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Introduction The use of practical methods for increasing water conveyance efficiency and optimal use of limited water resources is vital, especially in the world's arid regions, where water scarcity is always a concern. In that respect, efforts to reduce the cost of irrigation canals while maintaining the characteristics, technical standards, prevent damage to the structure, prevent leakage and loss of water at different stages of water transfer and distribution are of great interest to researchers (Abbasi, 2011). One of the solutions is to use pozzolanic materials, which replace a part of cement as cheap materials and thus reduce the finished price of cement. Changes in concrete fluidity and plastic behavior and hydration of cement are the most important physical changes that a pozzolan creates in concrete. Moreover, it can improve the strength and permeability of hardened concrete, resistance to thermal cracks, sulfates, and expansion (Luhar et al., 2019). Regarding using pozzolans to strengthen concrete, one of the most widely used plants in this field is bamboo. Bamboo is a plant that grows in tropical, subtropical and even temperate regions and any favourable regions in terms of ecological factors. On average, 20 million tons of this plant are produced annually in Asian and Latin American countries, which indicates its availability (Frías et al., 2012). Based on observations, Bamboo fibers increase the water absorption ratio (Xie et al., 2015). Furthermore, with the increase in the percentage of bamboo fiber, porosity is also growing (Da Costa Correia et al., 2014). However, Xie et al. (2015) stated that more than 25 to 35% of fiber use reduces stiffness (Xie et al., 2015). Taking these features into consideration, this study aimed to evaluate improvements in compressive strength, tensile strength, durability and elasticity of concrete with bamboo pozzolans. Methodology Bamboo straw was used for this research. The required bamboo plant was obtained from the farms of Guilan province, Rudsar city. In order to use it in concrete mixing design, it must be pulverized. Five Samples (control, 20% of bamboo particles, 30% of bamboo particles, 20% of bamboo nanoparticles and 30% of bamboo nanoparticles) were tested to investigate the mechanical characteristics of samples. One hundred fourteen samples were prepared for this purpose. Compressive and tensile strength, durability, elastic modulus and strain of different samples were measured in the 7th, 28th, 60th and 128th days. Results and Discussion The compressive and tensile strength of the control concrete in the period of 128 days were 289.11 and 33.97 kg/cm3, respectively. The strength in mentioned parameters grew through time in all samples, but the one with 20% of bamboo nanoparticles performed similarly to the control concrete. Having measured the durability, we realized that all samples containing pozzolan outperformed the control concrete in a sulphate environment, which means they had greater durability. Elasticity modulus was also measured. The modulus of elasticity in the samples containing bamboo particles was at least 38.6% lower than the control sample. Thus elasticity in all pozzolanic samples decreased considerably. Turning to strain results, samples with 20% and 30% of bamboo nanoparticles had a strain ratio of 146.58 and 122.74 compared to control concrete. The study reveals that the use of nano-scale bamboo particles made desirable changes in the elastic properties of the produced concrete. Conclusions Based on the results, it can be claimed that the sample containing 20% of bamboo nanoparticles has the potential to be used in the concrete industry. This pozzolan improved the compressive strength, tensile strength, durability and elasticity of concrete to an acceptable level. As a result, they can be benefitial, especially as a filler for expansion joints and contraction of concrete water transfer channels, which requires sufficient elasticity to prevent cracks during the expansion and contraction of concrete. [ABSTRACT FROM AUTHOR] |
