3D woven composites, due to the presence of through-thickness fibre bridging, have the potential to improve damage tolerance and at the same time to reduce the manufacturing costs. However, the ability to withstand damage depends on weave architecture as well as the geometry of individual tows. A substantial amount of research has been performed to understand in-plane properties as well as the performance of 3D woven composites exposed to impact loads, but there is limited research on the damage tolerance and notch sensitivity of 3D weaves and no work is reported on the damage tolerance of 3D weaves with a weft binding pattern. In view of the recent interest in 3D woven composites, the influence of weft binder on the tensile, open hole tensile, impact resistance and subsequent residual compressive strength properties and failure mechanisms of 3D woven composites was investigated against equivalent UD cross-ply laminate. Four different 3D woven architectures; layer-to-layer, angle interlocked, twill angle interlock and modified angle interlock structures were produced under identical weaving conditions. All the above mentioned tests were performed in both the warp and weft directions on 3D woven and UD cross-ply laminates. Stress concentration and yarn waviness due to through-thickness reinforcement led to lower mechanical properties compared with the UD cross-ply laminate. However, improved in-plane and damage tolerance properties of 3D woven composites under tensile loads were achieved by modifying the weave architecture. The influence of the weave architecture and binder yarn orientation on the notch insensitivity and damage tolerance of 3D woven composites was less significant for compressive loads. Despite the lower undamaged compression strength of 3D woven structures, their residual compressive strength was found to be superior to their equivalent UD cross-ply laminates. The lower rate of strength reduction in the 3D woven fabrics laminates was attributed to a crack bridging mechanism, effectively inhibiting delamination propagation.

Cette étude présente le développement d'une méthode expérimentale et numérique de caractérisation du comportement d'un matériau composite à renforts tissés, depuis l'échelle microscopique jusqu'au niveau macroscopique, en augmentant progressivement la complexité des géométries et des cas de chargement. Un nouveau modèle matériau numérique a été développé sous la forme d'un UMAT pour le logiciel éléments finis LS-DYNA. Ce modèle est capable de prédire un comportement linéaire ou non-linéaire, la déformation plastique, la rupture et l'endommagement progressif du matériau après rupture, tout en respectant les différentes restrictions imposées par le domaine industriel. Une formulation non-locale a été implémentée afin d'éviter les phénomènes indésirables de localisation de l'endommagement et d'offrir l'indépendance du modèle à la finesse du maillage. La première étape du processus de validation est la simulation des essais quasi-statiques sur des échantillons, ce qui permet de définir les paramètres numériques fondamentaux correspondant aux propriétés mécaniques et au comportement macroscopique du matériau étudié. Ensuite, les simulations d'impact assurent l'étude des modèles de dégradation. Une bonne corrélation a été obtenue pour les différents cas de chargement. / This study presents the development of an experimental and numerical material characterization method relying on the investigation of the material behavior of woven composites, from the microscopic scale up to the macroscopic level by increasing progressively the complexity of the geometries and load cases. Taking into account the different limitations imposed by the industrial and engineering fields, a new numerical mesh-insensitive material model has been developed as a UMAT for the explicit finite elements solver LS-DYNA. This model accounts for nonlinearity, plasticity, failure and post-failure damage in order to predict the macroscopic behavior and the damage tolerance of woven laminated composites. It includes also a smeared formulation to avoid undesirable localization phenomena. The first step of the validation process relies on the simulation of quasi-static coupon tests, which allows to set the fundamental numerical parameters corresponding to the effective material properties and to the macroscopic behavior observed experimentally. Then, the post-failure material degradation models have been investigated using the simulations of impact tests on elementary plates and on representative parts. A satisfying agreement has been obtained for the different load cases.

Ces travaux s’attachent à décrire et quantifier les mécanismes de ruptures des compositestissés 3D sous chargement de traction quasi-statique et à mettre en place une méthode de simulationnumérique adaptée et robuste, pouvant à terme être appliquée en bureau d’études.Dans cette optique, une étude expérimentale a été menée afin de quantifier la propagation defissures dans ces matériaux. Celle-ci a permis de mettre en place un scenario de rupture, entirant parti de la multi-instrumentation des essais. L’étude a également été effectuée sur deséprouvettes de géométries et de tailles variées et a mis en évidence d’importantes variations dutaux de restitution d’énergie avec les conditions d’essai. Un formalisme d’analyse et de modélisationintroduisant des longueurs internes a ensuite été présenté et adapté aux mécanismes derupture des composites tissés 3D. Ce formalisme est étayé par la recherche des mécanismes àl’aide de l’analyse des faciès de rupture. Les longueurs introduites ont ainsi été mises en relationavec les paramètres du tissage. Une méthode d’identification des paramètres a été proposée etles conséquences de ce comportement sur le dimensionnement de pièces composites discutées.Enfin, le transfert de ces résultats a été effectué vers des simulations numériques robustes. Desméthodes de régularisation des modèles d’endommagement continu ont été présentées et évaluéesà l’aune de leur capacité à assurer, d’une part, la robustesse des résultats et, d’autre part,la bonne retranscription des effets d’échelle expérimentaux. La prise en compte de ces considérationsnumériques et physiques nous a amené à proposé un modèle d’endommagement Non-Local.Une méthode d’identification des paramètres et de la longueur interne à partir des données expérimentalesa été proposée. / This work aims to describe and quantify the failure mechanisms of 3D woven composites underquasi-static tensile loading and to implement an adapted and robust numerical simulationmethod, that can be applied in industry. To this end, an experimental study was carried out toquantify the propagation of cracks in these materials. Thus, a crack propagation scenario wasestablished, thanks to the multi-instrumentation used during the tests. The experimental campaignwas carried out on specimens of various geometries and sizes and highlighted significantvariations in the fracture toughness with the test conditions. A modelisation framework introducinginternal lengths was then presented and adapted to 3D woven composites. This frameworkis supported by the identification of the failure mechanisms subsequent to the analysis of thecrack profile. The introduced lengths were thus related to the weaving parameters. A method foridentifying the parameters was proposed and the consequences of this behaviour on the designof the composite parts discussed. Finally, these results were transferred to robust numerical simulations.Regularisation methods of continuous damage models were presented and evaluatedin terms of their ability to ensure, on the one hand, the robustness of the results and, on theother hand, the correct transcription of experimental size effects. Taking into account these numericaland physical considerations led us to propose a Non-Local damage model. A method foridentifying the parameters and the internal length on experimental data was proposed.

3D textile performs offer a high potential to increase mechanical properties of composites and they can reduce the production steps and costs as well. The variety of woven structures is enormous. The algorithms based on the conventional weaving notation can only represent the possible woven structures in a limited way. Within the scope of this dissertation, a new weaving notation was developed in order to analyze the multilayer woven structures analytically. Technological solutions were developed in order to guarantee a reproducible preform production with commingled hybrid yarns. Terry weaving technique can be utilized to create vertical connections on carrier fabrics, which makes it suitable for the development of complex profiles. A double rapier weaving machine was modified with electronically controlled terry weaving and pneumatic warp yarn pull-back systems. Various spacer fabrics and 3D profiles were developed. A linear take-up system is developed to assure reproducible preform production with a minimum material damage. Integrated cutting and laying mechanisms on the take-up system provides a high level of automation.

This master thesis studies the recycling prospects of textiles. The textile industry contributes negatively to the global environmentthrough the release of greenhouse gases and consumption of resources. In order to achieve a circular textile industry, textiles must be recyclable by both chemical and mechanical means. Here, the focus is on mechanical extraction of staple fibres, particularly cotton, for reentry into yarn production. Experiments show that used, but undamaged, cotton sateen and cotton twill responds differently to abrasion with stochastic surfaces. Previous studies on the conventional shredding processes have shown positive impact from lubricants on extracted fibre lengths, by reducing inter-fibre friction. In the present study on abrasion, variables such as alignment of the weave pattern, lubrication and load are shown to have little to no impact on extracted fibre length, but notable effects on overall fibre quality. These analyses are supported by manual length assessment, electron micrographs and tensile tests using load cells. Furthermore, simple tests and observations on structured diamond surfaces constructed through chemical vapor deposition are promising for mechanical fibre release directly from a woven fabric. Suggestions are made on continued research in this field.

El presente proyecto de investigación se centra en la reducción de la generación de productos defectuosos mediante el uso de la metodología Lean Six Sigma. En primer lugar, se iniciará con el diagnóstico de la situación actual de la empresa en estudio donde se identifica que el FPY se encuentra con el valor de 88.08% del año en estudio, esto representa un total de 11.92% de desperdicio. La investigación contempla el uso de los pasos DMAIC, para poder atender las causas relacionadas al problema; la primera etapa es definir y consiste en la elaboración del Project Charter y del diagrama SIPOC para la caracterización del proceso Extrusión; como segunda etapa es medir y se emplean los histogramas para determinar la distribución de los rechazos, seguidamente se validará el sistema de medición. La etapa de analizar está enfocada a los resultados obtenidos y también se aplicará el FMEA para poder identificar y controlar los riesgos del proceso, en la etapa siguiente se aplicará las herramientas 5S y DOE. Como última etapa se emplearán cartas de control y la elaboración de procedimientos y actividades para la estandarización. Posterior a la implementación, se estima una disminución del índice desperdicio de 11.92% a 10.72%, dicho beneficio se reflejará en un impacto positivo sobre las ventas. De esta forma, las herramientas implementadas y los resultados conseguidos referidos en el artículo pueden servir de punto de partida a nuevos investigadores que desean aumentar la productividad en las empresas del sector. / This research project focuses on reducing the generation of defective products through Lean Six Sigma methodology. At first place, it will begin with the diagnosis of the current situation of the company under study, where FPY KPI is at 88.08% of the year under study, this represents a total of 11.92% of total waste. The investigation contemplates usage of DMAIC steps, to be able to attend the causes related to the problem; The first stage is to define and consists of the elaboration of the Project Charter and the SIPOC diagram for the characterization of the Extrusion process; as a second stage is to measure and histograms are used to determine the distribution of rejections, then measurement system will be validated. The analyze stage is focused on the results obtained and FMEA will also be applied to identify and control the risks of the process, in the next stage the 5S and DOE tools will be applied. As a last stage, control charts and the development of procedures and activities for standardization will be used. After implementation, a decrease in the waste rate is estimated from 11.92% to 10.72%, this benefit will be reflected in a positive impact on sales. In this way, the tools implemented and the results obtained referred in this article can serve as a starting point for new researchers who want to increase productivity in companies in the sector. / Trabajo de Suficiencia Profesional

This study aimed to explore the integration of varying angles in small-scale measurements and assess the light transmission performance of uncoated curtains. A total of four curtains were evaluated: blackout curtain samples 1 and 2 had a weft satin structure, while daytime curtain samples 3 and 4 consisted of a twill structure. The primary challenge was the inadequacy of a standardized test method for measuring the blackout effect, which led to inefficiencies and resource consumption for Company X. To address this, the study emphasized the need to investigate and establish a reliable and efficient evaluation method for uncoated curtains. By developing a standardized test method, it is possible to reduce waste material, labor costs, and resource consumption, enabling companies to operate more efficiently, sustainably, and responsibly. In the pursuit of understanding the blackout effect and evaluating the structural parameters of uncoated curtains, this study explored various test methods and parameters. More specifically, parameters such as air permeability, porosity, and thickness together with microscopic evaluation, were investigated to shed light on their influence on light transmission. The voids in the fabric were found to be a significant factor, along with porosity and air permeability, which demonstrated a correlation with lower values for the blackout curtains. The construction of the test method in a small-scale required a controlled space in the form of a lightbox. Light proofing of the box was required and successfully achieved in Prototype 1 using plywood, sealing strips, and fixtures, resulting in a lower lux value compared with the previous internal method. Objective measurements using the Konica CL-500A lux meter provided a repeatable and reliable test method with a lower tolerance value of 0,05 lx. The developed test method, theoretical Prototype 2, incorporates different sun angles by adjusting the curtain’s position, in the angles of 0°, 15°, 30°, 45° and 60°, and the rotation of the sample within 0° to 360° in intervals of 45°. The important parameters of weft density and the subsequent increase in weight were key factors in the results of light transmission, air permeability, and porosity. Furthermore, properties of the uncoated curtains such of continuous filaments and darker color showed a higher blackout effect. After the identification of complications with the lamp used in the measurement, there has been a focus on discussing the significance of a light diffuser. Additionally, alternative approaches to measure light transmission have been presented, such as digital image analysis and air permeability.

No description available.

’African Bamboo PLC’ has the vision to become the first and the leading bamboo-based floorboard producer in Africa with export markets in Europe and America. African alpine bamboo (Yushania alpina), common in the highlands of Ethiopia, was used to develop woven strand board (WSB) products. Research on thermal modification was part of the product development. Samples were mainly collected in Tetechia (6°33‘ 34‘‘ N 38°32‘25‘‘ W, 2,650-2,700 m a.s.l.), located in the Sidama region. Three culms each of two, three, four and five years of age were harvested. Samples were taken from the middle of each internode to determine the moisture content and density. Samples used to assess the effects of thermal modification were cut next to them. Further test specimens from different areas and other species such as the lowland bamboo (Oxytenanthera abyssinica) were also investigated. The thermal treatment was applied in a kiln with steam as an inert blanket to reduce oxidative processes. Eight modifications were performed at temperatures of 160 °C, 180 °C, 200 °C and 220 °C, at durations of three or five hours each. Mass loss, sorption behaviour, impact resistance, resistance to indentation and contents of chemical components were analysed for the modified and unmodified samples. Yushania alpina is a thin-walled bamboo with a maximum diameter of 6 cm, moisture content of up to 150 % and densities of between 0.5 g/cm² and 0.8 g/cm². Moisture content, diameter and wall thickness decreased from the bottom to the top of the culms, whereas density increased. Two year old bamboo had the lowest and three year the highest density. The mass loss followed an exponential trend, with about 2 % loss at 160 °C and 16 % at 220 °C. This mainly reflected the degradation of hemicellulose, which was fully removed at 220 °C. Extractive contents, at less than 5 %, fluctuated. Lignin amounted to 30 % and increased appreciably. Cellulose reached contents of about 45 % and decreased slightly at high temperatures. The chemical change, which was based more on the temperature than on the duration of treatment, influenced the sorption behaviour and mechanical properties most of all. The equilibrium moisture content was reduced by between 10 % to 40 %, depending on the climate and modification temperature chosen. This reduction stabilised between temperatures of 200 °C and 220 °C. The impact resistance of untreated bamboo was 3.8 J/cm², compared to only 1.4 J/cm² for modified samples. Resistance also differed between samples from the outer and inner part of the culm in the transverse section. The resistance to indentation declined also. Unmodified samples had 47 N/mm², compared to only 20 N/mm² for strongly modified samples. The results of the analysis and the experience gained indicate that temperatures between 180 °C and 200 °C, held for three hours, lead to the best results for woven strand board production using Ethiopian highland bamboo. / ’African Bamboo PLC’ setzt sich zum Ziel, als erstes Unternehmen Holzwerkstoffe aus Bambus nach Europa und Amerika zu exportieren. Afrikanischer Hochgebirgsbambus (Yushania alpina), welcher vor allem im Hochland von Äthiopien vorkommt, wurde dazu verwendet ”woven strand boards” (WSB) zu entwickeln. Untersuchungen zur thermischen Modifizierung waren dabei Bestandteil der Produktentwicklung. Die dafür notwendigen Bambusproben wurden hauptsächlich in Tetechia (6°33‘34‘‘ N 38°32‘25‘‘ W, 2650-2700 m ü. NN), einem Dorf in Sidama, entnommen. Es wurden dazu je drei Bambushalme der Altersklassen zwei, drei, vier und fünf Jahre geerntet. Proben für die Bestimmung von Holzfeuchte und Dichte wurden in der Mitte jedes Internodiums entnommen. Diese spielten als Referenzprobe eine große Rolle. Neben den Referenzprobekörpern wurden die jeweiligen Stücke für die thermische Behandlung heraus gesägt, wobei dies nach einer bestimmten Systematik erfolgte. Neben den Proben aus Tetechia wurden für die Untersuchungen zudem Proben aus anderen Gebieten und von einer anderen Art, dem Tieflandbambus (Oxytenanthera abyssinica), hinzugefügt. Die thermische Modifizierung erfolgte unter Wasserdampf, welcher oxidative Prozesse verhinderte. Insgesamt erfolgten acht Modifizierungen bei Temperaturen von 160 °C, 180 °C, 200 °C und 220 °C und einer jeweiligen Haltezeit von drei oder fünf Stunden. In Anbetracht der unbehandelten und behandelten Proben wurden der Masseverlust, die Bruchschlagarbeit, der Eindruckswiderstand und die chemische Zusammensetzung analysiert. Yushania alpina ist ein dünnwandiger Bambus mit Durchmessern bis zu 6 cm, Holzfeuchten bis 150 % und Dichten zwischen 0,5 g/cm² und 0,8 g/cm². Holzfeuchte, Durchmesser und Wandstärke verringerten sich mit der Halmhöhe, wobei die Dichte hingegen anstieg. Zweijähriger Bambus hatte die geringsten und dreijähriger Bambus die höchsten Dichten. Der Masseverlust folgte einem expontiellem Verlauf mit Werten von 2 % bei 160 °C und 16 % bei 220 °C. Er widerspiegelte den Abbau der Hemicellulose, welche bei 220 °C schon nicht mehr vorhanden war. Exktraktgehalte fluktuierten mit Werten unter 5 %. Der Ligningehalt lag bei ungefähr 30 % und stieg merklich an. Der Cellulosegehalt erreichte Werte von etwa 45 %, wobei die Cellulose bei höheren Temperaturen leicht abgebaut wurde. Die chemischen Veränderungen, welche maßgeblich von der angewandten Temperatur statt der Behandlungsdauer beeinflusst wurden, wirkten sich auf das Sorptionsverhalten und mechanische Eigenschaften aus. Je nach ausgesetztem Klima und erfolgter Modifikation wurde die Ausgleichsfeuchte der Proben um 10 % bis 40 % reduziert. Die Abnahme der Ausgleichsfeuchte stabilisierte sich im Temperaturbereich von 200 °C bis 220 °C. Die Bruchschlagarbeit des unbehandelten Bambus betrug 3,8 J/cm², die des behandelten nur 1,4 J/cm². Die Bruchschlagarbeit variierte unabhängig von der Modifikation zwischen dem inneren und äußeren Abschnittes innerhalb des Halmquerschnitts. Der Eindruckswiderstand nahm mit der thermischen Behandlung ebenfalls ab. Unbehandelte Proben hatten 47 N/mm², während die modifizierten Proben nur noch 20 N/mm² aufwiesen. Anhand der Ergebnisse und erworbenen Erfahrungen lies sich schlussfolgern, dass Temperaturen zwischen 180 °C und 200 °C bei einer Haltezeit von drei Stunden für die thermische Modifizierung von Äthiopischem Hochlandbambus in Bezug auf die Entwicklung von ”woven strand boards” empfehlenswert waren.

’African Bamboo PLC’ has the vision to become the first and the leading bamboo-based floorboard producer in Africa with export markets in Europe and America. African alpine bamboo (Yushania alpina), common in the highlands of Ethiopia, was used to develop woven strand board (WSB) products. Research on thermal modification was part of the product development. Samples were mainly collected in Tetechia (6°33‘ 34‘‘ N 38°32‘25‘‘ W, 2,650-2,700 m a.s.l.), located in the Sidama region. Three culms each of two, three, four and five years of age were harvested. Samples were taken from the middle of each internode to determine the moisture content and density. Samples used to assess the effects of thermal modification were cut next to them. Further test specimens from different areas and other species such as the lowland bamboo (Oxytenanthera abyssinica) were also investigated. The thermal treatment was applied in a kiln with steam as an inert blanket to reduce oxidative processes. Eight modifications were performed at temperatures of 160 °C, 180 °C, 200 °C and 220 °C, at durations of three or five hours each. Mass loss, sorption behaviour, impact resistance, resistance to indentation and contents of chemical components were analysed for the modified and unmodified samples. Yushania alpina is a thin-walled bamboo with a maximum diameter of 6 cm, moisture content of up to 150 % and densities of between 0.5 g/cm² and 0.8 g/cm². Moisture content, diameter and wall thickness decreased from the bottom to the top of the culms, whereas density increased. Two year old bamboo had the lowest and three year the highest density. The mass loss followed an exponential trend, with about 2 % loss at 160 °C and 16 % at 220 °C. This mainly reflected the degradation of hemicellulose, which was fully removed at 220 °C. Extractive contents, at less than 5 %, fluctuated. Lignin amounted to 30 % and increased appreciably. Cellulose reached contents of about 45 % and decreased slightly at high temperatures. The chemical change, which was based more on the temperature than on the duration of treatment, influenced the sorption behaviour and mechanical properties most of all. The equilibrium moisture content was reduced by between 10 % to 40 %, depending on the climate and modification temperature chosen. This reduction stabilised between temperatures of 200 °C and 220 °C. The impact resistance of untreated bamboo was 3.8 J/cm², compared to only 1.4 J/cm² for modified samples. Resistance also differed between samples from the outer and inner part of the culm in the transverse section. The resistance to indentation declined also. Unmodified samples had 47 N/mm², compared to only 20 N/mm² for strongly modified samples. The results of the analysis and the experience gained indicate that temperatures between 180 °C and 200 °C, held for three hours, lead to the best results for woven strand board production using Ethiopian highland bamboo. / ’African Bamboo PLC’ setzt sich zum Ziel, als erstes Unternehmen Holzwerkstoffe aus Bambus nach Europa und Amerika zu exportieren. Afrikanischer Hochgebirgsbambus (Yushania alpina), welcher vor allem im Hochland von Äthiopien vorkommt, wurde dazu verwendet ”woven strand boards” (WSB) zu entwickeln. Untersuchungen zur thermischen Modifizierung waren dabei Bestandteil der Produktentwicklung. Die dafür notwendigen Bambusproben wurden hauptsächlich in Tetechia (6°33‘34‘‘ N 38°32‘25‘‘ W, 2650-2700 m ü. NN), einem Dorf in Sidama, entnommen. Es wurden dazu je drei Bambushalme der Altersklassen zwei, drei, vier und fünf Jahre geerntet. Proben für die Bestimmung von Holzfeuchte und Dichte wurden in der Mitte jedes Internodiums entnommen. Diese spielten als Referenzprobe eine große Rolle. Neben den Referenzprobekörpern wurden die jeweiligen Stücke für die thermische Behandlung heraus gesägt, wobei dies nach einer bestimmten Systematik erfolgte. Neben den Proben aus Tetechia wurden für die Untersuchungen zudem Proben aus anderen Gebieten und von einer anderen Art, dem Tieflandbambus (Oxytenanthera abyssinica), hinzugefügt. Die thermische Modifizierung erfolgte unter Wasserdampf, welcher oxidative Prozesse verhinderte. Insgesamt erfolgten acht Modifizierungen bei Temperaturen von 160 °C, 180 °C, 200 °C und 220 °C und einer jeweiligen Haltezeit von drei oder fünf Stunden. In Anbetracht der unbehandelten und behandelten Proben wurden der Masseverlust, die Bruchschlagarbeit, der Eindruckswiderstand und die chemische Zusammensetzung analysiert. Yushania alpina ist ein dünnwandiger Bambus mit Durchmessern bis zu 6 cm, Holzfeuchten bis 150 % und Dichten zwischen 0,5 g/cm² und 0,8 g/cm². Holzfeuchte, Durchmesser und Wandstärke verringerten sich mit der Halmhöhe, wobei die Dichte hingegen anstieg. Zweijähriger Bambus hatte die geringsten und dreijähriger Bambus die höchsten Dichten. Der Masseverlust folgte einem expontiellem Verlauf mit Werten von 2 % bei 160 °C und 16 % bei 220 °C. Er widerspiegelte den Abbau der Hemicellulose, welche bei 220 °C schon nicht mehr vorhanden war. Exktraktgehalte fluktuierten mit Werten unter 5 %. Der Ligningehalt lag bei ungefähr 30 % und stieg merklich an. Der Cellulosegehalt erreichte Werte von etwa 45 %, wobei die Cellulose bei höheren Temperaturen leicht abgebaut wurde. Die chemischen Veränderungen, welche maßgeblich von der angewandten Temperatur statt der Behandlungsdauer beeinflusst wurden, wirkten sich auf das Sorptionsverhalten und mechanische Eigenschaften aus. Je nach ausgesetztem Klima und erfolgter Modifikation wurde die Ausgleichsfeuchte der Proben um 10 % bis 40 % reduziert. Die Abnahme der Ausgleichsfeuchte stabilisierte sich im Temperaturbereich von 200 °C bis 220 °C. Die Bruchschlagarbeit des unbehandelten Bambus betrug 3,8 J/cm², die des behandelten nur 1,4 J/cm². Die Bruchschlagarbeit variierte unabhängig von der Modifikation zwischen dem inneren und äußeren Abschnittes innerhalb des Halmquerschnitts. Der Eindruckswiderstand nahm mit der thermischen Behandlung ebenfalls ab. Unbehandelte Proben hatten 47 N/mm², während die modifizierten Proben nur noch 20 N/mm² aufwiesen. Anhand der Ergebnisse und erworbenen Erfahrungen lies sich schlussfolgern, dass Temperaturen zwischen 180 °C und 200 °C bei einer Haltezeit von drei Stunden für die thermische Modifizierung von Äthiopischem Hochlandbambus in Bezug auf die Entwicklung von ”woven strand boards” empfehlenswert waren.