Nitrogen sorption porosimetry is a highly precise analytical technique used to measure the pore size distribution and surface area of materials, including cement and concrete. By adsorbing nitrogen gas onto the surface of the concrete at various pressures, this method provides detailed insights into the microstructural characteristics of the material. Understanding these properties is crucial for optimizing the durability and mechanical strength of concrete, especially under severe environmental conditions where resistance to permeability and structural integrity are paramount.