Freezing of the rolled porridge from reagents, snow and ice leads to the formation of ruts. Ice ledges on the road make a serious difference in driving style, which must be taken into account both when slowly driving in yards and when driving on the highway. Consider how dangerous rutting is, as well as how to drive a car in such conditions as safely as possible.
What is dangerous track
The main danger of rutting on the roads is manifested when driving at an angle. Under such conditions, different resistance is exerted on the wheels, which results in a powerful rotational impulse. If the speed at such a moment was quite high, the car will immediately go into a skid, trying to turn around its axis. In this case, it is difficult even for experienced drivers to react to a sharp change in the behavior of a car. When driving at high speeds on the highway, it is extremely difficult to adequately react and regain control over the car. Earlier we considered, taking the level of adhesion with the road as a more or less constant value. But in the case of a rutted roadway, the behavior of the car is affected not only by the position of the steering wheel and the operation of the pedals, but also by the changing coefficient of adhesion of the wheels to the road surface.
As confirmation of our words, we present a video where you can clearly see how the car goes into a skid after trying to cross the track.
Summer conditions
In the absence of snow cover, rutting on the road occurs due to the pressure of the wheels on the asphalt mixture. Unfortunately, the quality of the structural layers that make up domestic pavement often leaves much to be desired. Despite the fact that in the summer, rutting is much less dangerous for drivers, you should not neglect caution. At high speeds, crossing the track will lead to the buildup of the car, as a result, to the unloading of the car and a change in the balance of the coefficient of adhesion of the wheels to the road.
The ruts pose the greatest danger during rain, as the recesses of the pavement are filled with water. When entering such a zone at high speed, the wheels do not have time to push through the water layer and touch the hard surface. There is an effect of hydroplaning, in which it is extremely difficult to control the vector of movement of a car, since it is almost impossible to guess the direction when driving away in rainy weather.
Rut in winter
Even a novice driver can handle rutting on an icy or snowy road. You just need to follow simple rules:
How to get out of a rut on the road
What to do if you need to get out of the rut? To leave, the swing technique is used:
- slow down to 10-15 km/h. At higher speeds, it is much more difficult to maneuver correctly, in addition, the risk of crossing the car across the roadway increases (the position when the wheels are in the grooves of the track diagonally);
- direct the steering wheel in the direction opposite to the intended place of departure from the track, at the same time slightly pressing the gas;
- as soon as the car jumps a little on the wall of the gutter, release the gas and quickly direct the car towards the exit;
- the resulting impulse will allow the nose of the car to move out of the track, after which you just have to level the car.
At the time of departure, you should not overdo it with gas, because due to slippage, the wheels will lose traction with the road surface and fall back into a rut.
Undermining can be used as an alternative option for overcoming rutting. The point is to use a shovel to cut into the icy edge of the gutter, which will allow the wheel to get the grip it needs to get out. If you feel that you have gone too far with speed and you are starting to turn across the road, release the gas pedal and turn the steering wheel in the direction of the skid. At the same time, it is important to catch the moment when the car is almost leveled, so as not to provoke an impulsive skid in the opposite direction.
Chapter 18
18.1. Assessment of the nature and identification of the causes of rutting
Sections of roads with formed ruts are identified in the process of diagnosing the condition of the roads. At the same time, the depth of the track is measured and the degree of its influence on the speed and traffic safety is assessed, on the basis of which a fundamental decision is made on the need to eliminate it.
Guided by the Classification of work on the repair and maintenance of roads, the type of repair is preliminarily assigned. In order to justify the type of repair and determine the scope and scope of work, it is necessary to identify the causes of rutting in each characteristic area. To do this, it is necessary to carry out detailed surveys of each section of the road on which repair work is planned.
The track is formed as a result of heavy vehicle traffic at high air and pavement temperatures in summer and at high humidity of subgrade soils in spring; insufficient shear resistance of the layers of asphalt concrete pavement or base, as well as soils of the active zone of the subgrade. In this case, abrasion of the top layer of the coating in the rolling strip, additional compaction or reconsolidation of the pavement layers (with or without crushed stone destruction), peeling or chipping of the upper layer, plastic deformation of the pavement layers occur.
The accumulation of residual deformations and structural damage can occur in one or several layers of the road structure at once. The top layer of the coating is located in the zone of maximum temperature effects and perceives the greatest load from the wheels of the vehicle. Therefore, it is subject to deformations to the greatest extent and more often than others is the cause of rutting. Any of the underlying layers can also be the cause of rutting.
The track can be formed as a result of deformation of the transverse profile of the carriageway in the form of recesses along the rolling lanes with or without ridges. The total depth of the track is the sum of the height of the uplift and the depth of the depression (Fig. 18.1).
Rice. 18.1. General view of the outer track: 1 - track base (bottom); 2 - a crest of a rut; 3 - design surface of the coating; IN To- track width; H To- total track depth ( H To =h y +h G);h G- height of the ridge; h y- depth of depression (recess); 4 - lane boundary; 5 - middle of one lane
Field work on the survey of sections with a track is most expedient to be carried out in late summer or early autumn, after the cessation of high summer temperatures. Surveys must be completed at least 6-8 months before the start of the repair. Field surveys are carried out in two stages: visual surveys; instrumental examinations.
A visual inspection of the site is carried out from a car moving at a speed of not more than 20 km / h or on foot. Stops are made in places that require detailed inspection and examination. Inspection of roads with separate carriageways is carried out in forward and reverse directions. At each site determine: the intensity and composition of traffic; coverage condition; roadside condition; condition of drainage structures and subgrade.
The description of the external nature of the track is carried out according to the following criteria: general information; the shape and outline of the edges of the track (pronounced or smoothed); the presence of ridges of vypor and their nature; track depth (small - less than 20 mm, medium 20-40 mm, deep - more than 40 mm); track width; the presence of plastic deformations or signs of abrasion of materials; types of defects on the surface of the coating; heterogeneity of color and quantity of components on the surface (bitumen spots, lack of binder, protrusion of crushed stone, excess sand, etc.); track development dynamics (track develops quickly or slowly); the condition of the coating around the track (a network of cracks, sagging, peeling, etc.); picket position and length of the section with a track (beginning and end of the track), direction of movement and lane number.
A preliminary conclusion on the condition of the road section and the reasons for the formation of a rut is made on the basis of the results of a visual inspection and general data. In conclusion, the planned methods for eliminating the rut are indicated. If the reason for the formation of a rut cannot be unequivocally established during a visual examination, instrumental examinations are prescribed, during which the following are established:
geometrical parameters of the track (depth and width of the track, height and width of the ridges);
geometrical parameters of the road (width of the carriageway, number of traffic lanes and width of each lane, shoulder width, longitudinal and transverse slopes);
evenness of road surfaces;
adhesion of coatings to a car wheel;
pavement strength.
The measurement of the geometric parameters of roads with a gauge by geodetic methods is used at the stage of survey and development of a technical project for road repair (if necessary, milling, leveling layers or widening of the roadway).
In each diameter, 5 points are marked (Fig. 18.2): the edge of the carriageway on both sides TO 1 and K 2 middle of the carriageway WITH 1 and WITH 2 on each side; road axis O.
Rice. 18.2. The layout of the control points on the surface: TO 1 and K 2 - the edge of the carriageway on each side; WITH 1 and WITH 2 - the middle of the carriageway on each side; 1 1 and 1 2 - the bottom of the right track in each lane; 2 1 and 2 2 - the top of the right track; O - axis of the road
The geometric parameters of the road are measured every 10 m along the length of the road. On a road section with a track in the transverse profile, two additional points are obtained that characterize the depth of the track: the bottom of the track (point 1) and the top of the track (point 2). Measurements are carried out along the outer, right track (closer to the roadside) for each lane on which there is a track. The track depth is calculated as the difference between the marks of points 2 and 1.
Elevation marks of additional points 1 and 2 are determined after 20 m, to link the track to the longitudinal and transverse profiles of the road and draw up a milling cartogram or leveling layers. If data on the track depth obtained by other methods are available, the track depth is measured by geodetic methods at least once for every 100 m. In the picket log, the coordinates of the beginning and end of the section with the track are noted.
The assessment of the pavement strength is carried out on sections of the road with a track depth of more than 35 mm or in the presence of a grid of cracks, indicating a possible loss of strength by one or more layers of the pavement. Work is carried out according to the method ODN 218.1.052-2002 spring. To draw up the project, diagnostic data taken from the data bank obtained as a result of previous surveys of this site can be used. Examination of the pavement and pavement is carried out by sampling with rectangular cuttings measuring 300300 mm or by drilling cores with a diameter of 100 mm. It is most advisable to drill samples using a special drilling rig. A breakdown is considered at least two core samples taken at a distance of not more than 0.5 m from one another (two cores - one sample).
Sampling is carried out in order to determine the cause of rutting in the pavement (search for a weak layer) and to assess the possibility of recycling materials.
The sampling depth depends on the type and nature of the track:
with a surface character of the track, the core sampling depth is assigned equal to the thickness of the asphalt concrete layers in the pavement;
with a deep gauge, the core sampling depth is assigned equal to the thickness of the entire pavement. In this case, it is necessary to take soil samples from the active zone of the subgrade.
Recommended sampling locations in one lane are shown in fig. 18.3. Point 1 is located at the bottom of the outer track (closer to the roadside) approximately in the middle of the outer track. Point 2 is 0.2-0.3 m away from the road axis or from the line separating the traffic lanes. Point 3 is located at the top of the upstream ridge. Point 3 is optional. Regardless of the type of track, in each characteristic section, one control sample is taken from point 1 for the entire thickness of the pavement.
Rice. 18.3. Scheme of sampling from the pavement: 1, 2, 3 - places (points) of sampling located in the same alignment, on the same lane
With the surface nature of the track, samples are taken from points 1 and 2. Point 1 is located at the bottom of the outer track, and point 2 is removed from the axis of the road or from the line dividing the traffic lanes by 0.2-0.3 m. ) it is necessary to take two samples (4 cores). The maximum distance between sampling sites along the length of the road is no more than 500 m.
In case of a deep rut, accompanied by extrusion of material from the layer with the formation of upstream ridges, an additional core sample is taken at the highest point of the rut - point 3 (upstream ridge) after 1000 m or one sample for each characteristic section (if the length of the section with a track is less than one kilometer) . The selected samples are tested in 4 stages: they are tested for the destroyed core; each core layer is tested in its natural state; testing reshaped samples of asphalt concrete; determine the properties of mixtures and their components.
Core testing is carried out at the sampling site in a mobile laboratory. In its absence, after visual inspection and marking (sampling location, date of sampling, section, sample and core numbers), the samples are delivered to the laboratory and tested on the day of sampling. If the core could not be taken for the entire depth of the pavement (one or several layers may crumble), it is necessary to collect all the material of the destroyed layer in a separate bag and record the thickness of this layer in the structure (based on the measurement of the layer thickness in the drilled hole).
The thickness of the layer in the structure is measured using a depth probe. In the process of testing unreformed cores, the thickness of the layers is determined based on the results of measuring the thickness at 3 points with an accuracy of 0.5 mm. The arithmetic mean of three measurements is taken as the layer thickness.
The cores are divided into separate layers and determine the adhesion strength between the layers and the average density of the pavement layers in the cores
- average density of the layer in the structure, kg/m 3 ;
m- mass of the sample in air (weighed to the nearest 0.01 g);
V- sample volume (determined by hydrostatic weighing or calculated, m 3.
Then determine the moisture content of the layer in its natural state (with an accuracy of 0.01%) and calculate the water saturation and swelling of the layers. After that, the reshaped samples are tested in accordance with the current regulatory documents.
The material of each layer of asphalt concrete (one sample of 2 cores) is heated in a thermostat and cylindrical samples are made in accordance with clause 6 GOST 12801-98, during testing of which the average density of asphalt concrete is determined; calculate the compaction coefficient of each layer; determine water saturation and swelling of asphalt concrete, compressive strength at temperatures of +50°C, +20°C and 0°C, tensile strength at splitting, tensile strength in bending and deformability indicators, shear resistance characteristics and water resistance. It is allowed to carry out tests by the accelerated method in accordance with GOST 12801-98, item 21.
After testing, the reshaped samples are heated in a thermostat to 80°C, converted into a mixture, and the following are determined: the true density of the mixtures by the pycnometric method, the average density of the mineral part, the porosity of the mineral core and residual porosity, the quality of adhesion of the binder to the mineral part of the asphalt concrete mixture.
The composition of the asphalt concrete mixture is determined and the quality of the constituent components is assessed. To do this, perform the extraction of bitumen from the asphalt mixture. The amount of bitumen in the mixture and the grain composition of the mineral part of the asphalt concrete mixture are determined.
After the end of extraction (extraction of bitumen from the asphalt mixture), the extract (dissolved bitumen) is dried and the components of the mixture are weighed. At the same time, the following are determined: the content of bitumen in the mixture from the coating with an accuracy of 0.1% and the grain composition of the asphalt concrete mixture after extraction.
The quality of the bitumen after extraction from the mixture is determined by the following tests: the depth of penetration of the needle according to the method GOST 11501-78*; extensibility according to the method GOST 11505-75*; softening temperature for the ring and ball according to the method GOST 11506-73*; brittleness temperature according to Fraas according to the method GOST 11507-78*; adhesion of bitumen to marble or sand according to the method GOST 11508-74*.
The quality of crushed stone and sand in the asphalt concrete mixture and structural layers of pavement after extraction is determined in accordance with the requirements of current standards. Compile summary statements of the condition of the pavement and the properties of materials, in which the arithmetic averages of all tested properties are entered.
Analysis of the state of the layers of the road structure. The analysis of the state of the road structure is carried out in four stages. At the first stage, the analysis of the uniformity of the thickness of each layer within the same alignment at points 1, 2 and 3 is carried out. Changes in the thickness of the layers are noted. A layer in which a spread of properties in one section of more than 10% is noted is considered unstable, subject to plastic deformations. Mark the number of the section and the layer in which unstable properties are marked.
At the second stage, an analysis of the uniformity of the properties of the unstable layer along the length of the section is carried out. To do this, evaluate the uniformity of properties in samples of the same name (the bottom of the track or the border of the lanes, or the crest of the track riser) along the length of the section. The homogeneity of properties at the same points along the length of the section confirms the revealed instability or allows one to judge the randomness of the result.
At the third stage, the reasons for the loss of stability of the pavement layers are determined by analyzing the compliance of the properties, pavement layers and their components with the requirements of standards and regulatory documents.
When analyzing the grain composition of mixtures, changes in the composition of mixtures of one section and deviations in composition from the design values are noted. Layers in which crushed stone crushing is noted, or the quality of materials does not meet the requirements of regulatory documents by more than 5%, are considered weak, in need of strengthening or replacement (full or partial).
A list of unstable pavement layers is compiled, in which the location of the section on the road, the number of the layer and the properties by which this layer is recognized as unstable are noted. Make a list of the location of areas whose material is not suitable for reuse.
The final stage of the survey of sections of roads with a track is drawing up a conclusion on the quality of materials in the layers of pavement and their compliance with the requirements of regulatory documents. In conclusion, it is necessary to indicate the places of the track where unstable layers were found, indicate the possible reasons for the loss of stability and the possibility of further operation of the layer in the road structure. It should be noted the possibility of recycling materials of defective layers in pavement and suggest ways to repair a section of the road with a track.
On the basis of the data obtained in the course of field surveys and laboratory tests, the calculation and forecasting of the possible development of rutting is carried out, the results of which make it possible to justify decisions on the method and methods for eliminating the rut.
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RULES FOR DIAGNOSTICS AND ASSESSMENT OF THE CONDITION OF ROADS - MAIN PROVISIONS - ODN 218-0-006-2002 (approved by Order ... Relevant in 2018
4.7. Measuring and evaluating pavement rutting
4.7.1. Measurements of track parameters during the diagnostic process are performed in accordance with the ODM "Methodology for measuring and assessing the operational state of roads by track depth" according to a simplified version using a 2-meter rail and a measuring probe.
Measurements are made along the right outer runway in the forward and reverse directions in areas where the presence of a track is established during visual inspection.
4.7.2. The number of measurement sites and the distance between the sites are taken depending on the length of the independent and measuring sections. A section is considered independent if, according to a visual assessment, the track parameters are approximately the same. The length of such a section can vary from 20 m to several kilometers. An independent section is divided into measuring sections with a length of 100 m each.
If the total length of an independent section is not equal to the whole number of measuring sections of 100 m each, an additional shortened measuring section is allocated. A shortened measuring section is also assigned if the length of the entire independent section is less than 100 m.
4.7.3. At each measuring section, 5 measurement sections are allocated at an equal distance from one another (on a 100-meter section every 20 m), which are assigned numbers from 1 to 5. In this case, the last section of the previous measurement section becomes the first section of the next one and has the number 5 / 1.
The shortened measuring section is also divided into 5 sections, located at an equal distance from one another.
4.7.4. The rail is laid on the protrusions of the outer track and one reading h_k is taken at the point corresponding to the largest depth of the track in each alignment, using a measuring probe installed vertically, with an accuracy of 1 mm; in the absence of bulges, the rail is laid on the carriageway in such a way as to block the measured track.
If there is a coating defect in the measurement section (pothole, crack, etc.), the measurement section can be moved forward or backward up to 0.5 m in order to eliminate the effect of this defect on the read parameter.
4.7.5. The track depth measured in each alignment is recorded in the statement, the form of which with an example of filling is given in Table 4.9.
Table 4.9
TRACK DEPTH MEASUREMENT SHEET
| Independent site number | Binding to mileage and length | Measuring section length l, m | Depth of rut on alignments | Estimated track depth h_kn, mm | Average estimated track depth h_ks, mm | |
| line number | track depth h_k, mm | |||||
| 1 | from km 20+150 to km 20+380, L = 230 m | 100 | 1 | 11 | 13 | |
| 2 | 8 | |||||
| 3 | 12 | |||||
| 4 | 17 | |||||
| 5/1 | 13 | |||||
| 100 | 2 | 16 | 13 | 12,7 | ||
| 3 | 10 | |||||
| 4 | 13 | |||||
| 5/1 | 11 | |||||
| 30 | 2 | 9 | 12 | |||
| 3 | 14 | |||||
| 4 | 12 | |||||
| 5 | 7 | |||||
For each measuring section, the estimated track depth is determined. To do this, analyze the results of measurements in 5 sections of the measuring section, discard the largest value, and the value of the rut depth following it in the descending row is taken as calculated at this measuring section (h_KN).
4.7.6. The calculated rut depth for an independent section is determined as the arithmetic mean of all values of the calculated rut depth in the measuring sections:
| , mm. | (4.1) |
4.7.7. The assessment of the operational state of roads in terms of track depth is carried out for each independent section by comparing the average estimated track depth h_KS with the allowable and maximum allowable values (Table 4.10).
Table 4.10
Scale for assessing the condition of roads by track parameters measured using a simplified method
| Estimated speed, km/h | Track depth, mm | |
| admissible | maximum allowable | |
| >120 | 4 | 20 |
| 120 | 7 | 20 |
| 100 | 12 | 20 |
| 80 | 25 | 30 |
| 60 and under | 30 | 35 |
Road sections with a rut depth greater than the maximum allowable values are considered dangerous for vehicle traffic and require immediate work to eliminate the rut.
What causes ruts on asphalt? Many motorists believe that the main reason is studded tires. Let's talk about the main points of the formation of ruts on roads. Who is guilty?
Main reasons
If you completely prohibit the operation of cars with studded tires, this will not eliminate the appearance of ruts on the roads. But why thorns are considered the main source, because there are other reasons. Tracks from studded tires are in the form of narrow strips. And from freight transport and a large flow of cars - in the form of deformation of the roadway. As a result, wide depressions appear on the roads, with elevated edges.
Namely, this type of track is most common. And the destruction from studded tires, compared with the deformation from a large flow of cars, is minimal.
It turns out that the important reasons for the appearance of the track are the imperfection of road construction works and the poor quality of the asphalt concrete mixture. According to the technical requirements, the roadway should consist of two layers, each of which must be left alone for three days. It often happens the other way around - the road builders will lay only one layer of asphalt, which is able to withstand the load of only 300 cars a day. And where can you find such roads in a large city with such low traffic?
In addition, when applying each layer of asphalt, it must be allowed to dry for 72 hours. In our country, everything is done the other way around, as soon as asphalt is laid, a stream of cars will immediately be allowed to pass through it. And who does not mind, from motorists, "fly" on the new smooth asphalt with a breeze.
Another reason for imperfection
When repairing an old road with deep ruts, only the top layer of asphalt is often removed, and a new one is applied in its place. This is certainly cheaper than building it again, but it's of little use. After a while, ruts form again.
When a rut is formed, the entire roadbed is deformed. To get rid of them, you need to rebuild the road anew, and not just replace the top layer. By the way, in Europe, the surface repair of the road, because. little sense from him.
It is clear that the main reason for the formation of a rut is the poor quality of the roadway and road works. Their contribution to the destruction of asphalt is minimal against the background of exposure to cold, heat, wind, heavy trucks. Of greater importance is the quality work of builders. If done correctly, a smooth and even road surface will delight drivers for decades. But, many motorists continue to argue that the spikes on the wheels are to blame. And often, they refer to the European experience.
Studded tires have been banned in Germany since 1975, but this is not related to road destruction. The reason for the ban is a longer braking distance car with studded tires on dry pavement.
Can bad roads be redone?
The layout of the streets of large cities and the heavy workload will lead to the fact that during the overhaul, entire areas will be covered by a transport collapse. Cutting and replacing the upper damaged layer does not give the desired effect, because the deformation of the coating as a whole occurs, and not just the few centimeters removed. A year will pass, and the new surface will show the defects of the old one. For example, in Europe such a scheme is not applied. If the road needs repair, it is completely closed. It costs more, but the result is more profitable ...
When restoring damaged pavement, rough asphalt is used. It has a longer service life, which means it needs less repair. But the noise from it is above average. When repairing, bypass technologies are used when the top layer is laid from gravel. Motorists themselves must "roll" it. In practice, this turns around, in the first days after the repair, with the departure of stones from under the tires, which often leads to chips on the glass.
In order for the road to last longer, all construction technologies must be observed. But the spikes in the destruction of asphalt are definitely not to blame ... The track is the result of non-compliance with the laying technology.
Administrator,Of course, every motorist has at least once encountered the problem of rutting on the roads: when driving along some highways, you can notice characteristic wheel marks in the form of crushed asphalt, which can stretch for many, many kilometers. Rutting is a fairly common phenomenon that not only makes traffic difficult, but also spoils the appearance of the road, and is also a very dangerous accident rate factor, which is why it is important to know about the real causes of rutting and how to deal with it.
Pavement structure
Modern roads, especially highways with active traffic, are built from several structural layers, which are called pavement. Road pavement is a reinforced subgrade surface on which vehicles directly move.
Pavement usually consists of the following structural layers:
- Coating- this is the top layer of the pavement, which should be the most durable, since it is in direct contact with the wheels.
- Base
- Additional (leveling) layer- this layer is designed for additional leveling of the canvas, drainage and protection against freezing.
The type of pavement directly depends on the purpose of the road: for example, profiled dirt roads are created with just one layer of high-quality soil, since they are usually used in rural areas where there is little traffic. Highways of cities and large metropolitan areas, as well as federal highways, require a completely different approach, since every day they experience a huge load from vehicles passing through them - cars and trucks.
Reasons for rutting
Since the pavement consists of several structural layers, each of them significantly affects the strength and rigidity of the roadway, and, consequently, the ability of the road to withstand long-term loads.
Usually, for highways and highways with active traffic, asphalt concrete or cement concrete pavement is used. At the same time, rutting can occur only on roads with asphalt concrete pavement, since, despite its strength and low wear, it is still much less rigid than cement concrete pavement.
Asphalt pavement is usually very durable and, once cured, is difficult to deform. However, if the coating is laid on a not very strong base, which begins to sag and mix with an additional "drainage" layer, this gradually leads to the formation of a rut on the road.
So, the main reason for the rut- this is the insufficient density of the lower structural layers of the roadway (base and additional layer), which contributes to the mixing of layers and leads to subsidence of the road surface.
Rutting methods
Obviously, subsidence of the road surface can be avoided by strengthening the lower structural layers.
Often, asphalt concrete is used as the base of the roadway, but this does not always solve the problem of rutting, since the softer lower layers inevitably sag.
Modern geosynthetic materials - geogrids and geogrids - perfectly solve the problem of rutting. Biaxial geogrids and reinforcing polymer geogrids look like mesh flexible sheets of polymer fibers that are used as a lining for the soil and significantly increase its strength.
Geosynthetics are widely used for the following purposes:
- Strengthening slopes, slopes and banks
- Construction of parking lots, helipads
- Retaining wall installation
- Strengthening of pavement bases, reinforcement of weak soils in road construction
If during the construction of a road a flat reinforcing geogrid is used as an additional layer, this will help to avoid rutting even with constant serious dynamic and static loads on the road.
