Research Activities: 2012

Dilation Characteristics of Rubberized Concrete
 
 Status Complete                 View Final Report: PDF
 
Sequential Number R342
 
Identification Number 00042523
   
Matching Research Agency

Missouri University of Science & Technology
 
Principal Investigator

Mohamed ElGawady
Associate Professor
Missouri University of Science and Technology
Rolla, MO 65409
(573) 341-6947
elgawadym@mst.edu
 
Student Involvement

One graduate student
 

Project Objective		 Rubberized concrete is a conventional concrete including scrap tire rubber as a partial substitution for mineral aggregates. Recent research showed that adding rubber to concrete significantly improves it viscous damping; hence, reduce its vibration and corresponding forces under earthquake ground motion. In order to use rubberized concrete, the dilation angle of rubberized concrete having different rubber content need to be determined. The objective of this proposal is to use triaxial tests to determine the dilation angle of concrete having rubber content ranging from 0 to 20% as a replacement of fine gravel.
 

Project Abstract		 Recently, the PI research group developed a structural system for
accelerating bridge construction. The system consists of precast post-tensioned concrete filled fiber reinforced polymer tubes (PPT-CFFT). However, the system has limited viscous damping.
Recent research showed that viscous damping of concrete can be increased by adding shredded rubber. To incorporate the rubberized concrete into PPT-CFFT, the factors that affect the behavior of confined rubberized concrete need to be quantified. One of the main parameters to
quantify the confinement is dilation angle. This research will use triaxial tests to determine the dilation angle of rubberized concrete having different rubber content and different confining pressure.
 

Relationship to other Research/Projects

The PI has one pending project to investigate the seismic behavior of rubberized concrete. He co-advise a PhD student at the University of South Australia where he investigates the behavior of rubberized concrete encased in FRP tubes.
   

Transportation-Related Keywords

 Accelerated bridge construction, rubberized concrete
   

Technology Transfer Activities

One technical presentation and/or technical paper
   

Project Deliverables

 A technical report
   

Anticipated Benefits

Approximately 60 million scrap tires in the U.S. end up in landfills every
year which take up valuable space in landfills. Scrap tires also provide breeding grounds for mosquitoes and rodents when stockpiled or illegally dumped. Moreover, scrap tires are a dangerous fire hazard that is notoriously difficult and costly to extinguish. In 2005, 750,000
scrap tires blazed for several months in Polk County in the State of Missouri and nineteen area fire departments were not able to extinguish the fire for several months. Recycling of scrap tires conserves valuable natural resources and reduces the amount of rubber entering landfill and
illegal dumps. Moreover, in the U.S., 36 states are required to design bridges for moderate to high seismic forces. Increase concrete damping will help the nation to build bridges that can sustain earthquake induced damage which will save tax payers billions of dollars related to earthquake damage. For example, the losses related to repair and replacement of bridges during Northridge (1994) was approximately $0.5 billion.

Milestones
Project Start Date: 05/01/2013
Project End Date:

12/31/2013