Experimental Study on the Effect of Nano Orion on the Strength of M35 Grade Concrete

Concrete remains the most widely used construction material worldwide due to its versatility, affordability, and strength. However, traditional concrete has inherent issues such as high permeability, microcracking, and limited resistance to harsh environments. These problems reduce its durability and lifespan, creating a need for innovative solutions that improve performance and sustainability. Nanotechnology has recently emerged as a promising approach to addressing these issues. Among various nanomaterials, Nano Orion, a Nano–silica–based additive, offers excellent pozzolanic reactivity, a high surface area, and the ability to improve pore structure. This study investigates the effects of Nano Orion as a partial cement replacement in M35 grade concrete, focusing on its mechanical properties, durability, and sustainability. The research used a systematic approach, with Nano Orion added at replacement levels from 0% to 5% by weight of cement. The M 35 mix was designed with a binder content of 400 kg/m³, a water–binder ratio of 0.40, fine aggregate (700 kg/m³), coarse aggregate (1200 kg/m³), and polycarboxylate ether (PCE) superplasticizer to ensure workability. All ingredients were verified according to IS standards before testing. Concrete specimens were prepared and tested for compressive strength, split tensile strength, and flexural strength. Results showed that adding Nano Orion significantly improved concrete performance, especially at an optimal dosage of 3%. Compressive strength increased from 43.8 MPa in the control mix to 54.6 MPa at 28 days (a 25% increase); split tensile strength rose from 3.32 MPa to 4.41 MPa (a 28% increase); and flexural strength increased from 4.48 MPa to 6.60 MPa (a 25% increase). Service life estimates increased from approximately 40 years in conventional concrete to around 70 years in Nano Orion–modified concrete under aggressive conditions. The study concludes that a 3% Nano Orion replacement optimizes both strength and durability while maintaining acceptable workability with the use of admixtures. From a sustainability standpoint, the results confirm that Nano Orion enables higher performance with less cement, thereby reducing CO₂ emissions and supporting green construction. These findings support the use of Nano Orion–modified M35 concrete as a durable and eco-friendly infrastructure material. Future research should explore large-scale field trials, combinations with other supplementary cementitious materials, and life-cycle assessments to fully realize Nano Orion's potential in sustainable building practices.