Lightweight Treated Soil As a Potential Sustainable Pavement Material

Abstract

Recycling of poor soil becomes very important when good-quality construction materials are limited. This paper investigates the properties of lightweight treated soil such as strength properties based on the stress-strain behaviors, durability by simulating the freeze-thaw cycle (FTC), and evaluation of the road performance when lightweight treated soil was used as a subbase layer. Lightweight treated soil was made by mixing dredged soil waste, cement, air-foam, and water with the determined proportion. Test specimens were prepared with various cement contents and air-foam contents. Several series of unconfined compression tests, FTC tests, and thermal conductivity tests were then conducted. From the results of the experiments, it is observed that the strength of lightweight treated soil increased with an increase in cement content, but decreased with an increase in air-foam content or number of FTCs. The thermal conductivity of lightweight treated soil decreases with increasing air-foam content. The resilient modulus of lightweight treated soil was determined from a repeated load triaxial test to predict the fatigue and rutting life of a road. Based on the pavement performance life, recycled dredged soil using the air-foam stabilization method could be used as a sustainable pavement material.