Research Topic:Strength and Durability of Waste Based Geopolymer Stabilized Subgrade Soil with PET Strip Reinforcement

Problem Statement:
Medical Waste Incineration ashes are rich in calcium oxide although they may have a deficiency in aluminosilicate compounds [1]. Promising results in terms of strength development are found when incineration ash is used in concrete in combination with cement [2]. The leachability of heavy metals of the incineration ash is reduced below the allowable limits once stabilized with cement and converted into geopolymers with alkali activators [1, 2]. Fly ash from coal- based power plant, rich in aluminosilicate compounds, is one of the most important supplements of Portland cement. Moreover, reinforcing the stabilized soil by PET (Polyethylene-terephthalate) bottle strips may be an alternative to improve the characteristics of subgrade soil as well as reducing the waste materials [3].
In Bangladesh, the average medical waste generation rate is 1•63–1•99 kg/bed/ per day [4]. In April 2020, at least 14, 500 tons of waste from health care was generated across the country, on average, 206 tons per day in Dhaka city alone [4]. Approximately, 4.0 billion PET bottles and jars are produced each year in Bangladesh of which nearly 3.40 billion of PET bottles are released yearly to the natural environment after one-time use [5]. These waste materials can be an effective alternative to improve the strength characteristics of soil. Stabilization of problematic soil by cementitious materials gives better results [6-8]. However, use of cement is a growing concern as this industry is a major source of greenhouse gas generation. Approximately 5–7% of global CO2 emissions are caused by the cement plants [9]. As such, utilizing PET bottle strip as a reinforcing agent with a combination of alkali activated incineration ash and coal based flyash could yield an effective solution for improvement of weak road subgrade soil.

Fund Allotted:4,10,000/-

Objectives:
a. To investigate the durability and engineering properties of soil on stabilizing with incineration ash, fly ash and alkali activators
b. To investigate the physical and engineering properties of stabilized soil reinforced by PET bottle strips.

Duration:01 year

Expected Outcomes:
This study is expected to provide information on the strength and durability of alkali-activated incineration ash and fly ash stabilized subgrade with PET strips reinforcement. The possible outcome of the research will promote the valorization of wastes that have challenges for disposal. This project will help develop human resources as an MSc student may get his degree as a part of this research work.