Note: Descriptions are shown in the official language in which they were submitted.
i BACKGROUNI~ OF THE INVENTIO~l
I Field of the Invention.
I ~
The present invention ;s related to civil structures such
! as a road for use in cold clima~es, as well as a machine and
¦ technique for constructing same. More particularly, the present
invention is directed towards a method and apparatus for con-
, structing a novel road whose principal component consists of a
I crushed ice aggregate.
¦' Description of the Prior Art-
¦I Wintertime work in environmentally sensitive parts of the~l arctic and sub-arctic often requires that access roads, work
li pads and air strips be constructed of non-permanent materials
¦I which will not be detrimental to the underlying native
Il vegetation~
¦~ The prior art has recognized the unique problems
!, surrounding the construction of a suitable roadway in such
cold climates. In the past, a common solution has been to
! construct such roads of ice. For example, the Rowley et al
I¦ patent t3,986,783) teaches a method and machine for construct-
20 1¦ ing ice roads upon snow-covered regions. The machine gathers
snow from the region upon which the road is to be built, heats
! the gathered snow until it is partially melted and becomes
¦ slush, and then spreads the slush to form the road upon re-
1, freez;ng. Other United States Patents of which I am aware
I which also relate to ice roads formed from snow include the
Nikolaev et al patent (3,371,586) and the Condo et al ~atent
(3,818,711).
However, contrary to pop~lar opinion, in many parts of
the high latitudes very little snow falls, and what does fall
li is not predictable and seldom remains in a uniform distri-
¦~ b~tion over the land surface because of incessant transport by
!i
I -3- ~
!l
the wind~ As a consequence7 snow is often found to be an
unreliable material of construction thereEore severely l;miting
the known prior art techniques of utilizing snow to construct
¦ ice roads.
~ In contrast, the occurrence of sub-freezing temperatures
¦ and consequent freezing of ~he surfaces of lakes and rivers is
¦ highly predictable and is uniform over large regions. Ice
therefore appears to be a more readily available base material
from which roadways in cold climates can be constructed. Of
I course, i~ would be necessary to mine or harvest the ice pre-
paratory to constructing the desired road. Fortunately, the
technology of mining or harvesting ice was developed years agv
when such ice was the primary source o refrigeration during
warmer periods of the year. However, to the best uf my know-
ledge, the use of such ice as a construction material forwintertime temporary structures suc.h as roads or the like has,
prior to my invention, not been util;zed.
In a publication entitled: "Building And Operating Winter
Roads In Canada And Alaska" by Kenneth M. Adam on behalf of
the Canadian Department of Indian and Northern Affairs, (be-
lieved published in 1978~, the author describes an aggregate
ice road whose "development was inspired by Alaskan Arctic Gas
¦ Pipeline Company as a technique to protect sensitive terrain
from heavy traffic in areas where a lack of snow or lack of
available water precludes the use of snow roads or sol~d ice
roads." (Page 59). The aggregate ice road described by this
author is believed derived from earlier studies and experiments
I had performed in Fairbanks, Alaska, on behalf of the Alaskan
Arctic Gas Pipeline Company. The author in this publication
describes an aggregate ice road constructed utilizing a
¦ medium-sized tractor to pull the aggregating machine, a front-
end loader, several dump trucks, a medium sized crawler tractor
with blade for shaping the road, and a water tanker truck wî~h
I spray bar for binding the aggregate. The techn;que and
' apparatus therein described calls for mining the aggregate
~l using a roto~tiller and then transporting the ice aggregate by
j front end loaders and dump trucks to the site. The loaded
¦ trucks dump the aggregate directly on the site, whereafter the
j crawler tractor shapes the road ~o the desired width and thic~-
I ness. Water trucks are then used to finish the road by
! sprinkling with one inch of water. The author concludes that:
"After sprinkling, several hours should elapse before heavy or
I large numbers of vehicles are allowed OD the road. This will
¦ allow time for the bonds between aggregate particles to freeze
I solidly before the road is opened to traffic." (Page 6I).
I While the foregoing article hy Mr. Adam summarizes my
¦ earlier experimental work as of around March, 1977, the state
of the art at tbat time was replete with several major disad-
vantages. Initially, the several large pieces of difEerent
~ ! equipments required to build the road did not lend the techni-
¦ que to rapid or efficient construction. Further, my field
¦ tests conducted in Fairbanks did not encompass all of tbe
¦ conditions likely to be encountered in the higb latitudes,
¦ and, consequently, left many questions unanswered. For example,¦
the test sections had been placed over a relatively smooth~
hard subswrface. Also, although the test sections constructed
during the field test had successfully withstood severe heavy
equipment loading, such loading was not done until several hours
had elapsed from the time of spraying. Finally, the field
--5--
Il,
j tests at Fairbanks had been conducted with ambient temperatures
¦ above 0F9 and no ac~ual field experience was obtained at
lower temperatures (e~g., -20 to -40F).
I Since the initial series of tests described above7 I have
5 1l further refined my techn;que for constructing an ice aggregate
j road in extremely cold (e.g.~ below -45F) temperatures9 and
, have developed an apparatus which is uniquely designed to
j construct a smooth ice aggregate surface over uneven terrain
¦l and which permits near immediate use of the finished surface.
!! It is towards this end that the present invention is advanced.
I'
OBJECTS AND SUMMARY OF THE I_VENTION
It is thereore a primar-y object of the present invention
to provid~ an ice aggregate structure, such as a road, and a
method and appara~us for constructing same~ which OVerCQmeS
lS the deficiencies noted above with respect to the prior art.
Another object of the present invention is to provide a
pr~ctical technique for constructing an ice aggregate road in
¦ high latitudes where temperatures are encountered below -45F.
A further object vf the present invention is to provide a
~0 ¦I method of constructing an ice aggregate road which provides
sufficient strength ~or heavy equipment loading within minutcs
after construction.
¦ An additional object of the present invention is to provide
¦ a novel and unique machine for placing, grading and bonding
~S ¦! ice aggregate to the route desired for a roadway which is
self-contained and self-su-ficient and which is capable of
operating from the surface over which it is constructing.
, A still further object of the present invention is tc
1, provide an ice aggregate placement and bonding machine which
!l
Il -6-
is designed to construct a smooth ice aggregate surface over
uneven terrain, which may change grade as required, and which
can bank road curves as necessary~
Another general object of the present invention is to
provide a crushed ice distributing and bonding machine for
i constructing, on a continuous basis, roads and other civil
! structures over natural, perhaps uneven, terrain without any
machinery contact with the terrain.
I The foregoing and other objects are attained in accordance
I with one aspect of the present invention through the provision
of a method of building a road suitable for use in cold cli-
! mate, comprising the steps of crushing ice to form an ice
I aggregate, removing most of the ice particles from the aggre-
¦ gate which are smaller than a particular si2e, placing the
resulting ;ce aggregate over the route desired for the road,
and then bonding the upper portion of the placed ice aggregate~
The bonding step includes the step of spraying water onto the
top surface of the placed ice ag~regate. The bond water is
preferably heated. The method further contemplates the step
of preventing evaporative cooling of the heated spray water by
substantially enclosing the area between the source of the
i heated spray water and the top surface of the placed ice aggre-
gate. The source of spray water may be passed over the top
surface of the placed ice aggregate in a single pass or iD
multiple passes.
In accordance with another aspect of the present invention7
there is provided apparatus ~or constructing an ice aggregate
road, which comprises means adapted to receive ice aggregate
for distributin_ it over a portion of the route desired for
-7-
.
¦ the road, and means operatively coupled to the distributing
¦ means for applying bond water to the top surface of the distri-
buted ice aggregate. Means are also provided for supporting
I the ice aggrega~e distributing means and the bond water apply-
I ing means for reciprocal movement over the portion of the roadbeing formed. Meàns are also operatively coupled to the
t supporting means for transporting same from one portion of the
road to the next adjacent portion upon completion of construc-
tion of the first portion of the ice aggregate road. The
1, transporting means is adapted for movement over that portion
¦ of the ice aggregate road just completed.
In accordance with another aspect of the present invention~
j means are preferably provided for selectively controlling the
I transverse angle of inclination of the supporting means with
¦ respect to the portion of the road under construction whereby
such portion may be constructed with a bank. Means may also
I be provided for interconnecting the supporting means and the
¦ transporting means for selectively raising and lowering the
supporting means.
¦ In accordance with more specific aspects of the present
invention, the transporting means may include first and second
wheeled carriages or modules whicb are respectively positioned
adjacent each end of the supporting means and which are inter-
connected by a transverse frame member. The space between the
25 I first and second wheeled carriages is adapted to receive means;
such as a dump truck, for providing the ice aggregate to the
distributing means. The first and second wheeled carriages
Il more particu~arly include means for housing an operator of the
¦l apparatus, means for containing the bond water, means for
Il ~8-
1 . ~
Ii .
, 3L~
i
I pumping the bond water to the bond water a2plying means,
¦¦ means for heating the bond water and means for providing
, tranSport power.
ll In accordance with other specific aspects of the present
S ! invent;on, the distributing means comprises hopper means includ-
ing side walls, an open top for receiving, an open bottom for
¦ distributing and a rear wall for grading the ice aggregate
over the port;on of the road being constructed. The bond
I water applying means is preferably positioned rearwardly of
I and adjacent to the rear wall of the hopper means. ThP bond
water applying means more particularly may include a plurality
! of spray nozzles connected to a common source of bond water
¦ and po.sitioned in a spaced relationship to the top surface of
~ the distributed portion of the ice aggregate. Means are also
1~ ! included for providing a substantially vapor saturated region
between the spray nozzles and the top surface of the ice
aggregate, such means preferably comprising means for substan-
~ tially enclosing the area between the spray nozzles and the
¦ top surface of the ice aggregate for preventing evaporative
I cooling of the bond water, such enclosing means preferablyincluding a flexible skirt.
j In accordance with more specific aspects of the present
invention, the bond water applying means further includes a
¦ source of bond water, a supply pipe for delivering bond water
¦ to the sprày nozzles from the source, a return pipe co~nected
¦ to the supply pipe for returning unsprayed bond water back to
i the source, ar-d means for causing continuous circulation of
the bond water through the source, the supply pipe and the
return pipe to prevent freezing of the bond water. The spray
I nozzles each preferably include spring-loaded check valve ~eans
Il _ g _
~ 5~
for preventing spraying of the bond water therefrom until the
pressure in the supply pipe exceeds a predetermined contr~
able amount. The spray nozzles are preferably arranged
substantially linearly across the rear edge of the distributing
S means.
In accordance with yet another aspect of the present
invention, there is provided a method of constructing an ice
aggregate road in cold climates using a machine that supports,
transports, distributes and grades the ice aggregate and bond
water, comprising the steps of positioning the machine adja-
cer2t a first area over which the road is desired to be form2d~
distributing and grading ice particles over the first area
with the machine, applying bond water to the top surface of
the ice particles in the first area with the machine, moving
the machine onto the bonded ice particles in tbe first area
~which may be performed immediately following the preceding
step), and repeating the preceding steps for a second area
adjacent the first area.
In accordance with yet another aspect of the present
invention, there is provided a roadway for cold climates which
comprises an ice aggregate from which substantially all ice
particles smaller than a predetermined size have been removed,
and a bonding layer formed in the upper portion of the ice
aggregate. The bonding layer comprises an ice layer formed by
applying bond water to the upper portion of the ice ag~regate,
while the predetermined size of ice particles is approximately
0.1 inch in cliameter. The thickness of the bondin~ layer is
dictated by required structural strength, and will be generally
in the range of 6-12 inches.
Il .
Il -10
BRIEF DESCRIPTION OF THE DRAWINGS
_. ..
Various objects, featur~s and attendant advantages o the
present invention will be more fully appreciated as the same .
I becomes better understood from the following detailed descrip
I tion of the present invention when considered in connection
¦ with the accompanying drawings, in which:
¦ Figure 1 ;s a side view in elevation illustratin~ a
preferred embodiment of the apparatus for constructing an ;ce
aggregate road in accordance with the present invention;
10 ~ Figureg 23 3 and 4 are sectional views illustrating
various portions of the preferred embodiment illus~rated in
Figure l;
Figure 5 is a top view of the preferred embodiment
~ of the machine of Figure l;
Figure 6 i5 a partial, longitudinal sectional view
of the preferred embodiment illustrated in Figure 5;
Figure 7 is an end view which schematically ilius-
trates the placement of the spray bar assembly over the ice
I ag~regate road in accordance with the present invention;
¦ Figure 8 is an enlarged, sectional view illustrating
¦ a portion of the spray bar assembly of the present invention;
~igures 9 and 10 are schematic illustrations of the
I wheeled support modules or carriages of the machine of Figures
¦ 1 and 5; and5 I Figure 11 is a diagramatic view illustrating the
pray bar assembly and control components associated tberewith.
¦ DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
¦ Method
The technigue of the present invention may be summarized
I as follows. Initially, ice must be mined or harvested from.
I any convenient source, such as lake iceO The ice may be
harvested by any conventional equipment, such as a bulldozer.
I The ice is then crushed to a reasonably uniform gradation
¦ having particles with a maximum size of, for example, three to
¦ four inches in diameter. Commercially available ice crushers
li or breakers may be employed for this purpose, such as Model
¦1 60-300 manufactured by the Lilly Company of Memphis~ Tennessee.
¦I The preceding two steps may be combined by an in-situ ice
¦I' crushing step that combines both the harvesting and crushing
Il processes. This may be achieved, for example, by a roto-tiller
15 ¦¦ type of device.
The next step in the technique of the present invention
is to remove from the crushed ;ce aggregate subs~antially all
of the "fines", i.e., ice particles smaller than approximately
0.1 inch. The "fines" removal may be achieved by screening
the crushed ice by the use of, for example, flat deck screens
or sieves, a rotary drum screener, or the like. Although the
theory underlying the importance of removing the fines rom
the crushed ice aggregate is not fully understood, I have
discovered that, for a given ambient temperature, if the per-
~ centage of ice particles measuring 0.1 inch in diamete~ and
less of the gradation exceeds a certain value, it is not possi-
ble ùnder any conditions to construct a bond layer of sufficient
strength in high latitude climates for wheeled e~uipment
ut;lization. Inasmuch as specified fines control would be
I
- 1 2 -
i, .
difficult~ if not impossible, under field conditions, the
technique of the present invention employs an ice aggregate
! from which substantially all fines have been removed.
¦ Having removed the fines~ the resultant ice aggre~ate is
¦ then transpor~ed by any conventional means ~e.g. 7 truck, belt
¦ conveyor, auger~ to the site desired for the road o~ other
structure In this step, however, the fragile nature and
tendency to segregate of the crushed ice must be takeD into
I account, and ~herefore pneumatic conveying, slinging or the
I like, of the crushed ice aggregate should be avoided.
¦1 The next step in the technique of the present invention
is to place the resulting ice aggregate to the desired grade
without surface work or compaction. A preferred embodiment of
I a machine to perform this step will be described in greater
15 , detail hereinafter.
¦ The crushed ice aggregate, having been placed to the
desired grade, is then bonded in its upper thickness by spray-
ing, in either a single pass or in multiple passes, its free
surface with preferably heated bond water. The bond water is
preferably emitted from spray nozzles contained within an
! enclosure that effectively seals the space between the nozzles
! and the crushed ice surface to contain the spray water within
~ a vapor saturated region. Without such an enclosure, I have
¦ found that, at sub-zero temperatures, the ice aggregate, having
¦ had all fines removed, may be sealed from penetration by the
~ bond water This was believed due to evaporation of ~he bond
¦ water in transit from the spray nozzles to the ice aggregate,
and possibly from the ice aggregate surface itself, such eva-
1l poration being sofficient to cause subcooling of the bond
'I -13-
I
3L~
I water resulting in the formation of a surface ice sheet that
¦ undesirably sealed ~he ice aggregate surface from further
I penetration by the bond water. The enclosure~ according to
I the present invention, prevents evaporative cooling of the
' spray water prior to its contact with the crushed ice surface
¦ and provides a near 32F environment.
¦ At ice temperatures near and colder than 0F, the bond
¦ water is also preferably heated to a temperature inversely
l proportional to that of the crushed ice. Experimental results
j presently indicate that, for example, at -20E` a 12 inch thick
,I bond layer of considerable strength can be obtained with a
il bond water temperature of about 100F and a bond water quantity
on the order of 2.5 pounds per square foot. It has been found
~ that an interrelationship exists between bond water temperature
¦ and bond water quantity for a ~iven strength, with a reduction
: j in bond water quantity required as bond water temperature is
¦ incre.ased, and vicè-versa.
Experimental work hss produced ice aggregate roads with
I thicknesses as great as 3 feet and having a 6-8 inch thick
I bond layer. Road sections of greater or lesser thicknesses
may be constructed with the present invention, as may be desir-
! ed for particular loading conditions or terrain variations.
Normal wheeled traffic may traverse the bonded crushed
ice aggregate within seconds of the final spray pass. This is
extremely important in that under certain condit;ons 1~ the
arctic, environmental considerations do not permit traffic
over unprotected tundra; hence, a road building system that
~ can be constructed from itself, i.e., essentially "unrolledl'
:.~ . I
, across the desired route, ;s extremely desirable.
.`~ i
~ -14-
.~ .
558
¦ Apparatus
I The apparatus of the present invention is designed in
¦ particular to construct a smooth surface of crushed ice over
uneven terrain. The properties of crushed ice, e.g., low
density, lack of abrasiveness, flowability, low coeficient of
friction and shallow angle of repose, are all taken into
account in the preferred embodiment. The machine ;s designed
to operate from the surface tha~ it constructs; that i5, after
¦ constructing one section of ice ag~regate road, the machine is
! advanced over the completed section to construct the next
adjacent section, never coming into actual contact with the
terrain. The machine of the present invention is capable of-
changing grade as may be necessary to ramp-on or ramp-off a
¦ s~ructure or to clear a natural obstruction. Means are also
¦ provided for permitting construction of super~elevation (banks)
into road curves where necessary. The machine of the present
invention is totally self-contained and is self-sufficient,
¦ requiring only a supply of crushed iee, bond water and fuel,
¦ and is designed to be operated by as few as tt~o men. Crushed
ice may be transported to the machine over the structure con
structed by means of, for example, end dump type vehicles~
although other more efficient means of transport may be used
for the crushed iee. Bond water may be delivered to the
~ machine in the same manner 2S the crushed ioe, although it is
I possible that a portion of the delivered crushed ice m~ay be
diverted to an on-board ice melter to provide the necessary
bond water.
Referring now to the drawings, wherein like reference
i numerals represent identical or corresponding parts throu~hout
the several views, and more particularly to Figures 1-6 there-
-15-
11
1 }L~85~8
of, reference numeral 10 indicates generally a preferred
embodiment of a crushed ice placement and bonding machine in
accordance wi~h the present invention. As illustrated in
Figure l, the machine lO moves from the right to the left as
the ice aggregate road 14 is being constructed over the under-
lying terrain 12. The terrain 12 may be, and is usually, an
i uneven surface? and may consis~ of ecologically sensitive
I tundra, The machine lO of the present invention is designed
¦ to construct an ice aggregate roadway 14 over the terrain 12
I without having machine contact with the terrain 12 to avoid
¦ damage thereto.
I The machine 10 of the present invention includes left and
right support modules or carriages 16 and 18, tbe contents and
functions of which will be described in greater detail herein-
after. Each module 16 and 18 is supported by a longitudinally
extending outrigger frame 20 and transport wheels 22. A main
frame 24 extends transversely between modules 16 and 18 at
~he forward portions thereof.
Mounted to the forward portions of modules 16 and 18 and
extending forwardly over the area of the roadway being formed
is a distribution and grade box assembly indicated generally
¦I by reference numeral 260 The distribution and grade box assem-
¦ bly 26 includes a flexible outer guide frame 23 and a movable,
I substantially rectangular distribution and grade box or hopper
1 30.
The outer guide frame 28 includes rear vertical frame
members 32 and 32' whose lower ends are connected by a trans-
verse rear frame member 33. This structure provides an openrear end for the frame 28, for a purpose which will be made
¦ clear hereinafter.
Il,
-16-
' 11
~ 5~
¦I Frame 28 urther includes left and r;ght generally
¦ C-shaped side frame members 34 and 36 which are preferably
¦ pivotally mounted to the lower parts of vertical frame members .
32 and 32' as at 35 and 37, respectively. The forward por-
tions of side frame members 34 and 36 are connected by a front
transverse frame member 38.
Frame 28 is connected to the support modules 16 and 18 by
means of left and right transport hydraulic cylinders 40 and
j 42, respectively, and associated four-bar linkages 44 and 46
j equipped with lateral sway braces 44' and 46'. This permits
the guide frame 28 to be elevated relative to the finished ice
aggregate surface 14.
Mounted at the top ends of vertical frame members 32 and
1 32' are a pair of pulleys 48 and 50, respectively, for support-
I ing cables 52 and 54 which are connected between the front
j transverse frame member 38 and left and right guide frame warp
cylinders 56 and 58, respectively, whose lower ends are secured
to vertical frame members 32 and 32'. The cylinders S6 and
58 and ~ssociated cable and pulley assemblies permit the angle
oE the guide frame 28 relative to the finished surface to be
adjusted up or down. Further, the guide frame 28 may be tilted
transverse to the direction of travel of the machine 10 by
differential use of the cylinders 56 and 58. This pelmits
construction of a super-elevation (bank) into a road curve, as
! necessary g
¦ The distribution and grade box 30 consists of a U-shaped,
¦ open bottom box or hopper that includes side walls 60 and 62
¦ which may include at their forward portions slightly inwardly
! angled edges 61 and 63 for directing the flowing crushed ice
1i
"` ~ 5
Il
¦l inwardly when it is du~ped into the box 30 The box 30 includes
a forward compression box bracing member 64 connectin~ the two
~¦ side walls 60 and 62, and a rear wall 65. A pair of diagonal
!¦ braces 66 and 68 are also preferably provided and, together
ll with bracing member 64, provide lateral ri~idity to the guide
frame 28 through the support roller assemblies 88, 90, 92 and
94 of the distribution and grade box 30. At the lower inside
I edge of rear wall 65 is preferably provided a crushed ice
¦ smoothing edge 70 for smoothing the upper surface of the dis~
¦ trihuted ice aggregate.
¦, The distribution and grade box 30 is adapted for reciprocal
li movement within frame 2g by means of lef~ and right double rod
¦¦ hydraulic cylinders 72 and 74 which are preferably ~ounted
j within the openings of C-shaped side frame members 34 and 36
I (see Figure 4). ReferencP numerals 76 and 78 indicate the
exposed rods of cylinders 72 and 74, respectively. The distri-
bution and grade box 30 is propelled along the guide frame 28
by the attached cylinders 72 and 74 which, due to their double
! rod action, permit equal travel velocity in e;ther direction
~ or a given hydraulic fluid flow rate.
I Cylinders 72 and 74 are attached to the box side walls 60
¦¦ and 62 by means of trunnions 80 and 82, respectively~ The
¦¦ cylinder rods 76 and 78 are attached at each end of frame
Ij members 34 and 36 at points 84, 84' and 86, 86 7 .
l, Two pairs of support roller assemblies are provided on
¦1 each side of assembly 26 for coupling the grade box 30 to
frame 28. The roller assemblies are indicated generally in
Figures 1, 5 and 6 by reference numerals 88, 90, 92 and 94.
As illustrated with greater particularity in Figures 2-4,
rcller assembly 88, for example, includes upper and lower
l!
J -18-
.
1~8855~3 ;
j rollers 96 and 98 connected to the side wall 60 for movement
I along side frame member 34, while roller assembly 90 includes
j side rollers 100 and 102 mounted to a common support flange .
! 104 which is also connected to side wall 60. Roller assemblies
1 92 and 94 are similarly constructed and mounted for movement
i along side frame member 36. .
Attached to the rear outside bottom edge of rear wall 65
~ of box 30 is a spray bar assembly indicated generally by
¦I reference numeral 106. Referring to Figure 8, a sectional
¦I view through the spray bar assembly 106 is illustrated and is
¦ seen to include an upper metal enclosure 108 and a lower metal
enclosure 110 within which is positioned insulation 112. A
vent ~14 i5 preferably formed in upper enclosure 108. Extend-
¦ ing longitudinally within the spray bar assembly 106 is a
lS heated water supply pipe 116 and a heated water return pipe
118. A plurality of spray nozzles 124 are connected in parallel
in communication with supply pipe 116. Each preferably include
a diaphragm check valve control 120 which requires a certain
minimum pressure in supply pipe 116 for delivering the bond
water supply to spray nozzle 124. ADY of the bond water not
emitted by the individual spray nozzles 124 is returned to
¦ circulate through the system via return pipe 118, as will be
described in greater detail hereinafter.
Extending downwardly from the enclosures 108 and 110 of
spray assembly 106 to the top surface of the ice aggregate 14
is a flexible skirt 122 which may be formed, for example, of
Hypalon, a synthetic rubber material which re~ains flexible at
.~ ¦ -40F. The provision of skirt 122 provides an enclosed
' ~1
1 9 -
: i!
!l
I'
55~3
¦I vapor-saturated re~ion 12S in the spray area to prevent
¦ evaporative cooling of the spray bond water prior to its
¦. impingemen~ upon ice aggregate surface 14. In addition to
li contaîning the water vapor to preven~ further evaporation and
1¦ consequent cooling, flexible skirt 122 prevents any apprecia-
¦ ble build-up of frozen water on i~s surface. The spray bar
assembly 106 is attached to the rear of distribution box 30
wi~h sufficient clearance to permit flexing of the skirt 122
and consequent spalling-off of collected ice.
Referring now to Figure 7, reference numerals 130 and 132
i indicate side extensions of the spray bar assembly which slope
¦I downwardly to permit bonding of side slopes 138 and 140 of the
, ~ ice aggregate road 14 if desired. The slope bonding spray bar
I extensions 130 and 132 include skirt sections 134 and 136 7
15 ! respectively, which serve the same function as the main skirt
122 described above.
Referring now to Figure 9, there is illustrated a top
sectional view of the left support module or carriage 16 which
typically may include insulated walls 142 and a plurality of
¦ access doors 144, 146 and 148. Reference numeral 150 indicates
¦ an operator control area having windows 152. Reference
¦ numeral 154 indicates an equipment area which may include, for
example, an engine/generator 156, a fuel storage area 158, a
bond water storage tank 160 and a fuel and water transfer
mechanism 162 which may include hydraulic pumps, or example.
The right support module or carriage 18 is illustrated
schematically in Figure 10 and is seen to include insulated
walls 164 and access doors 166 and 168. Reference numeral 170
¦l indicates an intermediate fluid heater for bond water, while
I -20-
jl
I _
reference numeral 172 indicates a heat exchanger and circulating
¦ pump assembly. Bond water storage is provided in module 18 by
bond water storage tank 174.
I Referring now to Figure 11, there is illustrated a
1I schematic representation of a heating and circulating system
for the bond water which may be utilized with the preferred
apparatus and technique of the present invention~ Reference
numeral 170 indicates a fluid heater for an intermediate, non-
11 freezlng fluid, such as anti-freeze. A Eluid c;rculating pump
¦ 176 pumps the intermed~ate fluid through heat exchanger 178
and conduit 180 back to fluid heater 170~ Bond water contained
in storage tank 174 is pumped by circulating pump 182 through
heat exchanger 178 where it is heated to the desired temperature
I The heated bond water from heat exchanger 178 is fed through
¦ delivery pipe 186 to the heated water supply pipe 116 of spray
I nozzle assem~ly 10~ via a flexible hose 188 connected between
¦ the modules ~nd the spray assembly. The return path for the
excess heated water is by way of return pipe 118, another
I flexible hose 190 and pipe 196 to heated bond water supply
li tank 160. Pump 182 insures continuous circulation of the
Il heated bond water thro~gh the spray nozzle assembly 106 to
¦~ prevent freezing of the bond water. Between the return pipe
118 and pipe 196 is positioned a pressure control valve 192
~ which is set by the operator to establish the required spray
2.5 I nozzle pressure for the desired quantity of bond water to
¦¦ emanate from the diaphgram controlled spray nozzles 124 in
supply line 116. A manual control valve 194 is preferably
connected in parallel with valve 192 and is used by the opera
tor to bypass valve 192 to thereby reduce the pressure in
~21-
I!
I'`"`
5~
~j pipes 116 and 118 below the set point ~f the diaphragm check
¦ valves 120 (see Figure 8) to thereby prevent water spray with-
¦ out stopping the circulation of the heated water. A temperature
I sensor 184 is provided adjacen~ line 186 to control the fluid
~¦ heater 170 to maintain the bond water temperature at an
¦ operator controlled set point which will be a function of the
¦ ambient temperature.
I In operation~ after harvesting, crushing and removal of
1l the detrimental fines, the resultant ice aggregate is dumped
¦ into the distribution and grade box 30 by means of a conven-
tional crushed ice transporter 123 which is adapted to be
positioned between the support modules 16 and 18 as ilius-
trated in Figures 5 and 6. The rear dump type truck 128 is
simply backed over the finished ice aggregate surface 14 into
¦ the space between the support modules 16 and 18 and its
contents are discharged over the forwaL-d, transverse main
frame 24 into the distribution box 30.
The ice aggregate is dist-cibuted and graded by the
¦ orward travel o the box 30 pcopelled by the double rod
¦ cylinders 72 and 74 while the support modules 16 and 18 are
¦ held stationary. The box 30 may be caused to travel to the
¦ end of the distribution box guide frame 28 if sufficient
crushed ice ;s available, or to some intermediate point.
; During forward travel of box 30 (from right t~ left as illus-
I trated in Figure 1), the crushed ice therein is distributed
and graded by the rear wall 65 and the crushed ice sm~bthing
edge 70 in combination with the side walls 60 and 62. Spraying
of the bond water may occur during the distribution and
grad;ng pass, or in a subsequent pass or passes. In either
~ !
, -22-
; ,
S5~
event, the distribution box 30 is traversed back and forth
within the limits established by the quantity of crushed ice
available and the terrain flll requirements until the desired
number of spray passes have been effected. In the preferred
em~odiment, two or three spray passes have been found to be
sufficient to establish the desired depth of penetration of
bond water; however, under certain circumstances, more or less
bond water passes may be used. It is believed from present
investigations that the strength of the final structure increases
with the number of bond water passes.
Once the requisite number of spray passes have been made,
the guide frame 28 is lifted by the transport cylinders 40 and
42 and the machine is propelled forward by the support and
transport wheels 22 until the forward edge of the bonded ice
aggregate is beneath the spray bar assembly 106. Alternatively,
the guide frame 28 may simply be slid along the bonded crushed
ice until the unbonded crushed ice edge is reached.
When the machine 10 has been transported forward to the
unbonded crushed ice edge, the guide frame 28 is lowered until
~0 the rear of the distribution box 30 is at the elevation of the
bonded ice aggreyate. The slope and warp of the frame 28 may
then be adjusted if any change is to be made for the next
section of road by means of the cylinders 40 and 42. ~dditional
crushed ice is then dumped into the distribution box 30, if
needed, and the foregoing process is repeated. Incremental
slope and warp changes will ordinarily be less than 1 D -2, and
can therefore be easily accommodated by the flexible guide frame
and distribution box.
During operation of the machine, flow of the bond water
will be continuous through the piping system illustrated in
Figure 11 in order to maintain freeze protection. When bond
-23-
88558
~ water is to be applied, the pressure in the flow loop is
ii increased to a value above the opening pressure of the diaphragm
' check valves and to that required for the design flo~7 through
¦ the respective nozzles. At the end of the spray cycle, the .
5 I pressure is reduced and the check valves close. The heated
j bond water flo~ing through the pipes in contact with the
¦ bottom of the metal enclosure (note Figure 8) will prevent
¦ freezing of the water nozzles 124 through conduction. In the
I event that insufficient heat is availabl~ for this purpose,
j sùpplemental heat may be provided, for example9 by electric
¦I heat cables strategically located near the nozzles.
Il As may be appreciated from the foregoing9 the machine of-
11 the present invention is capable of constructing an ice aggre-
¦¦ gate roadway continuously from the surface of the structure
being built, thereby avoiding machinery contact with the
underlying terrain. This feature is of extreme importance in
those areas where the substrate over which the temporary
structure is being built is ecologically sensitive to high
ground pressure loading as occurs with most conventional con-
2a struction equipment. The present invention produces a smooth,
I finished,free surface regardless of irregularities in the
jl terrain. The preferred embodiment of the machine may be readily
j disassembled into units of such volume and weight as to be
l easily moved into remote areas by helicopter for use in the
j construction of~ for example, air strips for large car~o .
carrying aircraft, or the like.
The technique of the present invention permits high latitude
~intertime construction seasons to be extended by both earlier
¦I construction in the Fall and later utilization in the Spring
~ -24-
,'
:. l
8558
than is commonly found with more conventional snow construction
techniques.
Obviously, numerous modifications and variations of the
¦ present invention are possible in light of the above teachin~s~
It is therefore to be understood that within the scope of the
appended claims, the inven~ion may be practiced otherwise than
as specifically described herein.
I
I
Il -25-
