From Trees to Wood and Beyond: A Brief Look Into Wood Structure / Vom Baum zum Wald und darüber hinaus. Ein kurzer Ausflug in die Holzstruktur

2021 ◽  
pp. 202-213
Author(s):  
Alan Crivellaro ◽  
Flavio Ruffinatto
Keyword(s):  
Wood Structure

Research on Chemical Modification of Wood of Fast-Growing Poplar

2013 ◽  
Vol 749 ◽  
pp. 461-465
Author(s):  
De Jun Shen ◽  
Chang Hai Yu ◽  
Zhen Xing
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Structural Material ◽  
Chemical Modification ◽  
Orthogonal Test ◽  
Low Molecular Weight ◽  
Wood Structure ◽  
Optimum Conditions ◽  
Fast Growing ◽  
Performance Requirements

This topic is considered to modify the fast-growing Poplar to improve the properties, in order to fully meet the performance requirements for the structural material. This study aims to improve the dimensional stability and some other mechanical properties through impregnated with the low-molecular-weight PF resin. Through design orthogonal test in different mole ratio of Formaldehyde and Phenol, different amount of NaOH and PVA, we make PF resin to impregnate Poplar and pressing into laminated timber to measure bonding strength, MOR, MOE. The study indicated that: the optimum conditions of the low molecular weight PF resin for modify Poplar are: mole ratio of Formaldehyde and Phenol is 2.4, mole ratio of NaOH and phenol is 0.05, amount of PVA is 3% of the phenol. Under this condition Poplar specimen got the biggest increase in various properties and it can satisfy the requirements of the outdoor wood structure.

Comparison of mechanical properties of thermally modified wood at growth ring and cell wall level by means of instrumented indentation tests

Holzforschung ◽  
2009 ◽  
Vol 63 (4) ◽  
Author(s):  
Stefanie Stanzl-Tschegg ◽  
Wilfried Beikircher ◽  
Dieter Loidl
Keyword(s):  
Mechanical Properties ◽  
Cell Wall ◽  
Thermal Treatment ◽  
Mechanical Performance ◽  
Growth Ring ◽  
Beech Wood ◽  
Thermal Modification ◽  
Wood Structure ◽  
Instrumented Indentation ◽  
Indentation Tests

Abstract Thermal modification is a well established method to improve the dimensional stability and the durability for outdoor use of wood. Unfortunately, these improvements are usually accompanied with a deterioration of mechanical performance (e.g., reduced strength or higher brittleness). In contrast, our investigations of the hardness properties in the longitudinal direction of beech wood revealed a significant improvement with thermal modification. Furthermore, we applied instrumented indentation tests on different hierarchical levels of wood structure (growth ring and cell wall level) to gain closer insights on the mechanisms of thermal treatment of wood on mechanical properties. This approach provides a variety of mechanical data (e.g., elastic parameters, hardness parameters, and viscoelastic properties) from one single experiment. Investigations on the influence of thermal treatment on the mechanical properties of beech revealed similar trends on the growth ring as well as the on the cell wall level of the wood structure.

Juniper wood structure under the microscope

Planta ◽  
2015 ◽  
Vol 241 (5) ◽  
pp. 1231-1239 ◽  
Author(s):  
Konstantin G. Bogolitsyn ◽  
Ivan N. Zubov ◽  
Maria A. Gusakova ◽  
Dmitry G. Chukhchin ◽  
Anna A. Krasikova
Keyword(s):  
Wood Structure

scholarly journals Growth performance and wood structure of wavy grain sycamore maple (Acer pseudoplatanus L.) in a progeny trial

2021 ◽  
Vol 78 (1) ◽  
Author(s):  
Mona Quambusch ◽  
Cornelia Bäucker ◽  
Volker Haag ◽  
Andreas Meier-Dinkel ◽  
Heike Liesebach
Keyword(s):  
Growth Performance ◽  
Vegetative Propagation ◽  
Seed Orchard ◽  
Breeding Systems ◽  
Acer Pseudoplatanus ◽  
Wood Structure ◽  
Progeny Trial ◽  
Plus Tree ◽  
Sycamore Maple ◽  
Figure Type

Abstract • Key message Wavy grain, a rare figure type of wood, leads to highly priced timber in Acer pseudoplatanus L. The influence of this trait on growth performance and its causes are not known. Analyzed wavy and straight grain sycamore maple progenies show comparable growth performance in a field trial. Stability of wavy grain after vegetative propagation is confirmed and genetic inheritance indicated. • Context Wavy grain is a rare figure type of wood resulting from undulating fiber growth that leads to a decorative and highly priced timber in Acer pseudoplatanus L. with top positions on auction sales. Nevertheless, neither the influence of this trait on growth performance is known, nor have the causes been disentangled. • Aims Our objectives were to find out if wavy grain figure influences growth parameters essential for log quality and to gain insight into the causes of wavy grain by the analysis of a progeny trial and a seed orchard. • Methods In a progeny trial with 30-year-old F-1-offspring from selected wavy grained and straight grained trees, trunk diameter, tree height, and trunk shape were evaluated. Additionally, 21 trees of the trial and selected plus tree-grafts of a seed orchard were felled and analyzed for occurrence and intensity of wavy grain structure. • Results No effect of the wavy and straight grain parentage on growth was observed in the progeny trial. Of the felled trees, over 30% showed evidence of wavy grain compared to rare occurrence in natural stands. Wood structure analysis of plus tree scions confirmed the stability of wavy grain after vegetative propagation. • Conclusion Wavy grain seems to be genetically inherited, and there seems to be no statistically significant difference in commercially relevant traits in the progeny. This highlights the value of including wavy grain as a desired attribute in breeding systems of maple.

Plans of Observation and Wood Structure

2019 ◽  
pp. 3-5
Author(s):  
Flavio Ruffinatto ◽  
Alan Crivellaro
Keyword(s):  
Wood Structure

Exploration of the Strategies in Civil Engineering to the Safety Evaluation and Reinforcement Technique of Wood Structure of Ancient Architecture in Huizhou

2012 ◽  
Vol 568 ◽  
pp. 71-75
Author(s):  
Qiang Sun ◽  
Wen He
Keyword(s):  
Quality Improvement ◽  
Statistical Analysis ◽  
Civil Engineering ◽  
Safety Evaluation ◽  
Field Investigation ◽  
Wood Structure ◽  
Traditional Architecture ◽  
Existing Problems ◽  
Technical Status ◽  
Ancient Wood

According to the field investigation of Huizhou ancient wood structure and statistical analysis of related documents, this paper expounded the main technical status and existing problems of Huizhou ancient wood structure safety evaluation and reinforcement and reconstruction, and put forward the research content of Huizhou ancient wood structure safety evaluation and reinforcement and reconstruction countermeasures, discussed the safety evaluation and reinforcement renovation the feasibility of the method for Huizhou traditional architecture reconstruction and quality improvement to provide technical reference.

Cooperation Pullout Test of Double Self-Tapping Screws in Wood Structures

2011 ◽  
Vol 374-377 ◽  
pp. 2520-2524 ◽  
Author(s):  
Gang Shi ◽  
Jian Xing Zhang ◽  
Yuan Qing Wang ◽  
Hui Juan Huang ◽  
Zheng Hong Zhang
Keyword(s):  
Experimental Study ◽  
Pullout Test ◽  
The Self ◽  
Connection Strength ◽  
Wood Structure ◽  
Wood Structures ◽  
Pullout Resistance ◽  
Loading Tests ◽  
The Common ◽  
Strength And Stiffness

In this paper, the experimental study on the self-tapping screw’s pullout resistance in the wood structure was conducted. Domestic ordinary screws were used together with imported or domestic wood to fabricate 6 screw connection specimens in wooden walls. Then monotonic loading tests were conducted and it can be concluded that, the common round screw connection strength mainly depends on the failure mode, the lack of cooperation effect significantly influences the strength of screw connections, and the dispersion of screw connection stiffness is high. So, to obtain formulae for the self-tapping screw connection strength and stiffness by further experimental study will be very necessary.

Sign in / Sign up

Export Citation Format

Share Document