Edgar, Mathis, McGary and Potter 0
Frost Heave Mitigation Using Structural Polymer Injection 1
TRB #14-1029 2
August 1, 2013 3
Word Count: 4724 4
Figure Count: 11 fig = 2750 5
Total Word Count: 7474 6
7
Thomas V. Edgar 8
Department of Civil and Architectural Engineering 9
1000 E University Ave., Box 3295 10
University of Wyoming 11
Laramie, WY 82071 12
307- 766-6220 13
Corresponding Author 15
16
Roy Mathis 17
Concrete Stabilization Technologies, Inc 18
8500 East Warren Ave 19
Denver, CO 80231 20
303-306-9191 21
23
Tim McGary 24
Wyoming Department of Transportation 25
3411 South Third Street 26
Laramie, Wyoming 82070 27
307-745-2100 28
30
John Christopher Potter 31
Formerly: Department of Civil and Architectural Engineering 32
1000 E University Ave., Box 3295 33
University of Wyoming 34
Laramie, WY 82071 35
Currently: Nebraska Public Power District 36
6089 South Highway 25 37
Sutherland, NE 69165 38
308-535-5933 39
40
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 1
Frost Heave Mitigation Using 41
Structural Polymer Foam Injection 42
1 TRB #14-1029 43
Frost heave is caused by water freezing into ice lenses in silty subgrade soils. Subgrade frost 44
heaving may cause significant distress in a flexible pavement. This paper summarizes a two 45
year study of a successful mitigation procedure using structural polymer injection to create 46
a thermal barrier that reduces heat loss below the pavement. 47
The contractor had problems breaking through a tough quartzite ridge above 48
subgrade during the construction of Wyoming Highway 70 four miles (6.4 km) west of 49
Encampment, WY. As an alternative to excavation, he placed three feet (1 m) of silty fill over 50
the ridge and tapered the vertical alignment to match the approaching grades. The fill is 51
classified as an SM/A-4/A-2-4. More than three inches (75 mm) of heave have been 52
measured over a 100 ft (30 m) distance across the ridge. 53
To mitigate the heave, a three inch (75 mm) thick layer of structural expanding 54
polymer (Uretek 486 STAR) was injected immediately below the sub-base course at a depth 55
of 18 inches (450 mm). The foam both supports the road surface and creates a thermal 56
blanket having a significant R value to reduce heat loss. Surface surveying over two winters 57
showed that the heave was reduced from 3 to 0.5 inches (75 to 13 mm), undetectable to the 58
motorist. The thermal regime was determined by installing thermistors above and below 59
the foam layer in six bore holes. The data shows that the temperatures below the polymer 60
stayed at or above 0oC, hence controlling the heave. Untreated areas still showed three 61
inches of movement. This is a novel technique which is rapid, controlled and safe. 62 63 Very local frost heave at milepost MP51.8 of Wyoming WYO-70, the Battle Mountain Highway, has 64
been great enough to create dangerous driving conditions for vehicles and trailers. The site is about 4.5 65
miles west of Encampment, WY. A silty/fine sand backfill was used over a rock outcrop for a distance 66 of about 100 feet and a frost heave over 3 inches (75 mm) commonly develops across this stretch during 67
the winter. The highway is closed during the winter at the Forest Service Boundary one mile (1.6 km) to 68
the west and has become a popular snowmobile trailhead. Vehicles pulling snowmobile trailers 69
accelerate rapidly on the downhill slope leaving the parking lot and are often traveling much faster than 70 the posted speed. When the vehicles hit the heave’s sharp bump and the subsequent one and one-half 71
inch deep dip in the center of it, they can become airborne and poorly restrained snowmobiles have been 72
thrown from their trailers. (1) 73 74
BACKGROUND 75 During construction in the 1980’s, the contractor encountered problems excavating a tough quartzite 76
caprock outcrop running obliquely to the highway alignment. After trying unsuccessfully to remove the 77 rock above subgrade, it was agreed that the contractor could alter the vertical alignment by placing 78
approximately 3 feet of subgrade soil over the rock and smoothing the vertical grade over several hundred 79
feet to the east and west of the problem location. The soil texture of the fill, a silty sand to sandy silt, is 80 highly susceptible to frost heave. In addition, the outcrop acts as a dam for the groundwater underflow 81
and water typically flows two to three feet (0.7 to 1.0 m) below the pavement surface. Hence, the three 82
factors required for frost heaving are present: cold temperatures, a suitable soil, and water. 83 Frost heave developed during the first winters of operation. A variety of remediation techniques 84
have been attempted at the site. Two drainage pipes were installed across the road at different times 85
during the 1990’s. In 2001, two 100 foot long (30 m) lateral drains were installed 22 feet (6.7 m) north 86
and south of the highway centerline running parallel to the side ditches. None of these techniques have 87 substantially reduced the effects of the heaving on the road surface. 88
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 2
PROPOSED REMEDIATION 89 Tim McGary, Wyoming Department of Transportation (WYDOT) District 1 Maintenance Engineer, and 90 Roy Mathis, Concrete Stabilization Technology (CST), recommended a novel procedure of injecting a 91
structural polymer foam into the subgrade of the road to level the surface and to provide a thermal barrier 92
to reduce heat loss from the lower subgrade. An average of three inches of CST Uretek 486 STAR #3 93
was injected at a depth of 18 inches through the worst sections of the heave and then tapered out away 94 from that zone to provide a smooth transition. The University of Wyoming (UW) was contacted to 95
perform installation of data acquisition instrumentation and provide two seasons of monitoring and 96
analysis. This paper presents the results of that study. This application of the technology has not been 97 found after an extensive literature search. 98
99
FROST HEAVE POTENTIAL 100 Frost heave is caused by the expansion of water as it freezes in a soil mass (1). The water may be inside 101
the soil void volume in either a saturated or non-saturated condition. This condition is referred to as 102
interstitial water freezing and, in general, is not significant in coarse grained soils because the water can 103
flow during phase change. Rapid freezing causes the freezing front to solidify the interstitial water and 104 not allow additional water to enter the void space. Water freezing in clays cannot flow out of the 105
structure because of the low hydraulic conductivity. While water can expand by nine percent as it 106
freezes, the water comprises only a fraction of the total volume in clay so the actual volume change is less 107 than the nine percent. Expansion in non-saturated clays may be closer to three percent. 108
Far more significant is segregational freezing (2). When the freezing front is advancing slowly 109
into the soil, water from below can be attracted to the ice forming in the void space. As more water bonds 110 to the ice, ice lenses can form composed of nearly pure water, excluding the natural salts from the ice 111
structure. The salts cause the mineral concentration of the surrounding water to increase, which creates 112
freezing point depression allowing water to flow at temperatures well below freezing. Hence, the water 113
around the ice stays liquid and allows more water to flow and bond to the ice. Since this process can take 114 place over a winter season, the ice lenses can become thick, lifting the soil above it and creating heave. 115
These lenses are commonly up to 0.5 inches in thickness, and in aggregate with other lenses, can cause 116
several inches of heave. 117 Two soil characteristics are necessary for segregational freezing to cause heaving (3). The soil 118
must have sufficient hydraulic conductivity so that the water can flow with minimal head loss. Silt and 119
fine sand soils can retain sufficient conductivity in both the saturated and non-saturated states. Secondly, 120
the soil requires sufficient capillarity so the water can be drawn up from a deeper water source. While 121 clays have high capillarity, their conductivity is too small to allow enough water movement to affect the 122
heave. Silts and fine sands have the right combination of these properties to encourage heaving in 123
freezing soils. 124 125
CONVENTIONAL REMEDIATION TECHNIQUES 126 Three factors are required for heaving to occur: surface temperatures below freezing, silts and fine sand 127 and a source of water. Heaving can be prevented by removing one of these three factors (4). The 128
preferred prevention method is to remove the silt and sand and replace it with a coarser material, like 129
extending the sub-base down below the depth of freezing. A second method of control is to remove the 130
water from the site. When the phreatic surface is deep enough, the ability of the water to flow vertically 131 through capillarity is greatly reduced. Alternatively, moisture barriers such as a thick gravel layer above 132
the phreatic surface will significantly reduce the capillary action. Soil entirely wrapped in a 133
geomembrane will allow the water inside the membrane to freeze, but prevent additional water from 134 flowing inside the wrap. 135
A third procedure is to create a thermal blanket below the sub-base to insulate the soil and allow 136
the heat from below to prevent freezing of the upper soil. In a separate successful case, the Wyoming 137 Department of Transportation has used layers of extruded polystyrene rigid foam insulation panels placed 138
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 3
flat on a prepared base and then placed sub-base and base aggregate on top of it on US-189/191 in 139
Bondurant, WY where it runs parallel to the Hoback River. 140 Each of these techniques requires extensive excavation and material handling to be effective. 141
Construction can take weeks to months, often requires detours which are inconvenient to the local 142
residents and the traveling public, and impacts the safety of the workers and the travelers. 143
144
SITE CHARACTERISTICS 145 The site is located on Wyoming Highway 70, known as the Battle Mountain Highway, between 146
Encampment and Baggs, WY and was constructed in the early 1980’s. Figure 1 shows the site being 4.5 147 miles (6.5 km) from Encampment and one mile (1.6 km) from the Sierra Madre Unit of the Medicine 148
Bow National Forest boundary. The road is closed at the boundary during the winter and has become a 149
popular snowmobile trailhead. The traffic volume is low, but consists mainly of trucks pulling 150 snowmobile trailers. 151
Three sets of geologic/geotechnical investigations have taken place at the site. This has resulted 152
in three sets of drains being constructed in the area. The borings indicate that the pavement thickness is 153
between 4.5 and 7.0 inches (115 to 175 mm). The base and sub-base are indistinguishable and are 8 to 10 154 inches thick (200 to 250 mm). The fill thickness is variable between 3 to 8 feet (1.0 to 2.4 m) and the 155
bedrock surface is highly irregular. While the bedrock surface influences the groundwater flow, the 156
heave is contained in the upper 3 feet (1 m). 157 158
FIGURE 1 Frost heave site, MP51.8, WY-70, 4.5 miles west of Encampment, WY.
Frost Heave
Site
MP 51.8
WYO-70
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Edgar, Mathis, McGary and Potter 4
Geology 159 The road obliquely crosses a quartzite ridge outcrop which has a strike of N80W and a dip of 10-15
o. The 160
buried caprock appears to be about 10 feet (3 m) thick and the layer beneath it has weathered more and 161
was easier to excavate. The top of the caprock appears to be flat under the road, while the layer 162
underneath appears, due to drilling which has occurred at the site, to slope steeply to the north. One 163
consequence of the caprock is that it acts as a barrier to groundwater flow. Water depth upstream of the 164 caprock is between 3 and 5 feet (1 to 1.6 m) below the road surface while water downstream is 6.5 feet or 165
deeper below the road surface. 166
The caprock is extremely tough and the contractor could not remove it using conventional 167 techniques. It was agreed that the contractor could place three feet (1 m) of backfill soil over the caprock 168
and adjust the slopes uphill and downhill of the rock over the distance of several hundred feet. The fill 169
the contractor used is classified as a silt or silty sand, SM (Unified) and A-4(0) and A-2-4(0) (AASHTO), 170 i.e., the worst material for frost heave. The soil combined with the high water levels has created a short, 171
high heaving section of highway. 172
173
Drains 174 Three sets of drains have been constructed to mitigate the frost heave. The first was a 12 inch (30 mm) 175
corrugated metal pipe which extended from ditch line to ditch line under the road. This is located about 176
40 feet downstream from the caprock. It conveys water from the north ditch to the south ditch and 177 controls the depth of water which may flow under it. However, it probably had little or no effect on the 178
heave upstream. 179
A second drain was installed in the middle of the heave area on top of the caprock at a depth of 3 180 feet (1 m). It extends from the centerline of the road to the south where it daylights on the side of the 181
embankment. It apparently drains a little water in the spring, but the water level during the rest of the 182
year is 1 to 4 feet (0.3 to 1.3 m) below the pipe. When the trench was backfilled, a non-heaving soil was 183
used as fill. During the winter when the soil around the trench heaves several inches, the heave above the 184 trench is about one inch and creates a dip. This dip has exacerbated the problem with the road 185
A third pair of drains was constructed parallel to the highway and 22 feet (6.7 m) north and south 186
of the road’s centerline. The drain was designed to be 5 feet (1.5 m) deep, however, the contractor hit the 187 same bedrock and could not excavate below that level. Records were not kept of that work and 188
information on rock depths is not available. 189
190
PRE-CONTRACT SITE VISIT 191 Representatives from WYDOT, CST and UW met at the site on December 14, 2010. The heave area was 192
outlined and a general remediation plan was developed. A survey grid was established on the East Bound 193
Lane. Surveying points were set at 10 feet intervals over a distance of 300 feet along the South Edge 194 (White Line) (SEEB) and the Centerline (CLEB) of the East Bound Lane and the centerline of the 195
highway (CL). The effect of heaving on the northern West Bound Lane was not considered severe 196
enough to require surveying. As no baseline measurements were available, it was not possible to 197 determine the amount of heave at that time. 198
UW returned to the site on January 26, 2011 and resurveyed the CLEB and the CL. The south 199
edge was not surveyed because the snow and ice had built up sufficiently that it was not possible to obtain 200
representative elevations. The elevation differences between the two dates of surveys on the centerlines 201 clearly indicated the lateral extent of the heave zone, between Sta 1+50 and 2+40. Based on that 202
information, UW came to contract with WYDOT and the project proceeded in the fall when the 203
temperatures were cooler and the asphalt a little stiffer. 204 Three types of tests were used in this study, surface surveying, thermistors distributed with depth 205
in six boreholes, and shallow piezometer readings. Figure 2 shows the locations of the six boreholes and 206
the piezometers. It was also decided to survey the West Bound Lane along the centerline (CLWB) and 207 the north edge (NEWB). These five lines are also shown on the figure. 208
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 5
209
210 211
CONSTRUCTION 212 Construction began on October 11, 2011. All of the material and equipment was contained in a semi-213 trailer and a service truck. The structural foam, Uretek 486 STAR #3, is a two part polymer. Each part is 214
pumped through hoses to a gun, where the parts are mixed and injected to the required depth. 215
On arrival, the crew laid out a six feet by six feet (2 m by 2 m) grid. A ¾ inch (19 mm) hole was 216
drilled at each intersect to a depth of 18 inches (500 mm) and a 24 inch (610 mm) long pipes was placed 217 in the holes. A series of string lines were set up as elevation references and the foam was injected 218
through the gun into each pipe and entered the soil at a depth of 18 inches, just below the base course. 219
The foam was injected until the surface rose three inches. Adjustments were made to level the surface 220 between the initial injection points and the surface was tapered over a 30 feet long distance before and 221
after the fully treated zone. The surface was also tapered across the width of the West Bound Lane. 222
223
RESULTS 224
Surveying – Longitudinal Elevation Differences 225 Figure 3 shows the frost heave occurring on the Centerline of the East Bound Lane. The thinner solid 226
black line is the heave determined on January 26, 2011 before the treatment was applied. The maximum 227 heave measured is 2.6 inches at Sta 1+90, but the significant feature is the 1.3 inch drop at Sta 2+10 228
followed by the 1.0 inch rise in the next 10 ft. The dip, right in the middle of the travel lane, has created 229
significant problems and complaints. 230 The heavy black line on the bottom represents the thickness of the structural polymer foam along 231
the centerline of the lane. The secondary vertical axis indicates thicknesses of 0 to 3 inches (0 to 75 mm) 232
with the average thickness being a little less than three inches. 233 The colored lines are the differences between the measured elevations and the baseline elevations 234
after the foam treatment. The dashed lines are from the first season (2011-2012) while the solid lines are 235
from the second season (2012-2013). The maximum heave under the highest bump is less than one-half 236
an inch. One set of readings taken on March 5, 2012 reaches 0.7 inches between Stas 1+50 and 2+60 237 while the rest of the readings are less than 0.5 inches. The resulting heave is essentially unnoticeable to a 238
driver. 239
FIGURE 2 Plan view showing five survey lines, the six instrumented boreholes and piezometers.
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 6
FIGURE 3 Elevation differences along center of east bound lane (CLEB). 240
241 The heave along the centerline of the highway is shown in Figure 4. The heave prior to treatment 242
measured on January 26, 2011, is about 2.9 inches at Sta 1+90. There is no dip along the centerline 243
because the French drain on the buried caprock extended from the centerline to the south. The foam 244
thickness is very uniform at three inches over the center of the treated zone. 245 A small amount of heave occurs at Sta 2+10 where the caprock is closest to the surface. Two 246
possible reasons may be the cause. First, it is possible the caprock may alter the thermal regime locally 247
which could provide more water adjacent to the freezing front and create more ice lenses. As no 248 temperature gages were installed on the centerline, it is not possible to verify that hypothesis. A second 249
reason may be that the taper in foam thickness to the north occurs at the centerline, so it is possible that 250
some heat loss is occurring here causing the temperature to drop lower at that point. Nonetheless, the 251 heave is significantly less than that before the treatment. 252
During the initial negotiations for the project, the frost heave on the north side of the highway 253
was not considered to be a concern. The bump was not severe and there was not as much driver 254
discomfort on the north side. Surveying was not performed on the north side during the first two site 255 visits, but was started during the research phase. Figure 5 shows over 3.0 inches of heave occurred on the 256
north edge during the first season (dashed) while 1.75 inches occurred during the second season. 257
The most likely reason for this difference in heave is because of the road surface condition. An 258 overlay was performed on the road in the mid 1990’s. A tack coat was not applied between the initial 259
FIGURE 4 Elevation differences along center of the highway (CL). 260
261
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Edgar, Mathis, McGary and Potter 7
FIGURE 5 Elevation differences along the north edge of the west bound lane (NEWB). 262
263
surface and the overlay as an experiment to reduce maintenance costs. After milling the surface after the 264 injection, the thickness of the overlay was less than one inch over much of the area. During the spring 265
and summer of 2012, plates of the asphalt began to slide on the cold joint with the traffic, to the point of 266
pinching the instrumentation cables crossing the road. A decision was quickly made to place another 267
overlay on the stabilized surface. The overlay made the surface black as opposed to the lighter grey of the 268 weathered asphalt. The different albedo most likely caused the change in heave between the first and 269
second year heave. 270
271
Surveying – Transverse Elevation Differences 272 The significance of the heave reduction can be seen in the transverse direction across the highway. Figure 273
6 shows the heave at Sta 2+00. The heavy black line on the bottom shows the full thickness of the 274 injection on the East Bound Lanes (South/Left) and the taper in thickness to zero on the north edge. The 275
thin line between -6 and 0 ft is the heave measured on January 26, 2011 before the treatment. The dashed 276
lines are the readings the first year after the injections and the solid lines are the readings during the 277
second year. The heaves at -6 ft, the centerline of the East Bound Lane are all below 0.5 inches. A 278 portion of the heave on the south edge of the lane may be attributed to irregular injection adjacent to the 279
FIGURE 6 Elevation differences across the highway at Sta 2+00. East bound lane is on the left. 280
TRB 2014 Annual Meeting Original paper submittal - not revised by author
Edgar, Mathis, McGary and Potter 8
embankment slope. Injection would stop when the foam would begin to flow out the embankment face. 281
One modification to the injection plan for future work would be to create a vertical barrier along the 282 outside shoulder. This barrier would prevent lateral loss of foam and also reduce the heat loss to the side. 283
The ground surface is covered by a layer of snow during the winter that acts as a thermal blanket. 284
The ground temperature under the snow stays right at 0oC (32
oF). The warmth on this side compared to 285
the colder surface temperature under the cleared road surface could also affect the depth and rate of 286 freezing and allow somewhat more heave to occur along that edge. This temperature difference could 287
also explain in part why shoulders tend to show more distress than the pavement next to them. 288
Surrounding Stations show similar patterns, with the heave on the right decreasing in both 289 directions while the heave in the CLEB remains at a minimum. 290
291
Temperatures 292 The temperatures below the road surface were determined at boreholes one through six, shown in Figure 293
2. The top three thermistors in all the holes were located at fixed distances 1.33, 1.87 and 2.67 feet (410, 294
560 and 820 mm) below the surface, Figure 7. The top thermistors were located just above the foam 295
while the second thermistor was just below the foam. The fourth and fifth thermistors were spaced 296 depending on the depth of the hole. Temperature readings at all thermistors was collected every hour 297
November 11, 2011 to May 5, 2013. 298
Temperature readings for the four thermistors in Hole #4 over the two winter seasons are shown 299 in Figure 8 and for the three thermistors in Hole #1 are shown in Figure 9. Both of these holes are located 300
on the centerline of the East Bound Lane, with Hole #4 having 3 inches of foam and Hole #1 having none. 301
The average temperature in Hole #4 during the first year is about -2oC with a minimum temperature about 302
-3oC. The average temperature in Hole #1 during the same time is about -3
oC while the minimum is at -303
6oC. 304
The key temperature readings are at the second and third depths, 1.87 and 2.67 feet (560 and 820 305
mm), immediately below the polymer injection. The average temperature at the 1.87 foot depth in Hole 306 #4 is at right at 0
oC with a small dip to -1
oC while the average temperature in Hole #1 is approximately -307
2oC with a minimum temperature of -4
oC. The green line representing the data at 2.67 feet depth is well 308
309
310 311
FIGURE 7 Location of top three thermistors relative to the pavement and the foam. 312
313
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Edgar, Mathis, McGary and Potter 9
314
FIGURE 8 Temperature readings in top three thermistors in Borehole #4. 315
FIGURE 9 Temperature readings in top three thermistors in Borehole #3. 316
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Edgar, Mathis, McGary and Potter 10
above zero in Hole #4 and well below zero in Hole #1. No freezing is taking place below the foam layer 317
in Hole #4 so the heave there is minimal. Conversely, the frozen depth is well below 2.67 feet in Hole #1. 318 No heaving occurs in the area of Hole #1 because the soil is coarser and is not frost susceptible. 319
Figure 10 compares the temperature data for the first year in Hole #4 to the frost heave over that 320
time at Sta 2+00 along the five survey lines. Specifically, the heavy black dashed line is the heave 321
measured along the centerline over Hole #4. Very little heave occurs until the temperature at 1.87 feet 322 briefly drops below 0
oC. Even then, the heave is small because the depth of frost penetration is very 323
small. 324
Conversely, Figure 11 compares the temperature data to heave at Hole #3. Hole #3, located on 325 the centerline of the West Bound Lane, is in the taper zone and only has one inch (25 mm) of foam for 326
insulation. The red line at a depth of 22 inches is consistently below 0oC and the green line at depth 32 327
inches, decreases to zero on February 1, 2012 and stays on zero through the rest of the season. The heavy 328 dashed line is the centerline over Hole #3 and indicates that the heave increases progressively throughout 329
the season. The slower that the freezing front advances into the soil, the greater the opportunity for water 330
to flow upward and to freeze into an expanding ice lens. 331
The temperature variations during Year 2 (2012-2013) are similar to the temperatures during 332 Year 1 (2011-2012). The heave patterns are different in Year 2, which may be due to the black surface of 333
the pavement after the overlay was placed. Secondly, the movement of the thinned pavement in plates 334
during the spring and summer of 2011 cramped some of the thermistor cables and caused erratic 335 temperature readings in Holes #2, #3 and #6. 336
337
Conclusions 338 The process of injecting a polymeric foam into the subgrade to reduce frost heave is novel. The research 339
project has been a success in eliminating heave in a dangerous situation. Several important conclusions 340
can be reached concerning this process. 341
1. The three inch layer of foam injected below the base course of the highway has significantly 342 reduced or eliminated the frost heave under the road. It has been shown that the thermal regime 343
under the foam has altered the pattern of freezing associated with frost heave. There has been a 344
slight reduction in water level after the foam was injected which could have decreased the 345 unsaturated flow to the freezing front. The foam may have provided some structural support to 346
spread out the heaving and reduce local effects, however, this was not tested in this project. 347
2. The process can be accomplished in a short time frame. In this case, the project was functionally 348
completed in five working days. To reconstruct a highway with foam insulation panels could 349 easily take weeks or months. Special site preparation and control is required when placing the 350
panels and placing the sub-base material above it. 351
3. The operation can be performed in a single lane, so that a traffic lane can remain open all the 352 time. Simple routing with Stop/Slow signs and cones is sufficient. Also, there is no need for 353
detours. Hence, safety is an important factor for both the workers and the driving public. 354
4. Depending on the quality of the road surface, the injection can be performed without additional 355 surface treatment. 356
357
Acknowledgment 358 Many people’s contribution have made this project a success. Christopher Potter performed the initial 359 research and has written a thesis based on the first year of this work. Jordan Roberts and Logan 360
Williamson collected data for the second year. 361
Tim McGary, WYDOT District 1 Maintenance Engineer, initiated and promoted the project. The 362 continued support provided by Scott Kinniburgh, Saratoga Maintenance Foreman, and his dedicated crew 363
gave a face and a purpose to this research. Their help is all greatly appreciated. 364
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Edgar, Mathis, McGary and Potter 11
365
FIGURE 10 Temperature and heave comparison in Borehole #4, Year 1. 366
367
368
FIGURE 11 Temperature and heave comparison in Borehole #3, Year 1. 369
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REFERENCES 370
1. Potter, J.C. Frost Heave Mitigation Using Expanding Structural Polymer. M.S. Thesis, Department of 371 Civil and Architectural Engineering, University of Wyoming, Laramie, WY, 2012. 372
2. Lay, R. Development of a Frost Heave Test Apparatus. M.S. Thesis, Department of Civil and 373
Environmental Engineering, Brigham Young University, Provo, UT, 2005. 374
3. Guthrie, W.S. and A. Hermansson. Frost Heave and Water Uptake Relations in Variably Saturated 375
Aggregate Base Materials. In Transportation Research Record: Journal of the Transportation 376
Research Board, No. 1821, Transportation Research Board of the National Academies, Washington, 377
D.C., 2003, pp. 13-19. 378
4. Evans, G.L., M.A. Truebe and G.L. Hanek. Monitoring Report of Frost Heave on Warm Lake Road. 379 In Transportation Research Record: Journal of the Transportation Research Board,No. 2204, 380
Transportation Research Board of the National Academies, Washington, D.C., 2011, pp. 251–257. 381
TRB 2014 Annual Meeting Original paper submittal - not revised by author