Performance evaluation of lime–cement–copper slag–rice husk ash composite as a pavement construction material

Abstract

ABSTRACT This work focuses on the development of new composite materials using industrial wastes such as copper slag (CS) and rice husk ash (RHA), treated with lime (L), and cement (C). For the mixing, the content of CS, RHA, L and C are varied in a range from 51%-100%, 20%-100%, 4%-14% and 4%-10%, respectively. To study the performance of the composite materials, various tests, such as the California bearing ratio (CBR), permeability, and durability tests, were carried out. To study the microstructure characteristics of the developed composite materials, FE-SEM analysis tests were performed. The results indicated that the CBR value decreases with the increase in the binder contents (L and/or C) and RHA contents for both unsoaked and soaked conditions for all the mixes (M3–M14). Out of all the mixes (M3–M14), the highest CBR is obtained for the mix M11, having both L and C. For the unsoaked condition, this value is 21.13% and for the soaked condition, this value is 38.66%, 57.99%, and 65.90% for curing periods of 4, 7, and 28 days, respectively. The CoP of composite materials decreased with an increase in the contents of binding materials (L and/or C) and RHA with the period of curing (7, 14, and 28 days) for all 12 mixes (M3–M14). Out of all the 12 mixes (M3–M14), the highest value of CoP is obtained for mix M3 and the lowest values of CoP are obtained for mix M14, which are 3.22 × 10−4 and 6.58 × 10−5 cm/s, respectively, at 28 days of curing period. According to IRC standards, the results of the durability tests are adequate.