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This study examines the effect of adding different dosages of nontitanium (NT) and nano-silica (NS) ranging from 0.5 to 4% by weight of binder materials on ultra-high-performance geopolymer concrete (UHPGC). The material’s feasibility was evaluated using slump flow measurements. A detailed analysis of its compressive strength (CS), transport properties, and sulfate attack was conducted. The addition of 2.5% NS and 4% NT improved the CS and transport properties of UHPGC compositions, creating a denser and more durable microstructure with enhanced interfacial bonding, as confirmed by the microstructure study. According to this study, the most effective doses for enhancing UHPGC performance in various aspects are 2.5% NS and 4% NT. The CS was recorded at 198.7 MPa for 2.5% NS mixes and 197.6 MPa for 4% NT mixes for ages test 28 days. These findings provide valuable insights into developing and utilizing advanced, high-efficiency UHPGC for sustainable and sturdy construction techniques.

This investigation aims to study the effect of replacing 100% of fine and coarse aggregates with heavyweight aggregates and adding nano titanium (NT) and nano silica (NS) on shielding against radiation and on the mechanical and transport properties of heavyweight high‐strength concrete (HWHSC). In this study, 20 mixes were prepared that included the use of hematite and steel slag (SS) aggregate with NS or NT used as additions to mixes by the ratio 1% and 3% from cement weight. To study the effect of the total replacement of aggregates and the addition of nanomaterials (NMs) on the properties of HWHSC, to study engineering properties the slump, compressive strength, splitting tensile strength, flexural strength, and modulus of elasticity were applied. Density, chloride permeability, sorptivity coefficient, water permeability, and microstructure tests were also performed. To study the efficiency of shielding against radiation, linear attenuation coefficient, mass attenuation coefficient, mean‐free path, half‐value layer, and tenth‐value layer of different gamma‐ray sources of radiation 137Cs 662 (keV) and 60Co 1332 (keV) were applied. The results showed that the 100% SS and hematite replacement as coarse and fine aggregates with 3% (NS or NT) achieved the best mechanical and transport properties compared to other mixtures. While the highest density of the string containing hematite and SS was achieved with 3% of NT, with a density of 3384 kg/m3. The highest compressive strength of more than 116 MPa was achieved for the included mixture of 3% NS. The highest attenuation of gamma‐ray radiation was achieved with the application of hematite and SS aggregates with 3% of NT. [ABSTRACT FROM AUTHOR]

Many environmental problems can be ascribed to agricultural waste. Millions of tonnes of agricultural waste, such as banana and date palm trees, are produced worldwide. Such waste is converted and recycled as natural fiber. On the other hand, a major problem of high-strength concrete (HSC) is the sudden failure at the ultimate capacity of concrete. To solve these problems, this work investigated the effects of using natural fiber waste to improve the brittle behavior of HSC. The natural fiber was treated with chemical solutions before recycling in concrete. Seven HSC mixes were designed; three mixes contained banana fiber (BF), the other three incorporated palm leaf sheath fiber (PLSF), and the last one was the control mix. The respective fiber volume fractions of BF and PLSF were 1%, 2% and 3%, and the aspect ratio was 100. The fresh and hardened properties, such as slump, compressive, tensile, flexural strengths and modulus of elasticity, of HSC with natural fiber were determined. In addition, microstructure analysis of natural fibers and HSC with natural fiber was performed through scanning electron microscopy. No substantial improvement was observed in the compressive strength of the natural fiber. The tensile strength of HSC increased when up to 2% PLSF was used. Compared with BF, PLSF yielded a higher enhancement in HSC properties. Both fibers demonstrated improved efficiency in enhancing the brittle behavior of HSC. The effects of recycling an agriculture fiber in concrete are reported. Using PLSF in HSC yields higher improvement compared with using BF. BF and PLSF achieve high efficiency in arresting the crack developed in HSC. [ABSTRACT FROM AUTHOR]