Title: 90 Minutes: Love It or Lose It?

Author(s): G. Terry Harris

Publication: Web Session

Volume:

Issue:

Appears on pages(s):

Keywords:

DOI:

Date: 12/14/2018

Abstract:
The 90-minute time limit has been in ASTM C94 since 1935, before any of us were involved with the concrete industry. There’s no clear reason for the inclusion of the 90-minute limit and yet the mention of removing it from the C94 document often creates lengthy discussions. Is it necessary? Does it have significant impact on concrete quality? How does it impact the ready mix producer? How does it impact the contractor?