Deseret evening news. [volume] (Great Salt Lake City [Utah]) 1867-1920, 1910-01-27
Building" Prof. Beckstrand said:

cnarSe OF the design and construction
u any road to prepare suitable ma
| - inl LOT the surface of the road and
10 see that the material is properly
piaced in position It is the purpose
| tlIs paper to briefly discuss the
| iiportant properties that stone should
possess that Will make 1t desirable
rIs e.ai lot the wearing surface OF
tS In nearly every case,
the country roads. Including the sub
urban. and the interurban roads as
wen as many village streets and city
uee.s, VIII be covered with gravel or
| ha.eo with macadam- The use of tho
letter paving material such as con-
800. asphalt, brick, and wood blocks
| ~ ~ paving viii be confined mainly to
| T, nc more important city streets.
! therefore VIC will discuss in this pa per
oniy gravel and broken stone for use
on country roads
INC amount OF improvement of roads
! win Win tne resulting costs will. as n
@ au,e DC IN proportion to the amount
"'u Vaiue OF the traffic which the road
carries. However, in the improycmept
/ OF any road. the foundation must he
ns os enough to properly distribute
oNer enough area of ground, so as
~ 70 make permanent depression,
,ne heaviest concentrated load that the
wagon can carry and the
h,,i,. team can pull. And so roads
alstricts must be strong enomrli
20 carry the occasional heavy
load, For the purpose of dis,
LESSON therefore. we can divide roads
INTO at least two divisions. first main
s sstunk INES carrying great amount of
Sy ans tratnc' as we'll as light vehicles
ana automobiles: second. countr,,
roads. situated in a fairly popnlon.
district In general there would be re-
Iuireo the best material to be had In
nc construction OF the trunk linz or
,ne ihterurban road. while material or
Iesser cost and dura biIity would he eco
noinical and properly used in building
tic ROAD carrying the lesser traffic.
UNDER ENGINEERING LAWS
Road building then is subject to the
,s,e en6ineerlng laws of economies az
bridge building. where the structure 10
made of the proper material which,
aiso' must be properly distributed so
.iia. oVerStraining will not result 1t
IS therefore evident that good knoUl-
eoge CT the properties of the material
from which we may choose to build
must be had. The amount of wear stone
VIII yield to. the amount of impact II
can resist without breaking how the
stone VIII resist the disintegrating In
nucnces of the atmosphere, how the
sion Will recement and remain on the
road holding other stone in place. and
not exposing them and not forming an
undesirable mud, these are the things
we must know about all the rock In tho
vicinity which are available for use A
kind of geologic map of the state show
Ing the location of available stone. and
giving the useful information about
each quarry and kind of stone. would
iYNa TO L.
would be useful to us ALL
The use OF gravel on roads needs but
little discussion. The large varieties of
gravel are not equally good for road
building. some will pack well on the
surface, while others will not Gravel
is an accumulation of stone varying
in size from sand up TO the size of ones
fist. II the sizes are properly
proportioned. there will be just
enough fine material to fill the
voids of the coarser There should
De enough OF the proper Kind
of clay to cement the grains and hold
them in place. Too much clay softens
allowing the mass to soften in wet
weather, forming n mud. Large stones
tend to work to the surface making
the road uneven. The largest size
gravel for roads. as given by Prof
Baker, is from inch to y inch for the
largest size, and then grading down to
sand, Gravel usually has sufficient
strength to carry heavy loads. 1t being
the hard material which has resisted
the wear of the water for an indefinite
period of time. Gravel does not make
a good foundation for q road, neither
does 1t make n good wearing surface
as compared with broken stone, and SO
1t will naturally be used only on cheap
er construction.
USE OF GRAVEL
Gravel Is widely distributed in the
state. The old ancient lake Bonneville
with the numerous streams that flowed
into 1t, have piled up great deltas OF
gravel and sand in the valleys and
widely distributed the same over the
state.
In the country districts, most any of
the gravel beds which are found there,
II properly spread upon the road will
greatly improve 1t, especially II the
earthwork is properly graded before
hand
main trunk roads leading into cities
from the country. and leading from
one city to another will be covered
with and surfaced with broken stone
OF different sizes. and of q thickness
sufficient to carry the traffic. Such
road construction is usually called
macadam pavement, 1t is the behavior
of this broken stone. when placed
on the road, under the influence of
the weather. and of the different
kinds of vehicles passing over it. that
we wish to discuss.
The effect OF the atmospheric air
and water on all rock Is to dlsinte-
CRATE It Different kinds of rock break
down moro or less rapidly depending
on the composition of the rock, its
chemical constitution. Its hardness, its
porosity and on the reactions that
occur between the stone composition
and acids contained in atmospheric
waters 1t Is essential that water be
not allowed to percolate down into the
| compact stone Water freezing creates
| n great expansive force and will loosen
| the foundation layers permitting the
| road to ravel Water is absorbed by
| the stone and there freezing tends
| to break II down. II the earth founda-
| ton on which the stone rests becomes
| wet ii softens and the stone is al
| lowed to become displaced. The top
| LAYER should then be impervious to
water Numerous freezing and thawing
| tests have been made at the University
| of Utah on different kinds OF stone.
| and brick. for the purpose OF obscrv-
| inr the effect OF frost on them. With
| n limited number OF freeZings such
| 40 could be made in n series OF
| tests many of the samples were
| broken down almost 10 mud. an1 the
| effect of frost Is easily observed on
| all kinds Some split. other break In
/ snalls others dissolve In spots.