Examining the Required Cement Content

Cement is an essential ingredient in concrete. The hydration products formed when cement reacts with water provide concrete with its strength. If a concrete mixture contains too little cement, the specified compressive strength may not be achieved. On the other hand, mixtures containing too much cement can also experience problems. In a recent Federal Highway Administration (FHWA) study, researchers examined bridge deck performance in several states, and they found that bridge deck cracking increases as compressive strength increases. Arkansas Highway and Transportation Department (AHTD) specifies a minimum compressive strength of 4000 psi at 28 days for bridge decks and a minimum cement content of 6.5 bags (611 lbs.) of cement per cubic yard. In TRC 0603, researchers measured concrete strengths of five bridge decks. The results showed that most Arkansas bridge decks are achieving their design strength (4000 psi) by 7 days of age. Therefore, strength is not the reason for requiring 611 lbs. of cement.

Language

• English

Project

• Status: Active
• Funding: $247109
• Contract Numbers:

  TRC1602

• Sponsor Organizations:

  Arkansas State Highway and Transportation Department

  Planning and Research Division, P.O. Box 2261
  Little Rock, AR  United States  72203
• Project Managers:

  McKenney, Christopher

• Performing Organizations:

  University of Arkansas, Fayetteville

  Board of Trustees
  Fayetteville, AR  United States 
• Principal Investigators:

  Hale, W

• Start Date: 20160101
• Expected Completion Date: 20171231
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Admixtures; Bridge decks; Cement; Cement content; Compressive strength; Cracking; Hydration; Service life
• Geographic Terms: Arkansas
• Subject Areas: Bridges and other structures; Design; Highways; Materials;

Filing Info

• Accession Number: 01580355
• Record Type: Research project
• Source Agency: Arkansas State Highway and Transportation Department
• Contract Numbers: TRC1602
• Files: RiP, STATEDOT
• Created Date: Nov 5 2015 12:13PM