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Chapter 1 Bamboo as a Building Material 1.1Bamboo and bamboo construction 1.1.1Bamboo resources Bamboo grows widely in tropical and subtropical zones in the Asia-Pacific£¬Americas£¬and Africa.The Asia-Pacific bamboo area has the most abundant bamboo resources£¬where the bamboo forest accounts for 67% of the total amount.In this area£¬ bamboo has been utilized in daily life for a long history and still plays an important role in modern times.Bamboo is always regarded as the¡°wood for poor people¡±£¬since most of the bamboos are in natural growth and lack of high value-added utilization.However£¬several countries alone in the Asia-Pacific bamboo area are able to manage their bamboo forests intensively(Table 1.1). Among these countries£¬China has the most abundant bamboo resources in the world£¬with the bamboo forest and raw bamboo output accounting for about 1/4 and 1/3 of the global total£¬ respectively.More than 85% of the bamboo based panels are produced in China with the leading bamboo processing technology.However£¬ under the strict policy of protecting natural wood forests£¬ about 50% of the timber has been imported in the past years.As¡°substitute timber with bamboo¡±represents key national strategic initiative£¬it is of great significance to study how to properly use bamboo in building industry(Figure 1.1). Industrial bamboos£¬in standard form of panel or square£¬are regarded as idea l substitutes for timber.Since 1980s£¬the timber processing technologies have been introduced to the modification of bamboo£¬and series bamboo products parallel to their timber peers have been successfully developed. The representative bamboo panel variants include the plybamboo(including bamboo mat board£¬ bamboo curtain board£¬etc.)developed in the 1980s£¬the bamboo particleboard£¬laminated bamboo and bamboo-oriented strand board developed in the 1990s£¬the bamboo scrimber developed in the 2000s£¬as well as the flattened bamboo board and bamboo winding developed in the 2010s.The bamboo industry in China has moved towards a way of industrialized and high value-added utilization(Figure 1.2). Among the bamboo based panels£¬laminated bamboo and bamboo scrimber are widely used as decorative panels because of the good surface appearance.In 2012£¬China produced approximately bamboo flooring panels£¬of which around were made of laminated bamboo£¬and the rest were bamboo scimber and some other bamboo composites.Plybamboo is another successful product that has been widely used in packaging£¬concrete formwork sectors£¬and also structural members in building industry.As the earliest developed bamboo based panel£¬its production technologies have been very proven£¬making it own advantages of low cost and low technical requirement.By comparison£¬the bamboo particleboard and bamboo OSB are unable to achieve large-scale marketing.These two are developed£¬respectively£¬as products parallel to the wood medium-density fiberboard(MDF) and wood OSB£¬the two mainstream products in timber industry.However£¬unlike wood MDF and OSB£¬the bamboo particleboard and bamboo OSB are limitedly used in packaging£¬furniture and concrete formwork sectors. 1.1.2Environmental benefits of bamboo as local building material The local application of bamboo products has potential to improve the building sustainability.Compared with the wood£¬concrete£¬and steel in environmental and financial aspects£¬bamboo is considered to be a competitive building material under certain boundary conditions.A carbon emission calculation of the¡°Glubam¡±£¬a kind plybamboo parallel to the¡°Glulam¡±in timber industry£¬shows that the total carbon emission during the production is-261.00kg/m3£¬smaller than the-168.00kg/m3 of Glulam.However£¬long distance transportation will weaken the environmental advantage of bamboo.For example£¬an environmental impact calculation for the carbonized 1-layer plain pressed laminated bamboo board in the¡°cradle to gate¡±stage shows the transportation from the factory in China to the warehouse in the Netherlands accounts for 34.0% of the total eco-costs£¬and for the raw bamboo stem£¬the proportion of transportation section even reaches as high as 98.3%. In South China£¬there are some dominant bamboo species£¬such as the Phyllostachys pubescens£¬Dendrocalamus sinicus£¬etc.Meanwhile£¬this area is also an economically developed region of the country£¬where the building industry has stronger demand for ecological materials such as wood-based products.Compared with the wood-based material products£¬bamboo has higher heat transport and storage capacities£¬ as well as lower moisture transport and storage properties.A previous study by the author shows that in the hot and temperate climate regions£¬the room units enclosed with bamboo exterior walls show better performance than timber units with the same construction sizes£¬in terms of both energy consumption and indoor thermal environment.To some extent£¬it is conducive to the local application of bamboo in these areas where such c