L’abstracció sensorial i mimètica de l’escriptura del cos:

The overall purpose to this research thesis was the evaluation of the use of Bambusa Blumeana, an Indonesian species of bamboo, as a reinforcement material for structural concrete in residential housing. From previous studies on bamboo and bamboo reinforced concrete, along with laboratory testing the following conclusions, along with future work recommendations have been established.

7.1. Conclusions

 After extensive research through already available literature on bamboo replacing steel as a reinforcement material in concrete, clear conclusions that bamboo can in fact be used as reinforcement in a residential concrete house were made. Factors such as tensile strength, availability of bamboo, design calculations, and costing have all been considered and this lead to theoretical viability of bamboo reinforced concrete. However, water absorption is an unfavourable inherent material limitation which can lead to poor bonding between the concrete and bamboo, and cracking of the concrete during the curing process. This needs to be rectified before bamboo can be used as a reinforcement material for concrete.

 Laboratory material property tests were performed on Bambusa Blumeana, proving that it had a high tensile strength as is needed in a reinforcement material. Ultimate tensile stress reached as high as 172.70MPa. Tests showed that the species had naturally low moisture content at 8.80%, along with a low water absorption rate and dimensional variation compared with other bamboos. These material tests concluded that Bambusa Blumeana appeared to be a suitable species of bamboo to use as a replacement to steel in reinforced concrete.

 Due to the tensile strength of bamboo compared with steel, along with the known fact that natural fibres hold a tendency to be unpredictable under differing loading conditions, the reinforcement capabilities of bamboo shall only be considered for small residential houses with a maximum of 2 stories. Any building with a greater height than this should be strictly designed to standards with steel reinforcement as to ensure maximum safety.

 Laboratory pull-out testing of the bamboo after treatment showed that covering a bamboo rod with an impervious material does not allow for any water transfer between the rebar and the concrete mixture during the curing period, therefore eliminating any cracks due to dimensional increase in the bamboo. The bituminous paint coating, and the epoxy with fine sand coating both surpassed expectations of bond strength, showed no sign of concrete

cracking during curing, and had simple application techniques. All of which point to the liability of these treatments. Un-coated bamboo also had optimistic bond strength, as little to no bond was expected due to the dimensional change. Further research into modifying the concrete blend with admixtures could be performed to determine perhaps an even more simple approach to bamboo reinforced concrete.

 The cost analysis performed on the treatment methods and overall process of bamboo reinforced concrete also showed liability in the replacement method. Although the analysis was performed via a global trade website, the materials required will be harder to acquire in 3^rd world community situations. Factors such as transport pathways and island distribution need to be considered. Also, the application process for the coatings turned out to be quite tedious, it was simple but took longer than expected. In a large scale production, applying coatings by hand will need a large amount of labour and will reduce the cost effectiveness. It will however be beneficial to the national economy as it will create local jobs. As the

bituminous paint coating can locally be derived from by-products of the already established coal industry in Indonesia, it is the obvious choice of coating.

 Finally, from the above statements, it can be concluded that coated bamboo rods can be used as a viable form of reinforcement for concrete. The facts that they are a low costing, easy to manufacture and renewable material make the reinforcement option sustainably sound. However, this is based on the principles outlined in this thesis, mainly bamboo’s tensile strength and the use of treatments to provide water absorption resistance. Further research must be conducted to create a standardised statement confirming the liability of bamboo reinforced concrete.

7.2. Future Work

Conclusions of this thesis state that that bamboo shows potential as a renewable reinforcement material, however there is still work to be performed on the subject. The following

recommendations have been designed for future work efforts to further research the viability of bamboo reinforced concrete.

 Now that it has been determined that the coatings applied eliminate any size fluctuation throughout the curing process, the next step shall be designing the implementation of treated bamboo into structural components. Slabs, beams, columns, and perhaps

foundations could now be designed. Consideration of prior research on timber reinforced components need to be taken, e.g. previous results on bamboo reinforced beams have been shown to increase their loading capacity almost 30% when doubly reinforced, along with the elastic modulus being more than double that of a singly reinforced beam (Sevalia, Siddhpura and Agrawal, 2013).

 After the design process, fabrication and testing of these elements can begin. Factors such as element cracking and ultimate load strengths should be considered, along with shear strengths and load combinations.

 The life cycle of these components should be considered. No long term effects of the chemical alkali-silica reaction upon the bamboo have been considered. Further long term testing needs to be performed to determine the design life of bamboo reinforced concrete.

 Depending on the desire of technical results, strain gauges can be placed on the bamboo as to determine the specific elastic modulus of Bambusa Blumeana. More specific observations throughout testing may be performed such as elongation distribution during tensile tests.

This will help determine whether bamboo undergoes a uniform elongation whilst under tension and in turn will provide beneficial information for the design process.

 Furthermore, if bamboo reinforced concrete was to be implemented on an industrial scale, a standardization of material qualities shall have to be arranged. E.g. implementing a

straightness tolerance on bamboo culms to ensure even distribution of load bearing.