Materials used for interior designs and works within buildings significantly influence fire safety.During a fire outbreak,these materials can either function as a barrier,slowing the spread or as a catalyst,accelerati...Materials used for interior designs and works within buildings significantly influence fire safety.During a fire outbreak,these materials can either function as a barrier,slowing the spread or as a catalyst,accelerating the fire.Among these materials,the role of wood,including engineering wood products,is crucial due to its variable calorific value.This paper aimed to determine the differences in calorific values of three wood derivatives:natural wood(Tieghemella heckelii,commonly known as Makore),plywood,and medium-density fibreboard(MDF).The study employed an experimental research design to analyse the combustion properties of the three wood types.Measurements of their calorific values were made using an oxygen bomb calorimeter following ASTM standards.Tieghemella heckelii exhibited the highest calorific value(18.4622 MJ/kg)and lowest ash content(0.43%-0.48%),making it the most energyefficient but posing higher fire risks.Plywood demonstrated moderate calorific values(16.3076-16.8227 MJ/kg)and ash content(1.76%-2.63%),providing a balance between efficiency and safety.MDF had the lowest calorific values(16.0921-16.3098 MJ/kg)and highest ash content(6.80%-7.22%),making it less efficient as a fuel source but highly suitable for fire-safe interior applications.Moisture content varied,with MDF exhibiting the lowest levels,enhancing its stability in diverse conditions.The findings indicated that Tieghemella heckelii is better suited for energy-intensive applications,while plywood and MDF are more appropriate for interior designs prioritising fire safety.The results emphasise the need for material selection based on specific application requirements and compliance with fire safety standards.展开更多
Lesser-utilised wood species may have the same or even superior performance for certain end-uses compared to the majority of Ghana’s most commonly used wood species.Avodire(Turraeanthus africanus)is a Lesser-utilised...Lesser-utilised wood species may have the same or even superior performance for certain end-uses compared to the majority of Ghana’s most commonly used wood species.Avodire(Turraeanthus africanus)is a Lesser-utilised wood species and is found in large quantities in forests of Ghana,but it is a less durable wood.Thermal treatment is a technique that can be used to enhance the durability of wood.The purpose of this research was to chemically and thermally treat Avodire wood samples to investigate the impact of the modification on its durability for interior applications.The wood samples were chemically modified to a weight percentage gain of 7.78±0.48 and thermally modified between temperatures 150˚C and 240˚C.Thermo-chemically modified samples exhibited resistance to decay and termite degradation.According to the study’s findings,samples that were not thermally treated and those that were thermally treated but not chemically modified had more weight loss and were less resistant to termite damage.Thermo-chemically modified samples at temperatures between 150˚C and 240˚C were effective for increasing the species’resistance to damage from termites and decay.展开更多
Wood anatomical structures of various tree species help identify the wood. The characteristics and composition of these structures affect their utilisation. In this work, the microstructure of Blighia sapida a lesser-...Wood anatomical structures of various tree species help identify the wood. The characteristics and composition of these structures affect their utilisation. In this work, the microstructure of Blighia sapida a lesser-known Ghanaian hardwood species using light microscope and scanning electron microscope (SEM) was studied. The relationship between the microstructure and some physical properties such as density, and bending strength were also studied. The anatomical features studied were fibre length, double fibre wall thickness, fibre proportion, vessel diameter and proportion, rays and axial parenchyma proportions. It was observed that the use of SEM in studying the anatomical or ultra-structural aspects of wood gives a clearer understanding of the features and structures found in wood. Anatomical features such as presence of crystals and absence of axial parenchyma in Blighia sapida are reported in the work. The study also established that Blighia sapida had a low water uptake even though it had vessel distribution of 12 vessels/mm<sup>2</sup>. Having not very distinct axial parenchyma may have accounted for the low water uptake. The presence of occluded pits could also account for the low water uptake and the fibre wall thickness may also account for a medium bending strength of 62.8 N/mm<sup>2</sup> at 12% moisture content.展开更多
Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of thre...Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of three European species. Sixteen randomly sampled specimens of each of the eight species (heartwood and sapwood) with dimensions 3 cm × 3 cm × 3 cm were exposed at various relative humidity conditions of 30%, 45%, 60%, 75% and 90% in a temperature and humidity-controlled climate chamber at a temperature of 25°C in accordance to German standard DIN 52182. The species are Albies alba, Fagus sylvatica and Picea abies which are European species and Amphimas pterocarpoides, Antiaris toxicaria, Canarium schweinfurthii, Celtis zenkeri and Cola gigantea are wood species from Ghana. Internal wood temperature and humidity were measured with datalogger. Samples were considered to have reached equilibrium at any given humidity when the daily weight changes were less than 0.1 mg according to German standard DIN 52183. After the last measurements of the weight changes, the samples were dried at 103°C until there was a constant weight. The five tropical hardwoods had low sorption values recorded and high sorption values for the European species and this could be attributed to differences in the microstructure of these woods.展开更多
文摘Materials used for interior designs and works within buildings significantly influence fire safety.During a fire outbreak,these materials can either function as a barrier,slowing the spread or as a catalyst,accelerating the fire.Among these materials,the role of wood,including engineering wood products,is crucial due to its variable calorific value.This paper aimed to determine the differences in calorific values of three wood derivatives:natural wood(Tieghemella heckelii,commonly known as Makore),plywood,and medium-density fibreboard(MDF).The study employed an experimental research design to analyse the combustion properties of the three wood types.Measurements of their calorific values were made using an oxygen bomb calorimeter following ASTM standards.Tieghemella heckelii exhibited the highest calorific value(18.4622 MJ/kg)and lowest ash content(0.43%-0.48%),making it the most energyefficient but posing higher fire risks.Plywood demonstrated moderate calorific values(16.3076-16.8227 MJ/kg)and ash content(1.76%-2.63%),providing a balance between efficiency and safety.MDF had the lowest calorific values(16.0921-16.3098 MJ/kg)and highest ash content(6.80%-7.22%),making it less efficient as a fuel source but highly suitable for fire-safe interior applications.Moisture content varied,with MDF exhibiting the lowest levels,enhancing its stability in diverse conditions.The findings indicated that Tieghemella heckelii is better suited for energy-intensive applications,while plywood and MDF are more appropriate for interior designs prioritising fire safety.The results emphasise the need for material selection based on specific application requirements and compliance with fire safety standards.
文摘Lesser-utilised wood species may have the same or even superior performance for certain end-uses compared to the majority of Ghana’s most commonly used wood species.Avodire(Turraeanthus africanus)is a Lesser-utilised wood species and is found in large quantities in forests of Ghana,but it is a less durable wood.Thermal treatment is a technique that can be used to enhance the durability of wood.The purpose of this research was to chemically and thermally treat Avodire wood samples to investigate the impact of the modification on its durability for interior applications.The wood samples were chemically modified to a weight percentage gain of 7.78±0.48 and thermally modified between temperatures 150˚C and 240˚C.Thermo-chemically modified samples exhibited resistance to decay and termite degradation.According to the study’s findings,samples that were not thermally treated and those that were thermally treated but not chemically modified had more weight loss and were less resistant to termite damage.Thermo-chemically modified samples at temperatures between 150˚C and 240˚C were effective for increasing the species’resistance to damage from termites and decay.
文摘Wood anatomical structures of various tree species help identify the wood. The characteristics and composition of these structures affect their utilisation. In this work, the microstructure of Blighia sapida a lesser-known Ghanaian hardwood species using light microscope and scanning electron microscope (SEM) was studied. The relationship between the microstructure and some physical properties such as density, and bending strength were also studied. The anatomical features studied were fibre length, double fibre wall thickness, fibre proportion, vessel diameter and proportion, rays and axial parenchyma proportions. It was observed that the use of SEM in studying the anatomical or ultra-structural aspects of wood gives a clearer understanding of the features and structures found in wood. Anatomical features such as presence of crystals and absence of axial parenchyma in Blighia sapida are reported in the work. The study also established that Blighia sapida had a low water uptake even though it had vessel distribution of 12 vessels/mm<sup>2</sup>. Having not very distinct axial parenchyma may have accounted for the low water uptake. The presence of occluded pits could also account for the low water uptake and the fibre wall thickness may also account for a medium bending strength of 62.8 N/mm<sup>2</sup> at 12% moisture content.
文摘Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of three European species. Sixteen randomly sampled specimens of each of the eight species (heartwood and sapwood) with dimensions 3 cm × 3 cm × 3 cm were exposed at various relative humidity conditions of 30%, 45%, 60%, 75% and 90% in a temperature and humidity-controlled climate chamber at a temperature of 25°C in accordance to German standard DIN 52182. The species are Albies alba, Fagus sylvatica and Picea abies which are European species and Amphimas pterocarpoides, Antiaris toxicaria, Canarium schweinfurthii, Celtis zenkeri and Cola gigantea are wood species from Ghana. Internal wood temperature and humidity were measured with datalogger. Samples were considered to have reached equilibrium at any given humidity when the daily weight changes were less than 0.1 mg according to German standard DIN 52183. After the last measurements of the weight changes, the samples were dried at 103°C until there was a constant weight. The five tropical hardwoods had low sorption values recorded and high sorption values for the European species and this could be attributed to differences in the microstructure of these woods.
