Doctoral Dissertations

Keywords and Phrases

Chip Seal; Crumb Rubber; Masonry; Rubberized Concrete; Scrap Tires; Sustainable Materials


“The United States needs to mine billions of tons of raw natural aggregate each year. At the same time, millions of scrap tires are stockpiled every year. Therefore, replacing natural aggregate with recycled crumb rubber aggregate will be beneficial to the construction industry and environment. This research aimed to investigate the feasibility of using recycled rubber in new construction applications. Based on size, recycled rubber was selected to match its natural counterpart. Different ratios of recycled crumb rubber were used as a fine aggregate replacement in concrete masonry units (CMUs) where the rubberized units showed a lower unit weight, higher ultimate strain, and better durability. In addition, the thermal conductivity of rubberized masonry units decreased with increasing the rubber content resulting in a reduction in heating energy consumption. In a different application, recycled crumb rubber was used as a full or partial replacement of coarse aggregate in chip seal surfacing where it shows better retention especially with longer curing time. The rubberized chip seal had a rougher surface which increases driving safety. Environmentally, the toxic heavy metals leached from the rubberized chip were below that of the EPA drinking water standards with a significant reduction of heavy metal leaching when rubber was used with emulsion in the form of chip seal. The third application was utilizing the waste of scrap tire processing in a form of rubber- fiber powder (RFP) as a sand replacement within cement mortar. RFP was used as an additive to provide more corrosion resistance and less heat of hydration of cement mortar. Incorporating RFP within plastering mortar disclosed that RFP can be used as an eco-friendly additive to provide better crack resistance, thermal and acoustical insulation as well as noise reduction”--Abstract, page iv.


ElGawady, Mohamed

Committee Member(s)

Myers, John J.
Sneed, Lesley
Baur, Stuart Werner, 1965-
Chandrashekhara, K.


Civil, Architectural and Environmental Engineering

Degree Name

Ph. D. in Civil Engineering


This research was supported by Missouri Department of Natural Resources


Missouri University of Science and Technology

Publication Date

Spring 2019

Journal article titles appearing in thesis/dissertation

  • Mechanical Characterization of Concrete Masonry Units Manufactured with Crumb Rubber Aggregate
  • Thermal Characterization of Cleaner and Eco-Efficient Masonry Units Using Sustainable Aggregates
  • Retention Behavior of Crumb Rubber as An Aggregate in Innovative Chip Seal Surfacing
  • Texture and Design of Green Chip Seal Using Recycled Crumb Rubber Aggregate
  • Leaching Assessment of Eco-Friendly Rubberized Chip Seal Pavement
  • Durability Properties of Cleaner Cement Mortar with By-Products of Tire Recycling
  • Recycled Additive to Improve Freeze-Thaw Durability of High Fly Ash Content Mortar
  • Eco-Friendly Thermal and Acoustic Retrofitting of Masonry Elements Using Rubber-Fiber Powder


xxv, 340 pages

Note about bibliography

Includes bibliographic references.


© 2019 Ahmed Adnan Gheni, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 12013

Electronic OCLC #