Advanced composite cementitious materials with multifunctional properties can be designed and fabricated by incorporating fillers and inclusions through appropriate production, characterization, and assembly processes. These composites exhibit unique characteristics tailored for specific applications. In particular, cementitious composites with conductive particles and piezoresistive properties enable the development of structures and infrastructure with enhanced mechanical strength and amplified monitoring capabilities. They allow for the assessment of the structural integrity, as well as the monitoring of stress and strain, load variation, and the presence of incipient hazardous conditions throughout the lifespan of buildings. This enables more efficient management of maintenance, renovations, and structural modifications, ensuring improved safety and longevity of the constructed facilities. This paper describes the experimental results of the application of cement-based materials with carbon microfibers for the realization of structural beam elements. The samples are capable of self-diagnosis of internal non-uniformities due to defects or fractures, and to evaluate the variation in deformation.