Experimental analysis of strength and durability properties of cement binders and mortars with addition of microfine sewage sludge ash (SSA) particles

Abstract

Generation of sewage sludge is increasing all over the world, and its safe disposal is becoming a serious concern. Utilization of this waste as a raw material for some products can lead to multiple advantages. Considering the physical and chemical properties of the sludge, it can be used as a replacement for cement as its properties are similar to those of cement. Moreover, the sludge is being incinerated for better workability. The purpose of this study is to utilize supplementary cementitious materials like sewage sludge ash as a replacement for cement for better properties like strength and durability. Incorporating such waste materials into concrete can reduce the use of cement, making it eco-friendly. During this investigation, the water-cement ratio was kept constant at 0.5. Different percentages (5,10,15,20,25) of microfine Sewage Sludge Ash (SSA) a being used as a replacement for the cement. Tests conducted during this analysis are compressive; setting time, rapid chloride permeable test (RCPT) and XRD (for the detection of the occurrence of crystalline material). The results show that the compressive strength of the mortar at 10% is higher than that of 20%. Cement binders and mortars could benefit from the usage of this waste material because it has a significant impact on their strength and durability.