Please use this identifier to cite or link to this item:
|Title:||Performance of concretes proportioned with Pyrament blended cement|
|Authors:||Pyrament/Lone Star Industries, Inc.|
Construction Productivity Advancement Research Program (U.S.)
Husbands, Tony B.
Malone, P. G.
Wakeley, Lillian D.
Blended hydraulic cement
Rapid chloride permeability
|Publisher:||Structures Laboratory (U.S.)|
Engineer Research and Development Center (U.S.)
Abstract: Pyrament Blended Cement (PBC) is known in the construction industry for its ability to gain strength rapidly and achieve very high early strength. The Waterways Experiment Station (WES) conducted a laboratory evaluation of concretes made with PBC to determine if these concretes perform better than concretes made with ordinary portland cement (OPC) in tests of various aspects of concrete durability. For this study, six concretes based on PBC-XT were proportioned with three cement contents and two aggregate types. The objective was to determine if the cement, advertised as giving high early strength and marketed initially as a rapid-construction material, is durable enough to justify its use for long-term performance in addition to shorter construction time. Concretes prepared from PBC-XT cement were subjected to analyses of its resistance to damage during cycles of freezing and thawing, expansion in a high-sulfate environment, damage from underwater abrasion, penetration of dissolved chlorides, scaling from deicing chemicals, and expansion from chemical interaction between alkalies in the cement and silica in aggregate. In all categories, the PBC-XT cement concretes achieved or exceeded expected performance based on the manufacturer's product literature. In all but the last category, PBC-XT concretes performed better than is generally expected of high-quality OPC concretes. As an example of superior performance, PBC-XT concretes made with seven sacks of cement per cubic yard and limestone aggregate were tested to 500 cycles of freezing and thawing according to ASTM C 666, through which they retained >90 percent of their initial dynamic modulus. Also, samples tested for sulfate expansion gave values consistently below the ASTM C 595 limit of 0.1 percent after 180 days. In tests of rapid chloride permeability (AASHTO T 277), PBC-XT concrete samples tested as early as 7 days after casting achieved *low* permeability ratings (<1,000 coulombs). Values for year-old specimens averaged a remarkable 100 coulombs. Other aspects of performance investigated included: effects of various temperatures and water-cement ratios on workability, time of setting, and rate of strength gain; bonding to existing concrete; drying shrinkage; creep under sustained load; and effects of different storage conditions.
|Rights:||Approved for public release; distribution is unlimited.|
|Appears in Collections:||Technical Report|
Files in This Item:
|TR-CPAR-SL-94-2.pdf||16.27 MB||Adobe PDF|