Engineering Master’s Thesis Explores Bending Behavior of Concrete Slabs with Plastic PET Waste as Sand Alternative

The master’s thesis of Zahraa Ahmed Sabbar, a student in the Department of Civil Engineering at the Faculty of Engineering, University of Maysan, was discussed on Thursday, December 12, 2024, in the Graduate Hall of the college. The thesis, titled “Investigating the Bending Behaviour of Concrete Slabs Containing Plastic PET Waste as an Alternative to Sand,” explores innovative methods for incorporating polyethylene terephthalate (PET) waste into concrete mixtures.

The discussion was conducted by a committee of distinguished academics, including:

• Professor Dr. Abbas Abdelmadjeed Dayab Allawee – President
• Assistant Lecturer Dr. Samer Muhammed Jaseb – Member
• Assistant Lecturer Dr. Mortaza Abbas Abd Ali – Member
• Professor Dr. Abbas Odah Dawood – Member and Supervisor

The research investigates the effects of using PET waste as a partial replacement for fine aggregates in concrete, focusing on both mechanical and physical properties as well as the bending behavior of reinforced and unreinforced concrete panels enhanced with polypropylene fibers.

The study is divided into two main parts:

1. Evaluation of Concrete Properties:
   This section examines the impact of various PET replacement ratios—0%, 5%, 10%, 15%, 20%, 30%, and 50%—on the concrete’s properties. Additionally, 1.5% polypropylene fibers were incorporated into the concrete mixtures to further assess their influence on material performance.
2. Bending Behavior Analysis:
   Fourteen concrete slabs, each measuring 1500 × 500 × 80 mm, were tested. These slabs were divided into two groups:
   • Reinforced Slabs: Seven slabs with varying levels of PET replacement.
   • Unreinforced Slabs: Seven slabs similarly tested for PET replacement levels, alongside two reference slabs.

The study identified optimal PET replacement ratios of 10% and 15%, which demonstrated significant improvement in the mechanical properties and bending behavior of the slabs. These findings highlight the potential for sustainable alternatives in concrete production by incorporating recycled materials such as PET waste, contributing to both environmental conservation and advancements in construction technology.