Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1920-05-04

and poor drainage conditions and there
can be no doubt that q pavement from
which could be cut cubes of solid con,
fourteen inches thick" as described by
Mr. Mccain. would be infinitely better
Tor the purpose were It not for the
fact that tho thickness mentioned is
Just about double that which is COM
monty used and that tho cost OF such
road would be prohibitive. -
II is not however proper TO draw
the conclusion that the old macadam
roads can serve no useful purpose
SrRIy because of the failure OF Wits
treatments Of various bituminous ma
terials, they are frequently tranSformco
70 such degree that the travelling pup
llc does not recognize that they are
riding on road of macadam type, and
in countless instances they are still TO
be found successfully carrying largo
volumes OF traffic. even though this may
be less severe than the traffic on the
Lincoln highway. Their value as "A
foundation for asphalt and other types
OF pavement has been generally admitted,
and their use for this purpose has re-
suited in tho saving of large sums OF
money when the work was performed
under proper restrictions and super
vision.
As q single instance familiar. 10
Philadelphians, City line avenue from
Overbrook almost 20 the Schuylkjll
river Is an old macadam road, different
portions OF which were surfaced at
various times between 1919 and 1914
with sections of aRphaltic pavements 8
which have since been carrying large
volumes of traffic with entire satisfaC-
ton. A disregard OF the fact that many
OF these old roads had been worn quite
thin by traffic before being used for
the toundat lon. and an enthusiastic. but
misguided belief on the part of ocCa =
siona road builders that btuminous
trpAtmnntl .,
could be laid successfully in the absence
OF substantial foundation have been
the cause OF most of the failures in this
type of construction.
A further point bearing on tho matter
is the fact that today engineering
organizations in designing and building
entirely now pavements viii usually pay
close attention 20 drainage problems
| ana make proper provisions for this
purpose whereas most of these Old
macadam roads date back 10 the period
when a hard surface was considered tho
! chief essential for an improved road,
| and little or no attention was given 10
drainage matters and still less money
| expended for that purpose IN the con.
| struction OF the road. II would there.
! fore seem that when these old roads
| are to be utilized as foundations for neY
| pavements, they should receive at leas,
as much attention in regard to keeping
| wafer away and thus preserving dry
surface beneath them az tho newer and
| stronger. structures which are beinp
built today.
To summarize the above. it seems fail
TO conclude that in road building, iusI
! as in any other pursuit. tho use Of q
single key In the hope of opening the
door to SUCCESS, or tho following OF 8
single formula regardless of all the
| variety or conditions to be met and
| overcome. must in the long run prov,
to be incorrect. The laying down Of
the broad rule that 3, fyive, tyno rt
! road has no value in any locality be,
cause of it's failure in most dense is
populated localities TO which IL is
no longer suited. would inevitably mean
the loss or a vast sum Of money pre-.
! viously invested in the construction o,
| these roads, not to mention the very
| considerable amount which would bt
! required for the mere purpose of dig.
| ging them up and hauling them away.
| The original cost of these olt