00771110

Component

https://doi.org/10.3141/1668-06

http://scholar.google.com...Lane&publication_year=1999

Beginning in the late 1980s, the Virginia Department of Transportation (VDOT) observed that concrete made with aggregate containing microcrystalline, strained, or highly fractured quartz was failing earlier than expected due to alkali-silica reactions (ASR). These reactive constituents are widespread in the aggregate resources available for use in Virginia. Difficulties have been encountered in accurately classifying aggregates with regard to their potential reactivity. Consequently, VDOT instead is attempting to identify and use cementitious materials that prevent or hinder ASR. These materials, pozzolans and slag, have been shown to reduce both ASR and permeability, resulting in a more durable concrete. Two newly developed tests were used to evaluate the effects of cementitious materials (ASTM C1260 and ASTM C1293) on the ASR potential of construction aggregates. The results of these tests were compared with the results of a more accelerated test (ASTM C441) that uses an extremely reactive synthetic aggregate. Differences in test results were noted: the C441 test, using more stringent criteria, predicted higher replacement levels for a given pozzolan or slag with a portland cement of a given alkali content than are interpreted from the C1260 or the C1293 tests. However, although a greater degree of confidence in long-term performance can be placed in material levels that "pass" the C441 test, the material replacement levels that meet the criteria specified in the C1260 and C1293 tests have been generally observed to provide acceptable performance in the field.

This paper appears in Transportation Research Record No. 1668, Concrete in Pavements and Structures.

English

p. 42-47

1999

Transportation Research Record

0309070635

Figures (3) ; Photos (2) ; References (17) ; Tables (2)

Accelerated tests; Aggregate tests; Alkali silica reactions; Concrete; Durability; Pozzolan; Quartz; Slag; Test procedures

Virginia

Highways; Materials; I32: Concrete

TRIS, TRB, ATRI

Oct 7 1999 12:00AM

• BOND INTERACTION BETWEEN CONCRETE PAVEMENT AND LEAN CONCRETE BASE
• CONCRETE CAPILLARY POROSITY AS IT RELATES TO DURABILITY OF PAVEMENTS BUILT WITH ALKALI-SILICA-REACTIVE AGGREGATES
• CRACKING DAMAGE/DETERIORATION AND REHABILITATION CONSIDERATIONS OF SOME BIRMINGHAM, ALABAMA, INTERSTATE BRIDGE DECKS
• EFFECT OF MICROCRACKING ON DURABILITY OF HIGH-STRENGTH CONCRETE
• GEOCHEMICAL METHOD FOR IDENTIFYING ALKALI-SILICA-REACTION GEL
• IMPACT OF PROCESSED CELLULOSE FIBERS ON PORTLAND CEMENT CONCRETE PROPERTIES
• INFLUENCE OF ALKALINE EARTH SILICATE ADMIXTURE ON DURABILITY OF PENNSYLVANIA TURNPIKE BRIDGES
• INFLUENCE OF TOTAL AGGREGATE GRADATION ON FREEZE-THAW DURABILITY AND OTHER PERFORMANCE MEASURES OF PAVING CONCRETE
• INVESTIGATION OF DESIGN PARAMETERS AFFECTING TRANSVERSE CRACKING IN JOINTED CONCRETE PAVEMENTS
• MITIGATION OF ALKALI-SILICA REACTION IN PAVEMENT PATCH CONCRETE THAT INCORPORATES HIGHLY REACTIVE FINE AGGREGATE
• PROPOSED GUIDELINES FOR THE PREVENTION OF ALKALI-SILICA REACTION IN NEW CONCRETE STRUCTURES
• USE OF A LITHIUM-BEARING ADMIXTURE TO SUPPRESS EXPANSION IN CONCRETE DUE TO ALKALI-SILICA REACTION
• VERY-EARLY-STRENGTH LATEX-MODIFIED CONCRETE OVERLAY