Evaluation of Creep Characteristics of Single- Staple Furniture Joints Made of Different Wood Species

In this study, creep characteristics of single stapled furniture joints made of Scotch pine, alder and beech wood under three different load levels were considered. Load levels were determined as 30 %, 40 % and 50 % of the maximum load obtained as a result of static shear test before creep load and applied to wood joints. Laboratory test results showed that the highest creep deformation was observed in the joints made of Scotch pine with the lowest density, while the lowest creep deformation was observed in the joints made of beech with the highest density. In addition, the joints were exposed to lowest creep deformation at the 30 % load level, then the creep deformation of the joints increased at 40 % load level and it reached the highest value at 50 % load level. As a result of creep test, deformation in single stapled joints made of Scotch pine, alder and beech were determined as 2.74 %, 3.71 % and 4.37 % of the deformation that occurred as a result of static shear test performed before creep test, respectively. Ultimately, the overall average creep deformation value of a single staple wood joint under creep loading was determined as 3.61 %.

Rancang Bangun Aplikasi Permodelan Sambungan Kayu (Wood Joint) dengan Objek 3D Berbasis Android

Kayu merupakan bahan konstruksi yang banyak digunakan dalam industri mebel. Produk mebel tersusun atas sambungan kayu yang saling terhubung sehingga dapat membentuk suatu objek. Wood joint adalah keterampilan untuk menghubungkan dan menguatkan bagian dari kontruksi kayu dengan cara pemotongan tertentu pada ujung atau sisi dari bagian kontruksi kayu. Informasi mengenai model sambungan kayu saat ini umumnya hanya disajikan dalam bentuk gambar dua dimensi yang dimuat pada e-book ataupun media cetak, sehingga kurang menarik untuk dipelajari. Keterbatasan media informasi yang ada dapat diatasi dengan memvisualkan informasi mengenai model sambungan kayu melalui objek tiga dimensi. Informasi sambungan kayu dirancang ditampilkan melalui objek tiga dimensi beserta animasi menggunakan Unity3D. Aplikasi mobile berbasis Android yaitu WoodVenture dikembangkan pada penelitian ini yang diharapkan dapat memberikan pembelajaran membuat mebel untuk orang awam dan membantu pengguna mengetahui model sambungan kayu pada perancangan kerajinan mebel. Aplikasi WoodVenture memberikan pengetahuan tentang 40 model sambungan kayu melalui fitur animasi penyambungan model 3D. Aplikasi yang dihasilkan secara tidak langsung mengedukasi pengguna untuk mengetahui jenis model sambungan kayu yang dibuktikan melalui hasil kuesioner, yaitu sebesar 70% responden paham terkait konten yang terdapat pada Aplikasi WoodVenture.

Green Polyurethane Adhesives for Wood Bonding

The Green polyurethane adhesive system was prepared using two types palm oil polyol having different molecular weight ~1100 (GA) and ~ 2200 (GB) respectively, 4-4-diphenylmethane diisocyanate (MDI) and nanoclay fillers via in-situ process. Adhesives were applied on both sides of two untreated wood substrate using brushing technique for lap shear test. The attached substrate then undergoes the curing process for 24 hours at room temperature with relative humidity of 50±5%. The disappearance of NCO peak in the Fourier transform infra-red (FTIR) spectrum showed that MDI has completely reacted to form PU. Contact angle measurement proved that high wetting condition obtains from green polyurethane (PU) adhesive. PU adhesive wood joint improved in shear strength with addition of 1wt% nanoclay for both green polyol.

Influence of the moisture content on the fracture characteristics of welded wood joint. Part 1: Mode I fracture

Friction welding is a joining technique for wood materials. The positive aspects of this technique are the speed of processing and the absence of chemical or mechanical agents, but the welded joints are not water resistant. To understand better the effect of moisture on the fracture behavior of welded joints, their fracture characteristics have been investigated. The double cantilever beam specimens were tested, which permit to compute the mode I energy release rate of a welded joint. The results confirm the negative effect of moisture on the fracture properties of the joint. The data concerning the maximal tensile strength of the joining material were collected by uniaxial tests and implemented in a finite element model to establish a cohesive law, which describes the behavior of welded pieces in terms of moisture content.

Influence of the moisture content on the fracture characteristics of welded wood joint. Part 2: Mode II fracture

As a second part of this series, the present study also addresses the water resistance of joints obtained by friction welding. Here, the mode II fracture is in focus, that is, 4-points end-notched flexure specimens (4-ENF) were investigated with various moisture contents (MCs). The critical energy release rate was decreasing at higher MCs. The maximal shear strength of the joining material, as determined by torsion tests, was also affected by high MCs. The experimental data were implemented in a finite element model (FEM) based on the cohesive law to simulate the behavior of welded connection in 4-ENF tests. The FEM results describe well the experimental load-displacement curves.

Alternative experimental method to evaluate moment-carrying capacity of traditional wood-to-wood joint with small scale experiment

The effect of scale ratio was investigated on a traditional dovetail post-beam joint with dimensional analysis. The dimensionless parameters for moment (M) are modulus of elasticity (E) and length (L), and the moment of a small-scale model is equal to the value calculated by dividing the moment of a full-scale structure by the cubed ratio. The theoretical results of moment resistance were checked among dovetail post-beam joints of different sizes. The average maximum and yield moment resistance increased as the scale ratio increased. However, when both moment values were divided by the cube of the scale ratio, the values were similar among the different scale ratio joints. This result shows that the moment resistance was satisfied with the dimensional analysis within the tested scale ratio and it would be possible to predict the structural characteristics by testing specimens with other scales.

Analysis Design for Assembly by MTM-2 (Methods Time Measurement-2) for Wood Joints in Furniture

This research study assembly process of a study of Wood Joints with Motion Time Study MTM-2 (Methods Time Measurement-2) and DFA (Design for Assembly) an assessment of the ability to assembly in the Feeding and Fitting. with LUCAS Assembly Evaluation Method for the results of the assessment and find the good-bad points of the assessment was applied. Wood Joint Index for this analysis is the feeding and fitting should not exceed 2.5 The pivot of the three groups in terms of feeding Index did not exceed 2.5 The advantages of the assessments, when applied to the wood. In general, the nature of Wood Joints must rely on to tool help in almost all assemble of the joints. Each tool is the difficulty of performing it. And in the Entrance of the parts are in a bad score. Tolerance in the 0.2 to 0.3 mm at the Wood Joint this is limitation is that the scores of these problems. So both of these topics for Wood Joints may be more table to the assessment more accurate and led to the development process for next time.