Abstract:
WHETHER FROST IN LEAVING THE GROUND IN THE SPRING OF THE YEAR LEAVES BEHIND DAMAGING EFFECTS ON CONSTRUCTED ROADS IS A QUESTION THAT WAS DISCUSSED AT PRACTICALLY ALL MEETINGS OF REGIONAL AND NATIONAL MAINTENANCE ENGINEERS GROUPS FOR SEVERAL YEARS. THERE WAS A WIDE DIFFERENCE OF OPINION AS TO HOW MUCH THE ROADS WERE BEING WEAKENED, AND EVEN A GREATER DIFFERENCE OF OPINION AS TO HOW THE PROBLEM MIGHT BE SOLVED. THE OBJECTIVE OF THE PROJECT AS SET UP BY THE HIGHWAY RESEARCH BOARD IS TO SECURE BY FULL SCALE FIELD BEARING LOADS THE ACTUAL LOSS IN CARRYING CAPACITY BECAUSE OF FROST ACTION OF VARIOUS TYPES OF ROADS AND THE ELEMENTS THAT MAKE UP THE ROADWAY. IN ORDER TO GET DATA FROM AS MANY SOURCES AS POSSIBLE, NINE STATES HAVE BEEN ASKED TO JOIN IN THE RESEARCH PROJECT. DEFINITE PROCEDURES HAVE BEEN OUTLINED SO THAT THE DATA SECURED MAY BE COMPARABLE. FULL SCALE LOADS ARE TO BE APPLIED TO CERTAIN PREDETERMINED POINTS OR LIMITED AREAS BEGINNING AS SOON AS THE FROST STARTS LEAVING THE GROUND, AND REPEATED AT FREQUENT TIME INTERVALS DURING THE THAWING PERIOD, AND AT SUITABLE INTERVALS DURING THE REST OF THE SEASON, IN ORDER THAT THE COMPARATIVE CARRYING CAPACITIES OF THESE ROADS CAN BE DETERMINED. SO FAR THE LIMITED TESTS THAT HAVE BEEN MADE DISCLOSE A VERY DEFINITE PATTERN OF RAPID ROAD WEAKENING, UP TO 60 PERCENT LOSS WHILE THE FROST IS LEAVING THE GROUND AND THEREAFTER GRADUAL RECOVERY. /AUTHOR/
Supplemental Notes:
Vol28, Pp273-281, 13FIG, 1TAB. 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.
