MX2014009409A - Method for producing a fibre concrete slab for paving low-traffic roads, concrete slab, and method for paving low-traffic roads. - Google Patents

Abstract

The invention relates to a method for paving low-traffic roads or paths with a paving slab that is cast in situ and has a width Dx narrower than the smaller value of D1 and D2. D1 is the free distance between the front wheels of a standard haulage truck and D2 is the distance separating the wheels of the rear-wheel train. The length of the paving slab Lx is shorter than the value of the length L of the free distance between the front axle and the first rear axle of the wheel train of the standard haulage truck, such that the dimensions Dx and Lx mean that a single wheel or, alternatively, a single wheel train of the standard truck is always supported by the paving slab, touching same. The method comprises the steps of: providing for paving either a low-traffic road which has neither asphalt or concrete paving, or a low-traffic path; evening out and levelling the road or path to be paved; determining the width and length of the paving slab and establishing the thickness thereof in accordance with the amount of traffic and the traffic load, the bearing capacity of the natural ground, the strength of the concrete, the residual strength thereof and the climate, such that the thickness is between 5 and 15 cm; determining the amount of fibre required for a required design residual strength of between 10% and 50% of the maximum strength of the concrete; and preparing the mixture of concrete and fibres which are selected from steel, glass, polypropylene, carbon or another structural fibre for concrete. In addition, the method comprises pouring the mixture of fibre concrete directly onto the road or path to be paved according to the size of a dimensioned paving section, or pouring the mixture of fibre concrete directly onto the road or path to be paved. The invention also relates to a concrete slab for paving low-traffic roads or paths and to a method for producing same.

Description

METHOD OF MANUFACTURING A CONCRETE SLAB WITH FIBER FOR THE PAVING OF LOW TRAFFIC ROADS, CONCRETE SLAB AND METHOD FOR PAVING LOW TRAFFIC ROADS Field of the Invention The invention relates to a concrete slab with fiber for the paving of low traffic roads or the like, which has a smaller thickness and dimensions of pre-established width and length.

The present invention also relates to the method of manufacturing the slab with fiber to perform the paving of low traffic roads and the method of paving low traffic roads.

Background of the Invention The dirt roads are highly polluting, since the circulation of vehicles in them, generates large amounts of dust, for this reason it is recommended that they be paved with gravel in order to make them more passable, since it is possible to eliminate the lifting of dust. However, in gravel roads vehicles have less stability and grip, and to travel on gravel roads it is recommended that vehicles move at moderate speed and have their tires well inflated, so that the stones do not break the tread .

In addition to this, the cost of maintenance of these roads is very high, especially in those that circulate trucks, since the surface of Rolling based on granular materials tends to decompact with vehicle passes eliminating good quality material from the surface producing calamine and holes in the surface The problems detected in the gravel roads generate the need to pave the road with another material or to perform some treatment to the gravel surface to improve the passability of the vehicles. Generally, the solution in these cases is the asphalting of the road. On the other hand, there is also the possibility of paving the road with concrete, but this solution, although more durable, can be more expensive than the asphalting process. In addition to the above, in both cases it is necessary to remove part of the existing road and replace it with a good quality granular folder, to obtain both the structural capacity and the existing soil erosion; this not only increases the cost of the solutions but also is not very sustainable since it is necessary to eliminate material out of the way.

Additionally, when choosing the most suitable material for paving, it is necessary to bear in mind, in the case of concrete, the dimensions of the slabs to be used in the paving of roads. In general, concrete slabs for road pavements have dimensions that are usually one-way wide, usually 3,500 mm, having a length of 3,000 to 6,000 mm. To support the load of heavy trucks that generate the greatest stresses and stresses to which the slabs are subjected, it is necessary to worry about the thickness of the slabs, since the thickness is relevant to avoid cracks in the slabs. Furthermore, some of the designs of slabs of the state of the art have an armor, mesh or reinforcement in their structure, in order to ensure the durability of the slab, but said aggregate results in a considerable increase in the cost of the design. of the slab. In the state of the art, in addition, the concretes with fibers are developed, which consist of concrete made with cement that contains fine and coarse aggregates and discontinuous fibers, where the fibers can be natural or artificial and fulfill the function of reinforcing the mass cement, increasing the resistance to fatigue and in this way retard the growth of cracks, thus increasing the ductility by transmitting the stress through the cracked section. In addition, the reinforcing fibers improve the impact resistance, and allow to distance the contraction joints by hydraulic retraction. The fibers most commonly used for this type of concrete are steel, glass, polypropylene, carbon and aramid fibers, and in general they are called structural fibers.

In concrete with fiber, once the first crack of the concrete matrix has been produced, the tensile stress must be distributed in the fibers present in the cracking zone, these must hold together the edges of the crack with the smallest possible width. As the tensile stress continues to increase, the concrete begins to deform, which is why the residual behavior of the fibers is very relevant.

This effect in conjunction with the support provided by the floor, generates a cracking pattern different from concrete without fiber, spreading stress and decreasing fatigue at the tip of the cracks considerably increasing the capacity of load cycles and therefore the duration.

For the determination of residual strength The residual strength, although not a real property, but an engineering effort, calculated on the basis of the properties of the section, according to the theory of simple bending engineering for linear and non-linear elastic materials (without cracks), in practical terms is the ability of the material to continue taking loads once Asurado.

The incorporation of fibers increases the resistance to bending of a slab, a fact that is demonstrated in the tests of plates resting on the ground, but it is not clearly reflected when performing beam tests in the air.

The current designs of pavements are directly linked to the resistance to bending of the concrete (MOR) and do not take into account the residual resistance given by the fibers. Therefore, beam tests do not reflect the real contribution of fibers in concrete in the design of pavements. As a consequence, for beam tests, the design would provide the same thickness of pavement for a concrete with fibers as for one without fibers.

Through the test a series of load-deformation points is obtained as shown in the illustration (ASTM 1609) (Figure 4).

In figure 4 P1 represents the strength of the concrete, that is to say the maximum load that resists this (MOR); P150.0.75 corresponds to the residual resistance, that is to say the load that the concrete resists to the deformation of S / 600, where S is the separation between the supports (mm); and P150.3.0 corresponds to the residual strength, that is to say the load that the concrete resists to the deformation of S / 150.

With the data described above, the maximum voltage for any value of P can be calculated with the following equation: Where: F = Voltage (MPa) P = Load (N) L = Support spacing (mm) b = Average width of the test piece in the fracture (mm) d = average height of specimen in the fracture (mm) Following the procedure of the ASTM 1609 standard, if the fracture occurs in the central third, the equivalent ratio of flexion R3, e is obtained as follows: 1. fifty ¾.ß = * 100 * ß MOR Therefore, some proposed designs have modified the input variable of flexural strength (MOR) in the current design of pavements. The aim is to include the residual strength that fibers deliver when performing beam tests on concrete pavements.

Other studies have shown (Altoubat et al., 2004) that the increase in the resistance to bending of slabs due to the use of fibers is directly related to the residual resistance R3, e.

With this the proposed method for the design of pavements to incorporate the effect of the incorporation of fibers is given by the following calibration factor: + - 100) ' Where: C2 * = Calibration factor of the resistance in the fatigue equation R3, e = Equivalent ratio of residual resistance to 3 mm of arrow in beam test in air.

According to the previous equation, a concrete with fiber that reaches a residual resistance ratio of 20% will increase by 20% the resistance to bending in a pavement. With this increase, the thickness of the slab can be reduced or it will have a longer useful life for the same thickness.

Based on the maximum tensile stress, in each load position, the steps allowed for each condition (Nijk) are calculated based on the fatigue equation: (Covarrubias 2008) Where the variables are defined as: Nijkl = Permitted passages for axis in position k, bank i (temperature), load level j, and critical tension in the upper and lower part. oijkl = Main stresses calculated with ISLAB2000 for axes in position k, warpage i and load j, and critical stress in the upper and lower part.

MOR = Resistance to concrete bending at 90 days.

C1 = Correction factor for geometry of the slab and its thickness.

C2 = Fiber structural correction factor.

C3 = Load correction factor at the edge.

Using the Miner hypothesis, the fatigue damage for each position is determined at the top and bottom of the slab based on the following formula: Where: FD = Fatigue damage for a given position of the k-axis. nijk = Number of passes for local voltage I for condition i, j, k.

Nijk = Number of passes allowed for local voltage I for condition i, j, k.

In JP2004224633 a pre-stressed concrete slab is described, which is easily manufactured and reduces losses by pretension. The prestressed concrete slab consists of a cured body, whose composition includes 100 parts of cement mass, 10-40 parts of fine mass particles, 15-55 parts of inorganic mass particles, water reducing agent, and water. The composition may further contain fine aggregates of particles less than or equal to 2 mm in diameter and one or more types of fibers selected from the group consisting of metal fibers, organic fibers and carbon fibers.

In CN 101823860, concrete slabs with powder fibers are described, which comprise the following components in proportions in weight: 35-40% of quartz powder, 30-35% of cement, 6% of fibers and 24-29% of reaction assistants, where the fibers are vegetable fibers and / or glass fibers resistant to alkalis and the reaction comprises 23-28% mineral assistant and 1% chemical assistant. With the mixture, a concrete slab with active, high-strength powder fibers is obtained, which has the advantage of being lighter.

For its part, document CN 101294430 describes an aerated concrete slab in an autoclave containing carbon fibers.

WO0212630 describes a system and method for building large and continuous concrete slabs without the use of conventional control joints for shrinkage. The base of the system is formed by a network of crack inducers, on which the concrete is poured in such a way that the network is covered by concrete. The inductors will allow the formation of cracks in the slab, once the concrete slab is being used.

The national registry CL 44.820 describes a method of construction of a concrete slab and the formed concrete slab comprising the construction of a concrete slab whose maximum length is 3 meters and its maximum width is equivalent to half the width of the track. The concrete slab formed has a size such that always a single wheel, or else, a single set of wheels of the wheel train of a vehicle, will be touching and resting on the slab.

Among the documents of the state of the art there are documents that describe concrete slabs with different types of fibers, but these slabs are not intended to be used in pavements of low traffic roads.

Therefore, it would be desirable to have a concrete slab to be used in low traffic roads on existing floors, which is easy to manufacture, with lower installation and manufacturing costs, and greater durability.

Therefore, an objective of the present invention is to have a concrete slab with structural fiber, to be installed on low traffic roads.

Another objective is to have a method of manufacturing a concrete slab in situ on low traffic roads and a method of paving low traffic roads, with a mixture of concrete, which in this case carries structural fiber.

The present invention then corresponds to a method of paving low traffic roads with a concrete slab optimized with fiber, to the concrete slab with obtained fiber, and to the method of obtaining the concrete slab with fiber.

Brief Description of the Drawings The invention will be described below with reference to the drawings, which are included to provide a better understanding of the invention.

Figure 1 is a diagram of a heavy load truck showing the relevant measure D1, to be considered in the present invention.

Figure 2 is a diagram of a heavy-duty truck showing the relevant measure D2, to be considered in the present invention.

Figure 3 is a schematic of a heavy-duty truck showing the relevant measure L, to be considered in the present invention.

Figure 4 is a schematic in top view of the maximum size that a concrete slab of the present invention should have.

Figure 5 is another schematic in top view of the maximum size that a concrete slab of the present invention should have, in relation to a standard or average cargo truck, with a train of wheels.

Figure 6 corresponds to a graph showing the strength of the concrete through the deformation of the slab as a function of the load.

Figure 7 corresponds to a graph showing an example of the expected traffic for different thicknesses.

Detailed description of the invention The present invention corresponds to a method of manufacturing a concrete slab with fiber for the paving of low traffic roads, where a low traffic road comprises a circulation of no more than 50 trucks per day.

This invention considerably reduces the cost of low traffic roads by making it competitive with the most economical existing solutions, even with asphalt pavements of low traffic. In addition, with regard to the latter, the duration will be longer, because the concrete does not have significant deterioration due to environmental agents and fiber. In the case of cracking, it will lengthen the life of the latter even more, making it not only an economic pavement in its initial cost but also in the design period.

Below is a comparative table of initial costs of the possible structures in concrete Transit (EE) tf Trad TCP UTCP 50000 $ 170540 $ 158,750 $ 150,920 100. 000 $ 179,067 $ 169,700 $ 162,260 150. $ 187,594 $ 180,650 $ 173,600 250. 000 $ 204,648 $ 191,600 $ 184,940 Where "H ° Trad" refers to concrete designed by traditional methods, "TCP" refers to the concrete protected in CL 44,820, and "UTCP" represents the concrete with fiber of the present invention.

In addition, the present invention relates to the concrete slab with fiber having a preset width and length, depending on the mechanical stresses generated by a standard or average cargo truck having a clear distance between the front wheels and a width of track of a train of rear wheels, and a long free distance between the front axle and the first rear axle of said train of wheels, and approximately 5 to 15 cm thick. The present invention will use as a reference means the support points of a load or pattern truck, generated by the four points of support of its wheels, bearing in mind that a load truck is usually provided with two front wheels and two pairs of wheels rear (train of rear wheels). For the purposes of describing the width and length dimensions of the concrete slab with fiber, the variables D1, D2 and L (Figure 1) are defined in a standard or average load truck. In this way, the front wheels of a load or pattern truck will be separated by a free distance D1 and the wheels in the rear wheel train will be separated by a free distance D2. In turn, the free distance between the front axle and the first rear axle will be L.

The concrete slab comprises a dose of between 1 kg / m3 (kilogram of fiber per cubic meter of concrete) and 6 kg / m3 for plastic fibers and between 15 kg / m3 (kilogram of fiber per cubic meter of concrete) and 40 kg / m3 of structural metal fiber. These doses, of these fibers or others that are used must be such that they must generate a residual resistance of between 10% and 50% of the maximum strength of the concrete. The possible fibers to be added to the mixture are steel, glass, polypropylene or carbon fibers or some other type of fiber structural for concrete, and these fibers can be added independently or based on mixtures of them. The thickness of the slab is approximately 5 to 15 cm. The minimum dimensions of the width and length of the slab must be greater than 50 cm and the maximum dimensions of the width and length of the slab must be less than 2.5 meters. The width and length dimensions of the slab allow that always a single wheel, or else, a single wheel train of said standard or average truck, is touching and resting on the slab.

In order to achieve that always a single wheel or a single wheel train of the standard or average truck is touching and resting on the slab, the slab must have a maximum width (Dx) that is less than the lowest value of free distance between D1 and D2, and a maximum length (Lx) that is less than the free distance L. In this way, the concrete slab with fiber will have a maximum width Dx and a maximum length Lx, which ensures that only one of the wheels or a single train of wheels, leans on the slab when the truck transits on the road or highway.

However, in practical terms, the paving pads can be made larger than the dimensions Dx and Lx, and once manufactured these can be cut to dimensions Dx and Lx, allowing the natural cracking by shrinkage of the concrete plus the loads of traffic, produce these dimensions by cracking the slab, or induce this cracking in mechanical devices. This, in such a way to make the cuts or cracking of paving slabs at distances that allow the generation of slab dimensions that change the load effect of the axles of the trucks or vehicles used as design reference. In a preferred embodiment of the present invention, the cuts are made less than 2.5 meters in the longitudinal direction and a longitudinal cut that decreases the width of the slab to at least one dimension equivalent to half the width of the track. In the Chilean case, the slabs would ideally be 1.75 meters long by 1.75 meters wide. These dimensions are not the only ones possible, but it generates an example that makes the system more understandable. Currently this cut is usually made at distances between 3 and 6 meters in the transverse direction, leaving slabs of these lengths in the longitudinal direction, and its width of the normal width of the track of 3.5 meters.

The concrete slab will be placed directly on the natural terrain and except in the case of not being suitable or not being homogeneous, a replacement should be generated, as a punctual improvement of the subgrade, However, this improvement does not involve adding any type of additional surface. As an example of this improvement, an excerpt from the manual of Roads of Chile is shown.

"It is necessary to remove inappropriate material from the soil when it does not have the minimum support capacities stipulated in 5.201.3 of MC-V5 In summary, those materials that meet at least one of the following conditions will be considered inadequate materials: 1. Materials with a support power lower than 3% CBR, measured according to the Method stipulated in 8.102.11 of the MC-V8, unless it can be compacted on site and achieve a support equal to or greater than 3% CBR. 2. Materials containing more than 3% by weight of dry organic material baked at 60 ° C, this will be determined according to the test described in Road Manual V.5 chapter 5.201.303. 3. Material whose percentage of expansion is greater than 3%, according to the test 8,102.11 of MC-V8. " The minimum value of the width Dx is greater than 50 cm, and alternatively, the maximum dimension of the width is equivalent to half a normal track. In the same way, the minimum value of the Lx length is greater than 50 cm and the maximum length can correspond to 3.0 meters, depending on the wheelbase of the reference truck.

The method of manufacturing the concrete slab with fiber comprises: a) determine the width of the slab (Dx) at a free distance Dx, which is less than the smallest value between D1 and D2; b) determining the length of the slab at a free distance Lx, less than the value of the length L of free distance between the front axle and the first rear axle of said wheel train of the standard or average cargo truck; c) establish the thickness of the slab, according to: the amount of traffic, the traffic loads, the support capacity of the natural terrain, the strength of the concrete, the residual strength of the concrete and the climate; such that the thickness is within the range of 5 to 15 cm; d) determine the fiber dose so that the required residual design strength is from 10% to 50% of the maximum strength of the concrete and prepare the concrete mix by adding the fiber with doses between 1 kg / m3 and 6 kg / m3 for plastic fibers, and between 15 kg / m3 and 40 kg / m3 of metallic fiber, where the fiber is selected from steel, glass, polypropylene or carbon fibers; Y e) pour the concrete mix with fiber directly on the path or path to be paved.

For its part, the method of paving low traffic roads includes: a) have a road to pave that does not have a binder of asphalt or concrete or a path to pave; b) level and homogenize the road or path for paving; c) determine the width of the slab (Dx) at a free distance Dx, which is less than the smallest value between D1 and D2; d) determining the length of the slab at a free distance Lx, less than the value of the length L of free distance between the front axle and the first rear axle of said wheel train of the standard or average cargo truck; e) establish the thickness of the slab, according to: the amount of traffic, the traffic loads, the support capacity of the natural terrain, the strength of the concrete, the residual strength of the concrete, and the climate; such that the thickness is within the range of 5 to 15 cm; f) determine the fiber dose so that the required residual design strength is from 10% to 50% of the maximum strength of concrete and prepare the concrete mix by adding the fiber with doses between 1 kg / m3 and 6 kg / m3 for plastic fibers and between 15 kg / m3 and 40 kg / m3 of metallic fiber, where the fiber is selected from steel, glass, polypropylene or carbon fibers; Y g) pour the concrete mix with fiber directly on the road or path to be paved from stage a), in a size of a paving cloth greater than the measurements determined in c) and d), and size the paved cloth to the measurements determined in steps c) and d); or h) pouring the concrete mixture with fiber directly on the path or path to be paved from stage a), on a paving cloth having the measurements determined in steps c) and d).

The slab of the present invention is only for paving roads that do not have a binder of asphalt or concrete, or paths and does not contemplate the rehabilitation of old pavements with superimposed layers adhered to concrete. In addition, the slabs of the present invention can be placed on any type of artificially stabilized land.

The leveling and homogenization of the road to be paved includes the removal of material that is not suitable for the road.

Additionally, the slabs of the present invention can be manufactured in sizes larger than the Dx and Lx measurements., and they can not be cut to the size established by the measures Dx and Lx, in such a way that the road is paved with the slabs of larger sizes than the measures Dx and Lx. In this case when the vehicles move along the road, due to the weight of the vehicles, the cuts will be generated, leaving in this way slabs whose size will be such that only one wheel, or else, a single wheel train of said truck pattern or average, is touching and is resting on the slab.

The slabs of the present invention have the special feature of not requiring any type of reinforcement, meshes, load transfer bars, tie bars, side pins or structural base in their construction.

The slabs of the present invention, having structural fiber, have increased resistance to fatigue, increased load transfer, and mooring of the slabs to prevent their separation or to control soil erosion.

Figure 5 corresponds to an example of the present invention and shows a graph illustrating the minimum expected traffic of the paving slabs of the present invention at different thicknesses of slabs. Each curve of the graph represents the values obtained at the different thicknesses of the slabs. The curves, identified from the lower curve to the upper one, correspond to 9cm, 10cm, 11cm, 12cm and 13cm of slab thickness, respectively. The graph represents the characteristic resistance to flexotraction at 28 days, with 20% fiber, with the value of HF 4.5 at 28 days.

The X-axis of the graph shows the value of CBR (California Bearing Ratio) or relative support value of the soils, which establishes a measure of resistance to cutting directly.

As an example, we have the following type profiles: Subgrade CBR > 10% Notes: 50% of slabs with a crack are considered as fault criteria, due to the presence of fiber and the low traffic for which this solution was designed, the actual expected traffic is greater than that shown in the graph.

The average thickness of the section is considered, so in the case of making a trapezoidal profile it is recommended to reduce the center of the track by 1 cm and increase the edge by 2 cm. This will decrease the edge effect so the pavement will last longer than the graph shows.

This table is only a reference, the pavement should be designed with OptiPave or with a specific Abaco design.

Claims (10)

1. Method of paving roads or trails of low traffic with a paving slab that is poured in situ, where the paving slab has a slab width Dx that is less than the lowest value between D1 and D2, being D1 the free distance that separates the front wheels of a cargo or pattern truck and D2 the free distance D2 that separates the wheels in the rear wheel train; and a length of slab Lx that is less than the value of the length L of the free distance between the front axle and the first rear axle of said wheel train of the standard or average cargo truck, such that the dimensions Dx and Lx allow that always a single wheel, or else, a single wheel train of said standard or average truck is touching and resting on the slab CHARACTERIZED because it comprises: a) have a road to pave that does not have a binder of asphalt or concrete, or a paving path, both of low traffic; b) level and homogenize the road or path for paving; c) determine the width of the slab (Dx); d) determine the length of the slab at a free distance Lx; e) establish the thickness of the slab, according to: the amount of traffic, the traffic loads, the support capacity of the natural terrain, the strength of the concrete, the residual resistance of the concrete and the climate; such that the thickness is within the range of 5 to 15 cm; f) determine the fiber dose so that the required residual design strength is from 10% to 50% of the maximum strength of the concrete and prepare the concrete mixture by adding the fiber, with the fibers selected from steel, glass, polypropylene or carbon or some other type of structural fiber for concrete; and if the fibers are plastic fibers the mixture contains from 1 kg / m3 to 6 kg / m3 (kilograms of fiber per cubic meter of concrete), and if the fibers are metallic fibers the mixture contains between 15 kg / m3 to 40 kg / m3; Y g) pour the concrete mix with fiber directly on the road or path to be paved from stage a), in a size of a paving cloth greater than the measurements determined in c) and d), and size the paved cloth to the measurements determined in steps c) and d); or h) pouring the concrete mixture with fiber directly on the path or path to be paved from stage a), on a paving cloth having the measurements determined in steps c) and d).

2. Method of paving roads or trails of low traffic, with a paving slab, according to claim 1, CHARACTERIZED because a low traffic road comprises a circulation of no more than 50 trucks per day.

3. Method of paving roads or trails of low traffic with a paving slab, according to any of claims 1 to 2, CHARACTERIZED because the minimum value of Dx is greater than 50cm and the maximum dimension of Dx is half the width track.

4. Method of paving roads or trails of low traffic, with a paving slab, according to any of claims 1 to 3, CHARACTERIZED because the minimum value of Lx is greater than 50 cm and the maximum dimension of Lx corresponds to 3.0 meters.

5. Concrete slab for the paving of roads or trails of low traffic, which has a slab width Dx that is less than the lowest value between D1 and D2, being D1 the free distance that separates the front wheels of a cargo truck or skipper and D2 the free distance D2 that separates the wheels in the rear wheel train; and a length of slab Lx that is less than the value of the length L of the free distance between the front axle and the first rear axle of said wheel train of the standard or average cargo truck, such that the dimensions Dx and Lx allow that always a single wheel, or else, a single wheel train of said standard or average truck is touching and resting on the slab; CHARACTERIZED because it comprises a mixture of concrete and fiber, the fibers being selected from steel, glass, polypropylene or carbon fibers or some other type of structural fiber for concrete; because if the fibers are plastic fibers the mixture contains from 1 kg / m3 to 6 kg / m3 (kilograms of fiber per cubic meter of concrete), and if the fibers are metallic fibers the mixture contains between 15 kg / m3 to 40 kg / m3; and because the thickness of the slab is within the range of 5 to 15 cm and the amount of fiber to be added to the mixture must be such that the slab has a residual strength from 10% to 50% of the maximum strength of the concrete.

6. Concrete slab for paving roads or trails of low traffic, according to claim 5, CHARACTERIZED because the value minimum of Dx is greater than 50cm and the maximum dimension of Dx is half the width of the track.

7. Concrete slab for paving roads or trails of low traffic, according to any of claims 5 to 6, CHARACTERIZED because the minimum value of Lx is greater than 50 cm and the maximum dimension of Lx corresponds to 3.0 meters.

8. Concrete slab for paving roads or trails of low traffic, according to any of claims 5 to 7, CHARACTERIZED because said concrete slab is suitable for low traffic roads that include a circulation of no more than 50 trucks per day.

9. Method of manufacturing the concrete slab of claim 5 comprising making a paving slab that is poured in situ, where the paving slab has a slab width Dx that is smaller than the smaller value between D1 and D2, with D1 being free distance separating the front wheels of a cargo truck or pattern and D2 the free distance D2 that separates the wheels in the rear wheel train; and a length of slab Lx that is less than the value of the length L of the free distance between the front axle and the first rear axle of said train of wheels of the standard or average cargo truck, such that the dimensions Dx and Lx allow that always a single wheel, or else, a single wheel train of said standard or average truck is touching and resting on the slab CHARACTERIZED because it comprises: a) determine the width of the slab (Dx) at a free distance Dx ,; b) determine the length of the slab at a free distance Lx; c) establish the thickness of the slab, according to: the amount of traffic, the traffic loads, the support capacity of the natural terrain, the strength of the concrete, the residual strength of the concrete and the climate; such that the thickness is within the range of 5 to 15 cm; d) determine the fiber dose so that the required residual design strength is from 10% to 50% of the maximum strength of concrete and prepare the concrete mixture by adding the fiber, with the selected fibers being steel fibers, glass fibers, polypropylene or carbon or some other type of structural fiber for concrete; and if the fibers are plastic fibers the mixture contains from 1 kg / m3 to 6 kg / m3 (kilograms of fiber per cubic meter of concrete), and if the fibers are metallic fibers the mixture contains between 15 kg / m3 to 40 kg / m3; Y e) pour the concrete mix with fiber directly on the road or paved footpath, of low traffic.

10. Method of manufacturing a concrete slab according to claim 9, CHARACTERIZED because a low traffic road comprises a circulation of no more than 50 trucks per day.