Investigation of the suitability of concrete infilled bamboo for structural performance in compression for low-cost building

Abstract

Various Engineering Scholars and Building construction materials and researchers have been doing experiments on investigating properties of Plain Bamboo, Concrete infilled Bamboo composite, and use of Bamboo to replace reinforcements in Concrete. Little has been disseminated on the Concrete infilled Bamboo with various concrete mix ratios. There are scarce and scanty documented and published information relating to the structural properties of Concrete infilled Bamboo as composite material. It is urgent to venture and understand through experimental investigations the Structural Properties of Concrete infilled bamboo to understand its structural properties to proof reliable usage when designing low-cost buildings, especially when considering axial compressive loading. Bamboo grows fast, and its readily available natural resource, with proven high strength and low weight to height ratio. For decades, Bamboo has been used as a rural building construction, and with recent innovations for domestic furniture. With recent research and innovations to look for alterative building materials to substitute concrete and steel, Bamboo Mechanical and structural properties have proven ideal for construction especially for low-cost houses units. Its major short fall however remains buckling, which is limits their usage in buildings subjected to compressive loads. This thesis outlines an experimental approach to investigate the properties, specifically the compressive strength when bamboo is infilled with concrete to form a composite material. Experimental investigation and results of the compressive strength of concrete infilled composite, with different concrete grades subjected to loads was experimentally investigated to appreciate the compressive strength of Concrete infilled Bamboo at different Bamboo samples lengths. This research mainly was based to assess the compressive strength of plane Bamboo, and concrete infilled Bamboo using varying concrete grades. The positive results from the experiment can outline an avenue and evidence for its suitability in expanding the usage of Bamboo as a construction material for low-cost shelter constructions. In this research paper, the compressive strength of plane Bamboo and concrete infilled Bamboo with concrete grades C12/15, C16/20 and C20/25 was investigated. Overall, there was marked improvement on the compressive strength of Concrete infilled bamboo culms. For Experimental tests done on plain Bamboo, the failure load was found to be decreasing with increasing Bamboo sample lengths. The axial load capacity of plain Bamboo at 0.2m sample length is 26.4% more than that at 1m length. Concrete infilled Bamboo with C15, C20 and C25 led to an increment of 58.7%, 103% and 139.1% of the compressive strength capacity compared to plain bamboo culms sample test length at 1m respectively; and 54.4%, 77.6% and 100.8% at Sample lengths of 0.2m. Concrete infills greatly improves the load capacity of identical bamboo culms. The failure load capacity was increasing when Bamboo sample lengths were infilled with Concrete, and the Load carrying capacity increases when Bamboo was infilled with concrete of higher grades. Bamboo infilled with concrete grade C25 has a large failure load than that infilled with concrete grade C20 and C15, signifying a higher ductility behaviour. From the study therefore, it can be concluded that concrete infill in bamboo can delay the buckling of the culms, and thus significantly improves the compressive strength capacity and ductility. There were observed differences between the experimental and the theoretical results of concrete infilled Bamboo. The difference in results could have come as experimental results were derived from actual laboratory experiments on the plain Bamboo and concrete infilled Bamboo under study. Theoretical “results" was just an application of the latest theories, formulae, and references on confined concrete to try to predict how it works, assuming its relative structural behaviour and performance. Finally, this research can be a resource for reference and formulating further innovations in Structural Engineering design to use Concrete infilled Bamboo composite as a building materials properties understood for effective design, repeatability, adoption for conventional construction and maintenance to meet the current need for innovative and new building materials. Key words: Plain Bamboo, Concrete infilled Bamboo, Compressive strength.