00210958

Component

http://onlinepubs.trb.org...rbbulletin/270/270-001.pdf

THE RESULTS OF COMPREHENSIVE LABORATORY TESTS ON ASPHALT PAVING MIXTURES WITH CHRYSOTILE ASBESTOS ARE DESCRIBED. THE MAIN EFFECT OF THE FIBER APPEARS TO BE ON PLASTIC STRENGTH AS MEASURED BY STATIC LOAD TESTS. STATIC TENSILE STRENGTH OF THE CONTROL MIX WAS INCREASED AS MUCH AS 20 TIMES AT STANDARD ASPHALT CONTENTS BY ADDING 3 PERCENT 7M FIBER. SIMILAR INCREASES IN STATIC COMPRESSION STRENGTH WERE SHOWN AT ASPHALT CONTENTS HIGHER THAN NORMAL. STATIC COMPRESSION TEST DATA SUGGEST THAT A WIDE RANGE OF FLEXIBILITY CHARACTERISTICS MIGHT BE ATTAINABLE BY ADDING ASBESTOS, AS A WIDE RANGE OF ASPHALT CONTENT APPEARS TO BE PERMITTED. SAMPLES OF ASPHALTIC CONCRETE REMOVED FROM PAVEMENT MIXES PLACED FOR SERVICE EVALUATION SUSTAINED A 510-PSI CONCENTRATED COMPRESSION LOAD FOR 1 HR AT 140 F WITHOUT FAILURE IN LABORATORY TESTS. LABORATORY TEST RESULTS ON CONTROL MIXES SUGGEST THAT USE OF A DYNAMIC TENSION (COHESION) TEST AT 140 F FOR MEASURING RESISTANCE TO PLASTIC DEFORMATION IN MIX DESIGN IS JUSTIFIED. HOWEVER, FOR PAVEMENT MIXES WITH ASBESTOS INCLUDED, DYNAMIC TESTS AT 140 F DO NOT APPEAR TO BE ADEQUATE FOR MEASUREMENT OF RESISTANCE TO PLASTIC DEFORMATION. SIGNIFICANT INCREASES IN DYNAMIC TENSILE STRENGTH AND REPEATED BLOW IMPACT STRENGTH AT 0 F WERE ALSO EVIDENT WHEN SHORT ASBESTOS FIBERS WERE INCLUDED IN PAVEMENT MIXES. THE ABILITY OF SHORT CHRYSOTILE FIBERS TO PREVENT CRACKING IN THIN FILMS OF ASPHALT-FILLER MIXES DURING ACCELERATED WEATHERING TESTS IS DESCRIBED. /AUTHOR/

No 270, pp 1-19, 8 FIG, 3 TAB, 5 PHOT, 7 REF, 4 APP Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01410655

19p

1960

Highway Research Board Bulletin

Digital/other

Accelerated weathering; Asbestos; Asphalt concrete; Asphalt content; Asphalt pavements; Asphalt tests; Bituminous mixtures; Cohesion; Compressive strength; Fillers (Materials); Flexibility; Laboratory tests; Load tests; Mix design; Pavement cracking; Plasticity; Prevention; Shock resistance; Static loads; Tensile strength; Thin films

Impact strength

Highways; Materials; Security and Emergencies

TRIS, TRB

Jun 3 1994 12:00AM

• Design and Construction of Epoxy Asphalt Concrete Pavements
• DETERMINATION OF AGE HARDENING TENDENCIES AND WATER SUSCEPTIBILITY OF PAVING ASPHALT BY THE SONIC METHOD
• RHEOLOGY OF BITUMENS AND THE PARALLEL PLATE MICROVISCOMETER