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How to Maintain Gravel Road


Quiz Questions

1.In figure 1, the purpose of the crown on the gravel road is:
For a better and smoother ride on the gravel road.
For drainage
2. On figure 2, page 13, the reason that grave road is performing poorly is:
Too much raining in the area
A poor cross section with no crown on the surface and no ditches at the edge of the roadway to drain water off of the surface and away from the road
3.The angle and pitch of the moldboard to recover the aggregate from the shoulder of the road way, back to the face of the road is between:
30 and 45 degrees
50 and 60 degrees
4.The Moldboard pitch angel can make a difference in what kind of task can be performed. Which one of the tasks below can be done with varying the pitch angle of the Moldboard.
Aggressive cutting
Spreading
Light blading and dragging
All of the Above
5.The practice of windrow involves leaving a small amount of material along the side of the road to be pick up later when working across the road for filling small depressions.
True
False
6.A proper crown ensures :
water will drain off the roadway surface during a rain event.
Will make the ride smoother
7.Without a proper crown,
water will quickly collect on the road surface during a rain event or snow melt and will soften the crust
you simply have a flat dirt road
8. Figure 6 displays a correct crown. The recommended crown is a straight line from the shoulder to the centerline that rises approximately
¼ inch per foot (or approximately 2 percent)
1/2 inch per foot (or approximately 4 percent).
9.A condition known as high shoulders can occur along gravel roads almost anywhere people travel. Many slang terms such as "berms" or "“curbs" are used in the field to refer to this condition. The engineering term for this condition is secondary ditch and it is a good description of the situation. When a gravel road develops a high shoulder,
it restricts the surface water from draining into the designed ditch that can causes several problems.
It makes the road uneven
10.Quite often, the material pulled out onto the roadway from the shoulder is very hard to spread because of the vegetative material it contains. Multiple passes with the grader will be required to get the job done. Many agencies are turning to other mechanical means of breaking up the material (from something as simple as a disk or drag to sophisticated pulverizing equipment) to make the road safe for traffic
True
False
11.The recovered material from a high shoulder is not always suitable to be reused on the roadway. It may be best to cut the material loose, pull it onto the roadway, load it, and remove it. Although this can be very expensive,
It is better to remove it than to place it on the surface and contaminate the existing gravel.
Therefore, it is better to spread it around on the road and not to waste it.
12.If a road is scheduled to be re-graveled,
it is an excellent time to do shoulder work to get the roadway back into good shape.
Just re-gravel the entire road from ditch to crown.
13.Gravel roads are generally maintained by routine blading and adding gravel as needed either by “spot graveling” or re-graveling entire sections. However, almost any gravel road will gradually begin to show distress over time that requires more than routine maintenance to correct. The most common problems that develop are “berms” or secondary ditches that build up along the shoulder line and the shifting of material from the surface to the shoulder area and even onto the foreslope of the grade.
True
False
14.Problems with surface and shoulder shape can usually be corrected with the motor grader alone. Spring is the best time for this work as there is minimal vegetative growth and moisture is often present. The reshaping of the driving surface and the road shoulder can be done by cutting material with the motor grader and relaying it to the proper shape and crown. If possible, the use of a roller for compaction will greatly improve the finished surface.
This will leave a denser, stronger, smoother surface that will be easier to maintain.
This will cause the gravel to fall apart after the first rain.
15.Severe rutting, loss of crown, gravel loss and deep secondary ditches __________ a combination of any or all of these calls for
major reshaping.
Time to put an asphalt road.
16.Major reshaping often has to be done on the entire cross section and it may have to be done immediately, regardless of the vegetative growth. This requires a much greater effort than routine maintenance. Which one of the following make the job easier.
Motor graders
disks
pulverizer-mixers
rollers
All of the above
17.Which one of the followings causes of corrugation/wash boarding:
The driving habits of people
Lack of moisture
Poor quality of gravel
Lack of crown on the surface
All of the above
18.Washboaring boarding is caused mostly, as a result of driving habits and it is mostly seen where:
Car accelerate or come to a sudden stop
There is a lot of traffic.
19.Figure 10 shows:
The transition from Normal crown to superlevation
Shaping of the gravel work near a bridge
20.The primary maintenance performed on unpaved roads is grading the surface to improve ride-ability and drainage and to remove defects. Other maintenance includes pulling shoulders/ditches, resurfacing/regraveling, and stabilization of the surface
True
False