A comparative study on opto-thermal properties of natural clay bricks incorporating dredged sediments

Brick industry is currently facing shortage of natural resources. Despite of this, the demand for construction bricks is continuously increasing. Alternative materials such as dredged sediments and solid organic waste have been recently proposed to replace natural clay in brick manufacturing. The potentials of dredged sediments to be incorporated into clay bricks are evaluated in this study by investigating the chemical composition of the mixtures and the opto-thermal properties of brick samples that differ for the dredged sediments’ content (10% in DS-10, 30% in DS-30, and 50% in DS-50). Chemical analysis highlighted that lower concentrations of heavy metals were proper of bricks incorporating dredged sediments. Negligible variations in thermal conductivity, thermal diffusivity, and specific heat were observed by increasing the amount of DS in the mixture. In particular, the thermal conductivity values ranged between 0.446 ± 0.027 W m-1 K-1 (DS-50) and 0.501 ± 0.028 W m-1 K-1 (DS-30). Conversely, the color shift value was found directly proportional to the concentration of DS as well as the spectral reflectivity to infra-red radiation. The reuse of dredged sediments as building material was demonstrated to be a solution to the problem of their disposal as well as of the scarcity of natural clay for brick production.