00755030

Component

https://doi.org/10.3141/1630-10

http://scholar.google.com...NSON&publication_year=1998

The thermal stress restrained specimen test (TSRST) was used to evaluate the low-temperature cracking resistance and aging performance of modified asphalt concrete (AC) specimens. One aggregate, two asphalt cements (AAA-1 and AAB-1), five modifiers (latex polymer, ethylene acrylate copolymer, rubber powder, elastomer, and a blend of polypropylene and Kevlar fibers), and four 85 deg C oven aging levels (0, 5, 25, and 50 days) were considered. The results of the bending beam rheometer test (BBRT) on binders at -20 deg C showed that AAA-1 displayed a smaller creep stiffness than AAB-1. Only two modifiers increased the deflection and softness of AAB-1. The additives in AAA-1 did not improve its low-temperature rheological behavior. These results served as the basis for comparison with those from the TSRST. The fracture strength and temperature of AC specimens are sensitive to asphalt type (4.11 MPa and -32.2 deg C for AAA-1, 3.28 MPa and -25.4 deg C for AAB-1) and degree of aging (from 4.11 to 2.04 MPa and from -32.2 to -21.2 deg C for AAA-1 for aging levels from 0 to 50 days at 85 deg C). Only one modifier in AAB-1 (among the two candidates identified with the BBRT) improved the low-temperature performance of the AC specimens. After 50 days of aging, no improvement was observed. The modified AAA-1 AC specimens displayed an optimum improvement in performance for aging levels of 25 and 50 days. Several modified AC specimens displayed a low-temperature failure without apparent fracture. This behavior would appear to be advantageous for the performance of pavements in cold regions.

This paper appears in Transportation Research Record No. 1630, Asphalt Mixtures: Stiffness Characterization, Variables, and Performance.

English

p. 77-86

1998

Transportation Research Record

0309065011

Figures (10) ; Photos (2) ; References (6) ; Tables (2)

Aging (Materials); Asphalt cement; Asphalt concrete; Creep; Fracture mechanics; Laboratory tests; Low temperature; Rheometers; Specimens; Stiffness; Thermal stresses

Modifiers

Highways; Materials; I31: Bituminous Binders and Materials

TRIS, TRB, ATRI

Oct 12 1998 12:00AM

• APPLICABILITY OF SUPERPAVE TO MODIFIED ASPHALTS: A MIXTURE STUDY
• AUTOMATED PROCEDURE FOR GENERATION OF CREEP COMPLIANCE MASTER CURVE FOR ASPHALT MIXTURES
• CALCULATING AIR VOIDS AT SPECIFIED NUMBER OF GYRATIONS IN SUPERPAVE GYRATORY COMPACTOR
• CORRELATION OF SUPERPAVE G*/SIN DELTA WITH RUTTING TEST RESULTS FROM ACCELERATED LOADING FACILITY
• DETERMINING GYRATORY COMPACTION CHARACTERISTICS USING SERVOPAC GYRATORY COMPACTOR
• EFFECT OF AGGREGATE GRADATION ON FATIGUE LIFE OF ASPHALT CONCRETE MIXES
• EFFECTS OF AGING ON VISCOELASTIC PROPERTIES OF ASPHALT-AGGREGATE MIXTURES
• EVALUATION OF ABILITY OF SUPERPAVE SHEAR TESTER TO DIFFERENTIATE BETWEEN MIXTURES WITH DIFFERENT AGGREGATE SIZES
• EVALUATION OF STRIPPING FOR ASPHALT CONCRETE MIXTURES USING ACCELERATED TESTING METHODS
• IDENTIFICATION OF MOISTURE-SUSCEPTIBLE ASPHALT CONCRETE MIXES USING MODIFIED ENVIRONMENTAL CONDITIONING SYSTEM
• REFERENCE STANDARDS FOR USE WITH INDIRECT TENSION TEST
• RELATIONSHIPS AMONG RATE-DEPENDENT STIFFNESSES OF ASPHALT CONCRETE USING LABORATORY AND FIELD TEST METHODS
• SHORT-LOADING-TIME STIFFNESS FROM CREEP, RESILIENT MODULUS, AND STRENGTH TESTS USING SUPERPAVE INDIRECT TENSION TEST