Victor Bivens

Date of Award

Summer 8-2020

Document Type


Degree Name

Master of Science (MS)


Civil Engineering


This thesis includes the structural enhancement study on the flexible or semi-rigid design of geopolymer mortar (GPM) to address tensile cracking commonly found at the invert of reinforced concrete pipes. Concrete pipes are often subjected to harsh sewer conditions, which eventually spread to the reinforcement skeleton through the resulting cracks and corrode it to cause premature structural failure of the pipe. Therefore, this added flexibility to the pipes’ rigid material will not only serve to limit corrosion of the steel reinforcement within the pipes but will also aid in increasing the structural stability of the pipe in its entirety. The suggested material for this semi-rigid design is additionally beneficial due to its use of recycled ingredients. Class F fly ash accounts for most of the material’s mass while fibers (steel, polyvinyl alcohol ‘PVA,’ and nylon) are used for their contributions to the geopolymer mortar’s overall flexibility. An alkali solution (sodium hydroxide, NaOH and sodium silicate, Na2SiO3) defines the mixture’s aqueous solution. These inexpensive and mostly recycled materials can directly reduce costs for the piping industry while also reducing emissions caused by the creation of the clinker used in Portland Cement Concrete. By improving overall concrete pipe stability and tensile strength, prolonging the life cycles of steel reinforcement and using recyclable waste materials as base ingredients, the research outcome for semi-rigid pipes made by flexible GPM supports a financially and environmentally green shift in the future of pipe networking.