| Show TEST GOOD ROAD MATERIALS much detailed technical information secured in experiments by public roads bureau tile the bureau of it Is believed that public roads united states slates department its testing through m ent of agriculture division has d done one more than any other single agency in develop developing ng the intelligent use of bi in road construct construction lon for example experiments conducted under service con 1 whether decided bureau dictions by this could be used in e Q r a soft stone ston bituminous maccad macadam am and bituminous concrete whether rocks having a marked d cleavage a ge could be used to adi trantle cleav construction construct lor what iffe g e in s uch such quantities of bitumen give the alie best result nhen hen used as surface treatments on water bound bacad macadam am and whit what kind of covering material and wh what at quantities should be used in any case A large amount of detailed te technical clint information valuable to highway engineers generally has been secured by the bureau in the course of its research and experimental work the ability of the highway engineer to construct roads which would accommodate automobile traffic lins hns in no ermall degree been the underlying reason that the automobile industry has developed to its present enormous proportions in 1910 1916 the passage of the federal aid road act marked a new ep epoch och in highway construction in the united states the war then in progress emphasized pha sized the need of further developments in road the alip burp nu ja vi c ext 5 w A S r i 3 bituminous macadam mixing method lias has sought to keep well to the front in the solution of the he new problems presented and is today conducting experiments peri perl ments and investigations of a fundamental character |
