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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