Impact of the Social Law on Truck Parking Sustainability in the EU

: Road freight transport in its current form has signiﬁcant issues in terms of sustainability. These problems arise from an increase in density as well as from legislative decisions. Although not obvious, the parking of freight vehicles and legislation are connected. EU legislative decisions have reduced the sustainability of the parking system. The ﬁrst and main goal of our study was to test the hypothesis that social law requirements negatively impact truck parking. The second important goal was to create a methodology that can determine the necessary number of parking spaces that comply with the requirements of social law. The method used for this research included the counting and numbering of parking spaces on speciﬁc routes in the EU compared with the intensity of freight vehicles on these routes. Our study shows that it is not possible to meet the requirements of social law and that the current state of freight vehicle parking is unsustainable. Planning sustainable parking areas in accordance with regulatory requirements is necessary, otherwise drivers will circumvent the rules, leading to a distortion of the freight transport market. In this paper, we also outline the proposed methodology for numbering parking spaces in a speciﬁc


Introduction
In terms of inland freight transport, road freight transport is currently the most significant mode of transportation. According to The White Paper on Transport, transport is supposed to increase by 80% in 2050 compared to 2010. So far, this seems to be accurate, as the number of vehicles utilizing public infrastructure has increased as expected. With the increasing number of vehicles, especially freight vehicles, it is necessary to build infrastructure that meets increased demand for capacity and car parking. The number of cars parking influences the safety and sustainability of transport because it is connected to safety breaks and ensuring drivers' rest. Increasing driver demands for rest also increases demands on parking places (e.g., judgment [1]). In this study, we aimed to determine whether the infrastructure of car parks is sustainable following the increase of road freight transport in the European Union. We specifically investigated the drivers of road freight transport. We analyzed the possibilities of vehicle parking in the selected area. Because goods transport is a significant aspect of the economic increase, we dealt with transport output sustainability in connection to parking policy; therefore, we processed the proposals of the European Union parking insurance sustainability. The contribution of our research is a draft of solutions, through which it will be possible to aim for vehicle parking sustainability that is related to the social regulation demands.
Only a few studies have been interested in the relation between road transport output sustainability and truck parking place capacity. Chatterjee and Wegmann in 2000 [2] noted that in the United States, there are parking places for trucks in public car parks and resting areas along highways, but in the state of Tennessee, some car parks were fully occupied, causing big trucks to park on highway feeders to these areas. Based on interviews with drivers, they found that, although there are existing facilities for resting and sleeping in public places, many truck drivers cannot use these facilities due to a lack of available parking spaces, particularly during the night. Al-Kaisy et al. in 2012 [3] showed that the existing studies about rest areas were not accurate, or that they came from old data. Data were collected from surveillance video cameras with views of a whole parking place in 44 car parks in the USA over one week. We found that the average trucks' parking time is longer than personal cars' average parking time on less occupied highways [4]-that means an average of 30 min during a day and approximately 3 h and 22 min during a night. Kay (2014) introduced the results of binary logistics regression and negative binomial regression on demand characteristics of 47 road-resting places in Michigan [5]. He found out that as the distance between resting areas increased, the number of cars occupying the road resting areas increased. He used online data obtained from the monitoring information transport system from Michigan's transport department.
The problem of car park capacity was dealt with in Japan by Muramatsu and Oguchi in a 2017 study [6]. From the results of this study, it is possible to claim that parking places for freight transport are under-utilized in Japan. The authors suggest implementing a time toll to motivate the drivers to use a public area of the car park in as short a time as possible. This kind of approach is counterproductive to the requirements of road transport safety. The stated claim is possible to support using study results processed by author Jung in 2017 [7]. A study on the conditions in Korea showed that complementing resting areas, which are relatively small resting areas between common resting areas and which serve mainly for drowsy drivers' rest, could decrease the number of accidents caused by sleepiness by approximately 14%, particularly on highways with two or more driving lanes. Matsushita et al. surveyed resting area distributions and developed a model of selection and model of attractivity evaluation [8]. Their results showed that transport time, area attractivity, and the number of passengers over 65 positively increases car park selection, while the available areas, cleanliness of sanitary facilities, and availability of restaurants or shops increases attractivity evaluation. Their results also emphasize the importance of the information provided concerning the resting areas and nearby relaxing places. A study of Hajime Seya examines truck drivers' behavior in car parks [9]. The author uses six-month data about the vehicle's trajectory from the digital tachograph and introduces a car park solution and, parallelly, a situation by multilevel continual model development. Given that digital tachographs note trucks' time and area information in Japan, it is possible to analyze not only the behavior in car parks, but also a way to measure parking time. In this study, data was sourced from 1600 vehicles equipped with tachographs, similar to those used in the European Union. Based on data from digital tachographs, it was possible to identify an average driver's resting time, but was not possible to identify a parking place occupancy.
For truck drivers, it is important to know up-to-date information about free parking spaces. Nowadays, accurate GPS devices are used for navigation, but there is no guarantee of a free parking space. After finding out that the driver cannot park the vehicle in a given place, they begin to experience time-related stress; therefore, increasing the available information regarding parking spaces is important, which must be based on real-time parking data. According to [10], the parking information system can count the number of vehicles' arrival and departure. This is called real-time indirect parking monitoring [11]. Indirect methodologies are based on detecting and classifying vehicles at all ingress and egress points of the parking facility and summing the difference over accumulated counts at specified time intervals, as opposed to directly monitoring each parking space status. Then, the data are sent to local parking information processing or management centers, or regional traffic management centers via communication networks. The information must be processed and converted to form, which navigation devices in vehicles can then display. This procedure has four steps: Data collection, data process, information and communication management, and the last is information display. Another source [12] talks not only about capacity information, but also about the possibility of preliminary parking place booking. The source [13] describes an online GIS (Geographic information system) survey instrument that is used for collecting the location information of areas with truck parking capacity shortages. According to [14], the parking pattern is defined by one main parameter-the global demand-to-supply ratio. In reality, the spatial distributions of the demand and supply are essentially heterogeneous, and this heterogeneity is critical for transportation management and planning.
According to the analyses processed by Andras Nowak, more than 30,000 parking places in Germany are missing [15]. On average, 7000 trucks park in restricted places like highways feeders and exits and emergency parking areas on highways. They block approaches to gas stations or are in parking spaces defined for personal car parking. Another study [15] points out that, from 2016, the number of injuries and collisions with trucks has continually increased because of incorrect parking. In Germany, the listed state causes problems with finding drivers that are willing to drive a vehicle for longer distances like 500 km. More than 15% of all drivers spend the night next to the highway with no comfort, no toilets, or the possibility to wash [16]. According to studies [15], the increase of road freight transport in Germany introduces an extra 4% per year that requires 4000 freight transport parking places that are currently unavailable. Problems with the establishment of parking places next to highways also have an economic aspect. According to [17], the building of parking areas is very uneconomic because the investment cost for one parking place is 70,000-120,000€.
Based on the analysis, it is possible to claim that road freight transport output increasing and demands in social areas cause problems with trucks parking. The capacity of resting areas is not built together with road freight transport output development.
International road transport operation in member states of the European Union requires social regulation compliance, especially Regulation (EC) No. 561/2006 on the harmonization of certain social legislation relating to road transport. These requirements are shown in Table 1. Table 1. Requirements for the work regime of drivers in the EU. Source: [18], processed by authors. Minimum length of daily rest (during 24 h) 11 h (possible to reduce into 9 h triple per week. The rest is possible to divide into 2 intervals within a 24 h period; first part has to be at least 3 h, and the second part at least 9 h) Minimum length of weekly rest 45 h, which could be reduced into 24 h; however, the reduction shall be compensated before the end of the third week following the week in question. A weekly rest period that falls in two weeks may be counted in either week, but not in both.

Regime of Work Requirement
The following maximum marginal time intervals are defined in member states of the EU: Maximum continuous vehicle driving time, maximum daily vehicle driving time, maximum weekly vehicle driving time, maximum two-weekly vehicle driving time, and the maximum number of work shifts that follow each other.
Minimum marginal times are defined as: Minimum length of work-rest after 4.5 h of driving, the minimum length of daily rest and limited time of its latest end, and the minimum length of weekly rest. Table 2 shows a comparison of truck driver requirements in the USA, Canada, and New Zealand. In the United States, there are defined driving times and resting times outlined in the Federal Motor Carrier Safety Regulations. In Canada, the social problem concerning drivers working in road transport is defined in the National Safety Code Standards-Standard 9 [19]. In New Zealand, the working regime for drivers is outlined in the Land Transport Regulations and Land Transport Act: Part 4B, Work Time and Logbooks [20]. The analysis shows that, during vehicle operation in EU countries and contracting states of the AETR (Accord Européen sur les Transports Routiers, the European Agreement Concerning the Work of Crews of Vehicles Engaged in International Road Transport), it is possible to realize the lowest performance per week and also for the two following weeks. In the EU, the driver is allowed to utilize the maximum 90 h of vehicle driving once every two weeks; in other states, the minimum is 120 h; in the USA, 140 h can be driven before the week restart, for New Zealand, the minimum is 166 h. Table 2 shows a comparison between these countries.
A vehicle that is in the EU and driven by one driver has a shorter driving time per two weeks ( Table 3) when compared to other chosen countries. If vehicles in the EU spend a significantly longer time in parking areas, it is necessary to build a higher number of parking places for the same number of vehicles than in other countries. This means that, in the current conditions of the EU, investigating the other countries compared will not yield any meaningful solution to the problem of parking for freight transport.

Materials and Methods
The authors' team realized from October 2018 to March 2019 an extensive research of drivers' skills in road freight transport with vehicle parking. As part of the research at the University of Žilina, a Google questionnaire was compiled and published on internet discussion forums that are used by drivers of international road freight transport. Any driver who visits these discussion forums could answer. Drivers from Slovakia, Poland, Bohemia, and Germany were the main responders-all provide international road transport. The survey was taken by 825 drivers, from which 6% provide transportation by vehicles with a combined total weight of 40 tons. Considering the study in [22], our survey showed that drivers' quality of sleep is better at night, and we attempted to determine whether the drivers have a problem with rest due to a lack of parking places in night hours. Out of the responses, 86.67% of drivers answered that they have a problem finding parking. Most often, they have a problem finding a parking place by highways, followed by main roads and border crossings; drivers said they can find a parking place in industrial areas the easiest. Drivers, according to social demands [23,24], can drive a vehicle no more than 9 h, then must have a daily rest of at least 11 h. Excluding a daily rest, the drivers have to have working breaks after a maximum of 4.5 h of driving. The length of the break is, at minimum, 45 min. This means that every truck has to stop in a car park after 4.5 h of driving at the latest. The authors also analyzed how the drivers plan their rest. Our research shows that drivers often cannot drive the whole 9 h per day or 4.5 h without break, because they are afraid that they will not be able to find a car park. Drivers' answers were often: I park the vehicle earlier or start driving earlier only because of finding a free place.

Results
The survey showed that 92% of drivers adjust the driving time and their own working time to the situation in car parks. As a result, the listed drivers are not using their working time effectively because they cannot rely on finding a safe parking place at the end of their working time. Our research was also aimed at the comfort of drivers during the rest in the car park. From the point of view of safety, only 12.73% of drivers feel safe in a vehicle during rest. Almost half of the drivers (49.45%) stated that they are afraid of fuel and personal theft from the vehicle, 14.3% sometimes feel endangered, and 23.5% of drivers have been robbed in a car park. Our research gathered a lot of data. The most important results relevant to this paper are displayed in Tables 4 and 5. The survey involved 65.3% of international freight drivers, 27% of national freight drivers, and 7.7% of drivers who perform both modes of transport. Despite the clear lack of parking space, our research also dealt with car park facilities. A significant amount of car parks does not provide suitable comfort for drivers. Based on the results, drivers require more facilities and safety measures to improve the quality of the rest period, whose length is more than 11 h. The results are listed in Table 5. The most important demand is the cleanness of toilets and showers. Based on our research, it is possible to claim that sufficient capacity for freight transport parking does not currently exist. This situation gets worse with the increasing output of road freight transport. Despite significant efforts of logistic companies and public institutions, the output cannot be moved to other transport modes [25], and in the close future, it is not possible to consider autonomous trucks in road traffic. Based on our research, it is possible to claim that, from the point of view of sustainability, parking policy is important. Currently, 87% of drivers report that they do not feel safe in car parks, 87% of drivers have problems with vehicle parking, and 92% of drivers adjust their working time to deal with the limited parking spaces and poor facilities. Without a parking policy solution, and with freight transport output increasing, it is reasonable to assume that drivers will search for parking places near highway exits to urban areas to find comfort and to avoid congestion and undesirable conditions.

The Ban on Spending Weekly Rest in the Vehicle
If the vehicle is equipped with a suitable sleeping device for each driver and the vehicle is stationary according to Art. 8 Regulation No. 561/2006 [22], the driver may take a daily rest period and a reduced weekly rest period in the vehicle. Until 2014, this condition did not generally apply in practice. Belgium and France adjusted the fines in 2014. The driver could not spend their regular weekly rest in the vehicle; however, if they do so in Belgium, they could get a fine of up to €1800. From 11 July 2014, the fine increased to a maximum of € 30,000, or imprisonment of one year in France [26,27].
The Court of Justice of the European Union also expressed a judgment on the issue of regular weekly rest on 20 December 2017. In the judgment, the court ruled that drivers of freight transport could not spend regular weekly rest in vehicles. This also means that no EU country can interpret legislation differently [28]. The dragging litigation began three years ago when the Belgian transport company Vaditrans BVBA initiated a dispute with the Kingdom of Belgium. The carrier considered that regular weekly rest could not be penalized because Regulation (EC) 561/2006 did not provide for such a prohibition in its provisions. Article 8 (8) of Regulation (EC) No 561/2006 states: "If the driver so decides, daily rest periods and reduced weekly rest periods may be taken outside the base, as long as he has suitable sleeping places for each driver and the vehicle is stationary." The Belgian authorities referred to the wording of Regulation (EC) No 561/2006. They asked for clarification on whether this provision of Regulation (EC) No 561/2006 is to be interpreted as meaning that it contains an implicit prohibition on the use of regular weekly rest in the vehicle.
As EU law can only be enforced by an EU court, a Belgian court has asked an EU court to determine whether EU law contained an implicit ban on the use of weekly rest in a vehicle [29,30]. The Court of Justice of the EU has stated that EU law only concerns the possibility of reducing the weekly rest period by 24 h, which is allowed in the vehicle in certain circumstances; however, it follows that it should not apply to regular 45 h rest. If possible, the driver may spend the rest of the time in the vehicle, but this would not improve the driver's working conditions, as required by EU law.
Following the judgment, the Court of Justice of the European Union explicitly prohibits drivers from spending their regular weekly rest in the vehicle. The judgment is valid from the date of publication and is valid from 20 December 2017. It is important to note that the judgment is valid in all EU Member States. It follows that, if national law allows a driver to impose a fine for such an offense, the inspection body may also impose such a fine [31]; however, the judgment does not regulate the power to control the use of taking regular weekly rests on the territory of a particular Member State. The judgment only stipulates that drivers in a vehicle may not take regular weekly rests. This means that, for example, in Belgium, if the inspection authorities find that a Slovak driver driving for a Slovak hauler takes a regular weekly rest period in Germany, they may be given a restrictive fine in Germany when inspected in Belgium. It is important to note that the regular weekly rest area can be found from the digital tachograph (from the previous 28 days) or the driver card. For this reason, drivers entering the country of arrival and the country of exit should carefully set the country code on the digital tachograph [27].
The amount of the fines is currently set under the national law of each EU Member State. It will take some time for a fine to be added to national rules for spending regular weekly rest in the vehicle in all countries. From 1 January 2017, Regulation (EU) 2016/403 updated the classification of serious road traffic offenses in the EU; however, the regulation does not cover a breach of the rule of taking regular Sustainability 2020, 12, 9430 7 of 16 weekly rests in a vehicle. According to that classification, each Member State has adopted national legislation providing for penalties in the field of road transport.

Transport Planning in the EU in Relation to Taking Weekly Rest Outside the Vehicle
The Court's judgment points to several problems with the ban on weekly rest periods. Trucks must park in designated truck parking lots. These car parks are usually out of town and do not have motels or hotels nearby [32]. In connection with the problem of weekly rest, three transport routes leading from the Slovak Republic to selected EU countries were processed.
The routes we studied head west from the Slovak Republic because more than 80% of transport from the Slovak Republic goes west. We have also chosen one route to the north, one direct to France, and one to the south. Subsequently, parking lots for trucks were searched-specifically, parking lots that provide the driver with the opportunity to stay in case of taking a regular weekly rest. Truck parking spaces were searched using the Truck Parking Europe application, which provides information on the possibility of parking on a given route with a maximum vehicle detour of 12 km. After searching for accommodation facilities, the accommodation capacity was also ascertained. In some cases, this information was not available. Based on individual capacities, accommodation can be divided according to the number of rooms into the following three categories [27]: (a) Small (1 to 20 rooms), (b) medium (21 to 40 rooms), and (c) large (more than 40 rooms). Figure 1 shows the first routes leading from Žilina in Slovakia to Lyon in France. The total length of the route is 1449 km. There are 201 car parks or rest areas on this route, but only 16 car parks offer accommodation. Up to 50% of the sought-after car parks, which provide accommodation for drivers on the given route, are located in Switzerland. Another example is the Slovak Republic. In this country, no such car parks were found on the selected route after evaluation using the application. Table 6 also contains information about accommodation capacity. Most of them can be classified in the middle category (21-40 rooms). Accommodation with a capacity of more than 40 rooms is provided by only 4 accommodation facilities out of 13 found. national legislation providing for penalties in the field of road transport.

Transport Planning in the EU in Relation to Taking Weekly Rest outside the Vehicle
The Court's judgment points to several problems with the ban on weekly rest periods. Trucks must park in designated truck parking lots. These car parks are usually out of town and do not have motels or hotels nearby [32]. In connection with the problem of weekly rest, three transport routes leading from the Slovak Republic to selected EU countries were processed.
The routes we studied head west from the Slovak Republic because more than 80% of transport from the Slovak Republic goes west. We have also chosen one route to the north, one direct to France, and one to the south. Subsequently, parking lots for trucks were searched-specifically, parking lots that provide the driver with the opportunity to stay in case of taking a regular weekly rest. Truck parking spaces were searched using the Truck Parking Europe application, which provides information on the possibility of parking on a given route with a maximum vehicle detour of 12 km. After searching for accommodation facilities, the accommodation capacity was also ascertained. In some cases, this information was not available. Based on individual capacities, accommodation can be divided according to the number of rooms into the following three categories [27]:  Figure 1 shows the first routes leading from Žilina in Slovakia to Lyon in France. The total length of the route is 1449 km. There are 201 car parks or rest areas on this route, but only 16 car parks offer accommodation. Up to 50% of the sought-after car parks, which provide accommodation for drivers on the given route, are located in Switzerland. Another example is the Slovak Republic. In this country, no such car parks were found on the selected route after evaluation using the application. Table 6 also contains information about accommodation capacity. Most of them can be classified in the middle category (21-40 rooms). Accommodation with a capacity of more than 40 rooms is provided by only 4 accommodation facilities out of 13 found.    Figure 2 shows the second route leading from Slovakia (Žilina) to Hamburg (Hamburg). There are 145 car parks on this route, but the driver can take their regular weekly rest in only 15 of them ( Table 7). Most of the parking lots for trucks on this route provide accommodation in Poland, specifically 9 out of 15 and at least in the Slovak Republic. It should be noted that the transport route within the Slovak Republic is only 39 km long out of a total of 1048 km. Information on accommodation capacity was available only in eight cases. Of these, four have a capacity of fewer than 20 rooms, and only one accommodation has more than 40 rooms.

Germany
Irschenberg . Most of the parking lots for trucks on this route provide accommodation in Pol ically 9 out of 15 and at least in the Slovak Republic. It should be noted that the transport r the Slovak Republic is only 39 km long out of a total of 1048 km. Information modation capacity was available only in eight cases. Of these, four have a capacity of f 0 rooms, and only one accommodation has more than 40 rooms.   The last analyzed route, which is shown in Figure 3, was the route leading from the Slovak Republic (Žilina) to Italy (Livorno). There is a total of 113 car parks on this route, and only 15 of them also provide accommodation. The route includes three countries-Slovakia, Austria, and Italy. This route includes seven truck car parks in Austria (Table 8) and eight in Italy (three car parks are nearby and also provide the same type of accommodation). The capacity of facilities was only found in 13 cases. The best options for drivers are provided by car parks in Italy, which in most cases provide accommodation with a capacity of more than 40 rooms.

Poland
Oleśnica he last analyzed route, which is shown in Figure 3, was the route leading from the Sl blic (Žilina) to Italy (Livorno). There is a total of 113 car parks on this route, and only 15 of rovide accommodation. The route includes three countries-Slovakia, Austria, and Italy. includes seven truck car parks in Austria (Table 8) and eight in Italy (three car parks are ne lso provide the same type of accommodation). The capacity of facilities was only found . The best options for drivers are provided by car parks in Italy, which in most cases pro modation with a capacity of more than 40 rooms.    Table 9 represents a comparison of the individual routes concerning the number of truck parking lots. On the Žilina-Lyon line, there are 8% of truck parking lots with accommodation from the total number of truck parking lots on this route. There are 10% of car parks on the Žilina-Hamburg route and 13% of the total on the Žilina-Livorno route. From the analysis of the processing of information on truck car parks that provide accommodation for the driver, we confirmed that truck car parks generally do not have motels or hotels in their vicinity. Many accommodations are located in the city [27]; however, parking trucks are not allowed in the cities, and drivers would somehow have to get to the nearest accommodation facility. If the vehicle is parked in an unsecured truck parking lot, there is a risk to the goods being transported. If the truck parking lots are not guarded, there is a risk of possible damage to the transported goods or theft not only of the goods, but also of the entire vehicle. When planning the transport, it is necessary to take into account, in addition to the provision of suitable parking lots for trucks, the current capacity of the accommodation. This is because some accommodations provide a relatively low number of rooms.
A ban on regular weekly rests in the vehicle can interfere with some important transport routes. This may also affect the transport companies themselves operating in the Western European market, which carry out sabotage operations and for longer periods, drivers operate outside the company's premises.

Proposal to Increase the Capacity of Freight Transport Car Parks
Most research teams, e.g., teams in Germany, deal with increasing car park capacity by its enlargement or by building a new car park based on road freight transport vehicles intensity in the road network. A need for parking places in a specified section depends not only on transport intensity, but also on the length of stay of vehicles in the car park [28]. Ordinary daily rest in EU and contracting states of AETR (e.g., Russia) is at least 11 h, as well as at least one break of a duration of 45 min after 4.5 h of driving [23]. This means that a vehicle, during 24 h, can drive no more than 12 h and 15 min. A certain number of parking spaces also depends on the freight transport vehicle speed, which, based on research, is 60-80 km per hour [33]. The number of required parking places in a specified section of highway or road is possible to be defined by relation (1). This equation is used to calculate parking spaces regardless of the type of park area.
where PP-needed number of parking places, I-traffic intensity in solved section, R/24-driver's rest in hours/24 h, D-length of the solved section, S-the average speed of truck in solved section, and T d -the average driving time of vehicle per 24 h. The proposed equation mathematically defines the number of parking spaces. Its reliability depends on the accuracy of input data. It takes into account traffic intensity in the solved section, its length, the average speed of trucks, and also basic data about the rest period of truck drivers. Although it is not calibrated, it still provides a theoretical basis for designing new parking areas.
After the application of the introduced relationship into selected sections of roads of European importance in Slovakia, it is not possible to claim that car parks achieve the demanded capacity in any section (Table 10). The intensity data in Table 10 are sourced from Road Databank, which is available online. Road Databank is managed by the department of Slovak Road Administration, which is responsible for the operation of the Central technical Register of Roads, determination of Abnormal Transport Routes, and operation of the Traffic Information Centre. Despite that analyzed car parks in individual sections do not achieve the demanded capacity, the results of the survey confirm that it is possible to increase the capacity of existing car places by effective management.

Return Allowing Car Park
Two solutions improve the management and comfort in car parks, and, when implemented together, partly decrease the demands on built-up areas by parking places. These solutions are shown in Figure 4. Two solutions improve the management and comfort in car parks, and, when implemented together, partly decrease the demands on built-up areas by parking places. These solutions are shown in Figure 4. The first solution is to allow the return of the vehicle. Currently, the vast majority of car parks do not allow vehicles to return. If a vehicle searches for a free parking place, it only drives through one line, and if it cannot find a free place there, due to the layout and direction of traffic, it has to abandon the car park even when there are free lots in another line. There is a possibility to reverse at the beginning, but it is very difficult, tedious, and dangerous in a crowded car park. The driver has no certainty of success because after coming to the next vehicle, the driver is forced to leave the car The first solution is to allow the return of the vehicle. Currently, the vast majority of car parks do not allow vehicles to return. If a vehicle searches for a free parking place, it only drives through one line, and if it cannot find a free place there, due to the layout and direction of traffic, it has to abandon the car park even when there are free lots in another line. There is a possibility to reverse at the beginning, but it is very difficult, tedious, and dangerous in a crowded car park. The driver has no certainty of success because after coming to the next vehicle, the driver is forced to leave the car park. The proposal contains a car park where the bi-directional traffic is possible, that means after the unsuccessful searching of a free parking place, a vehicle can return to the beginning and try to find a free place in another parking line.
The second solution is a parking organization method where vehicles reverse into a parking place. When a parking place is occupied, other vehicles park longitudinally behind parking places. Of course, earlier parked vehicles abandon the parking place earlier and longitudinally parked vehicles block an approach to the parking place (Figure 4-vehicles 4 and 5). In this case, the vehicles have to reverse into parking places too many times with right-hand cornering, when the driver has a severely limited view in a rearview mirror, because if the articulated semi-trailer corners to the right-side with a bigger angle, the driver cannot see the end of a semi-trailer in the right mirror, as he sees only right side of the semi-trailer, and in a left mirror, he sees only the front of the trailer ( Figure 5). park. The proposal contains a car park where the bi-directional traffic is possible, that means after the unsuccessful searching of a free parking place, a vehicle can return to the beginning and try to find a free place in another parking line. The second solution is a parking organization method where vehicles reverse into a parking place. When a parking place is occupied, other vehicles park longitudinally behind parking places. Of course, earlier parked vehicles abandon the parking place earlier and longitudinally parked vehicles block an approach to the parking place (Figure 4-vehicles 4 and 5). In this case, the vehicles have to reverse into parking places too many times with right-hand cornering, when the driver has a severely limited view in a rearview mirror, because if the articulated semi-trailer corners to the rightside with a bigger angle, the driver cannot see the end of a semi-trailer in the right mirror, as he sees only right side of the semi-trailer, and in a left mirror, he sees only the front of the trailer ( Figure 5). This proposal suggests that vehicles reverse into parking places with left-handed cornering as, although the driver, after cornering, has a limited view in the right rearview mirror where they see only the front of the trailer, they also see the left side of the road train in the mirror and after cornering, they see the whole of semi-trailer from a side driver's window with a bigger angle. Reversing to the left side is more comfortable and safer for the driver. This solution is more economical for a built-up area where there is no demand on the road behind the first parking line, or between the second and third parking line. A fourth park line is visible only for the reason of showing the blocking by longitudinal parking (Figure 4). The first parking line is proposed according to the response of drivers from the transport survey, who suggested that vehicles should be arranged to keep the driver's cab away from the highway, to lower noise and increase the rest comfort of the driver; however, turning the driver's cab does not sufficiently eliminate noise, especially in an empty car park, so it is necessary to build a noise barrier behind the first line. Additionally, it is necessary to build a visual barrier This proposal suggests that vehicles reverse into parking places with left-handed cornering as, although the driver, after cornering, has a limited view in the right rearview mirror where they see only the front of the trailer, they also see the left side of the road train in the mirror and after cornering, they see the whole of semi-trailer from a side driver's window with a bigger angle. Reversing to the left side is more comfortable and safer for the driver. This solution is more economical for a built-up area where there is no demand on the road behind the first parking line, or between the second and third parking line. A fourth park line is visible only for the reason of showing the blocking by longitudinal parking (Figure 4). The first parking line is proposed according to the response of drivers from the transport survey, who suggested that vehicles should be arranged to keep the driver's cab away from the highway, to lower noise and increase the rest comfort of the driver; however, turning the driver's cab does not sufficiently eliminate noise, especially in an empty car park, so it is necessary to build a noise barrier behind the first line. Additionally, it is necessary to build a visual barrier between lines 2 and 3 so that vehicles do not bump into each other. An example of this parking management is as follows: Vehicle 1, after entering the car park, parks by reversing into a free place in the first line. Vehicle 2 drives through parking line 3 where it could not find a suitable place, but does not have to abandon the car park. It comes back onto the road between the first and second lines and parks in the second line by reversing. Vehicle number 3 fails to park in the third line, but even in the second line could not find a possible place. It is up to the driver whether they choose to turn to the petrol station and park by left-handed reversing, or park in the first line by driving forward under more demanding conditions, driving by reversing to the right side.

Car Parking Using Intelligent Transportation Systems
The second proposal concerning the organization of the car park is aimed at using intelligent transport systems in combination with the previous proposal of reverse parking. Compact parking with variable signal (tested in Germany) shows the exit times of the parking space and thus the driver chooses the parking space according to the planned departure on the signal [34,35]. This system allows multiple vehicles to be parked in a row without blocking each other because the vehicles leave the parking places gradually. The system is updated every 15 min to provide quality and accurate parking management. The compact parking system in combination with the reverse parking system makes it possible to park the vehicle for an undefined time. In case of a defect appearing on the vehicle, or the driver parks an unloaded vehicle and they do not know the exit time, they can park the vehicle in the first line, where they park by reversing or longitudinally along the edge of the car park at reserved places. Since it is not possible to return in this type of parking, a parking space occupancy detection system would need to be installed in the reverse parking line, and the driver is informed on the signal before entering the line whether is there a free parking place in the line and so how many free places there are. Based on this information, the driver can decide whether they choose the ITS (intelligent transportation system) way or the reverse parking way. An example of this parking management is as follows: Vehicle 1 knows when it plans to leave the car park, and therefore ranks straight on a branch with a compact parking system, where it also parks according to the selected time. Figure 6 shows that it is obvious that Vehicles 2 and 3 do not know when to leave the car park, so they will decide according to the signal at the entrance where they will park according to the number of available free places. chooses the parking space according to the planned departure on the signal [34,35]. This system allows multiple vehicles to be parked in a row without blocking each other because the vehicles leave the parking places gradually. The system is updated every 15 min to provide quality and accurate parking management. The compact parking system in combination with the reverse parking system makes it possible to park the vehicle for an undefined time. In case of a defect appearing on the vehicle, or the driver parks an unloaded vehicle and they do not know the exit time, they can park the vehicle in the first line, where they park by reversing or longitudinally along the edge of the car park at reserved places. Since it is not possible to return in this type of parking, a parking space occupancy detection system would need to be installed in the reverse parking line, and the driver is informed on the signal before entering the line whether is there a free parking place in the line and so how many free places there are. Based on this information, the driver can decide whether they choose the ITS (intelligent transportation system) way or the reverse parking way. An example of this parking management is as follows: Vehicle 1 knows when it plans to leave the car park, and therefore ranks straight on a branch with a compact parking system, where it also parks according to the selected time. Figure 6 shows that it is obvious that Vehicles 2 and 3 do not know when to leave the car park, so they will decide according to the signal at the entrance where they will park according to the number of available free places. This car park design, in combination with the compact parking and reversing parking system, increases the capacity of the car park within the same built-up area. The proposed car park with the possibility of return increases the comfort of parking and the availability of the petrol station. For a given sample area (the illustration does not feature all 118 parking spaces for simplicity), the car park has a capacity of 118 truck parking places. A car park using ITS has a capacity of 147 truck parking places in a smaller area on the same car park length, but with narrowed width (for unused places).

Discussion
The issue of truck parking is relevant worldwide, not just in the EU. Vehicles park in unauthorized places due to the full capacity of the legal car parks and also because the driver is This car park design, in combination with the compact parking and reversing parking system, increases the capacity of the car park within the same built-up area. The proposed car park with the possibility of return increases the comfort of parking and the availability of the petrol station. For a given sample area (the illustration does not feature all 118 parking spaces for simplicity), the car park has a capacity of 118 truck parking places. A car park using ITS has a capacity of 147 truck parking places in a smaller area on the same car park length, but with narrowed width (for unused places).

Discussion
The issue of truck parking is relevant worldwide, not just in the EU. Vehicles park in unauthorized places due to the full capacity of the legal car parks and also because the driver is subject to a fine in case the prescribed rest is not drawn. This situation is not sustainable in the long term, especially because of the expected growth of road freight transport output. Based on our research, we found that drivers, because of the fear of not finding a suitable parking place, park vehicles earlier before the set rules, earlier than they need to recover. Alternatively, they park vehicles during the day and drive at night when they cannot find a parking place. Such a situation decreases the safety of road transport. Our research also highlights insufficient equipment for existing car parks.
Some theoretical and practical implications are obvious in the study. If the equation is used for calculating parking spaces for trucks, the characteristics such as the intensity of traffic, length of driver's rest, average driving time, length of the solved section, and the average speed of trucks are not considered. In this paper, two practical proposals for freight transport parking areas were discussed. If the parking area with ITS is used, it will be space-efficient and thus lower costs. It is necessary to build new parking areas with accommodation. We have proven that on three selected routes there are only 1.10 to 1.43 parking places with accommodation for drivers per 100 km.
This study had a few limitations. The results of the questionnaire may not be accurate, and the sample size was 825 drivers. The equation for calculating parking spaces uses theoretical data. Sometimes, other facts affect the demand for parking spaces, and these are not included in the equation. Another limitation is that the proposed solution using ITS depends on a reliable and efficient information system.
Based on our research, the research hypothesis that there is insufficient parking capacity for trucks was confirmed. We highlight the method of calculating the necessary car park capacity for a specified traffic intensity on the road. By applying this method to the superior road network in Slovakia, we found that there is not a sufficient number of car parks for freight transport in any section.
We are aware that the establishment of new car parks is economically demanding, and as such, we offered two possibilities that increase the capacity of freight transport car parks without further demands on the car park area. The costs associated with each proposal are different. In general, the biggest are costs necessary for the construction of parking infrastructure, which are location, roads, asphalt surface, road equipment, etc. For parking areas with ITS, it is possible to save parking space. It is also important to take into account the cost of the information system itself.

Conclusions
During our extensive survey, we have found many important information form truck drivers. The survey showed that 92% of drivers adjust the driving time and their own working time to the situation in car parks. With our research, we have proved that the analyzed car parks do not achieve the demanded capacity. Additionally, the results of the survey confirm that it is possible to increase the capacity of existing car places by effective management. Our first proposal of parking area allows the return of the vehicle. Our second proposal is using the ITS, which increases the capacity of the car park within the same built-up area. We have also created a methodology that can determine the necessary number of parking spaces that comply with the requirements of social law.