grown in China and naturally grown Pinus sylvestris from Russia. Our purpose was to provide basic information that can help wood processing mills set their VOCs emission limits and control the exhaust gas within such limits. During conventional drying of the plantation

In this study, a colloidal suspension, composed of polymethylsilsesquioxane (PMS) and Cu-containing nanoparticles (CuNP), was prepared through simple neutralization reaction using sodium methyl siliconate (SMS) and CuCl2 solutions. The nano-structure of CuNP was investigated by TEM and the results showed that lamellar crystal Cu(OH)2 with size of around 10 nm was imbedded in PMS nano-particle. The

The aim of this study is to propose a method for measuring the mass of wood lumber in piles through a vibration test. Air-dried sitka spruce (Picea sitchensis Carr.) pieces with 1500–1600 mm length (L), 105 mm width (R), and 105 mm thickness (T) were used as specimens. We created a model of wood lumber inside a pile. A load 10 times that of the specimen was applied to the specimen, and vibration was

Unfinished interior wood members in wooden cultural heritages undergo severe discoloration by fungal attack during the summer rainy season. The prevention of fungal discoloration is crucial in the conservation of wooden cultural heritages. It is important to investigate discoloration properties of major mold and stain fungi under different relative humidity conditions to prevent discoloration damage

NO2 sorption ability of cedar (Cryptomeria japonica) timbers was evaluated using a new measuring system that was developed in our previous study. Four drying conditions were applied, namely natural drying and three kinds of kiln-drying at 45, 60, and 105 °C. Aeration experiments were conducted using discoid specimens which had a thickness in the longitudinal direction of 1.5 mm, and a diameter of 10 mm

In Japanese households, it is customary to walk barefoot on wood floors. This study sought to clarify the physiological effects produced via tactile application of sugi (Cryptomeria japonica) to the sole of the feet, using the brain and autonomic nervous activities as indicators. Twenty-seven female university students (mean age, 21.9 ± 1.9 years) participated in this study. Oxy-hemoglobin (oxy-Hb)

In this study, the mechanical performance of melamine–urea–formaldehyde (MUF) resin plywood composed of an orthotropic material, which is used as a structural material in liquefied natural gas (LNG) cargo containment systems (CCSs), is evaluated. With a decrease in temperature, the plywood changes from ductile to brittle under compressive loads; thus, it may fail to distribute the compressive loads