Abstract:
Expansive soil needs to undergo treatment to be used as safe foundation soil for roads and buildings. From an environmental
conservation and economical point of view, the usage of agricultural and industrial wastes is the best option. In this study, the
e ects of utilizing plastic waste and marble waste dust on the engineering properties of expansive soils were examined. Various
laboratory tests were carried out on sampled expansive soil by adding 10, 15, and 20% of marble and 0.25, 0.5, and 0.75% of
5 × 8 mm2 plastic strips. e laboratory test results showed that there are good enhancements on strength parameters due to the
addition of marble dust and plastic strips. With an increase in percentages of marble dust and plastic strips, California Bearing
Ratio (CBR) values rise. With the addition of marble dust, uncon ned compressive strength (UCS) values increase linearly, while
they increase only up to 0.5% with the addition of plastic strips. As the proportions of marble dust and plastic strips increase, the
soil’s free swell and CBR swell are decreased signi cantly. is shows that environmental pollution waste marble dust and plastic
strips can be utilized to strengthen the weak subgrade soil and minimize its swelling properties. erefore, this study found out
that the expansive soil treated with polyethylene terephthalate (PET) plastic and marble dust can be used as a subgrade material
since it ful lls the minimum requirement needed by standards.
