Behavior of lightweight-foamed soil reinforced by waste fishing net and its design guideline

Abstract

Lightweight-foamed soils are promising new geomaterials that can be used when the lateral earth pressure and settlement need to be reduced. Lightweight-foamed soil typically consists of dredged soils, cement, and air foam. Extra additives could be used to enhance the performance of lightweight-foamed soils, and waste fishing nets are materials that can be used for tensile reinforcement of geomaterials. In this study, a waste fishing net was used in lightweight-foamed soil, and several laboratory tests were conducted to optimize the composition of lightweight-foamed soils in terms of water content, cement ratio, air foam ratio, and net type. A dredged soil in-situ was sampled to use and a waste fishing net was retreated for laboratory experiments. The waste fishing net cut into pieces and some were unthreaded. A form generator was used to produce air foam. The comprehensive evaluation of lightweight-foamed soil reinforced with waste fishing net was performed in terms of the sample preparation time, rheology, unit weight, and strength associated with lightweight-foamed soils. The results showed that lightweight-foamed soils reinforced with waste fishing net provided a peak strength similar with unreinforced one, but having higher critical strength. Finally, the normalized factor (NF) was used to develop a design guideline for lightweight-foamed soils.