FR2568905A2 - Method for developing a sportsfield or a playing field - Google Patents

Abstract

Method for creating a usable field covered with a surface of vegetation such as a sportsfield. Longitudinal trenches or channels 1, 2' are formed by means of an earthworks machine, the progress of the ploughshare of the machine producing, by a subsoiling effect, the lifting without overturning of the earth and at the same time, the formation of the trench which is subsequently filled with mineral particles and aggregates, and the method is characterised in that the aeration of the site is completed by forming, during a subsequent stage, evenly distributed bore holes 10, 10', 10" of approximately vertical orientation. This is carried out at least in the areas of the site separating the parallel discharge channels or trenches, these bore holes being filled with sand; the invention also relates to the site thus created. Application to the creation of a sportsfield or leisure site.

Description

The present invention relates to improvements and improvements to the process for producing and fitting out sports and playgrounds as described in the main patent.

According to the main patent, provision has been made to produce, with a view to the formation of a field for the practice of sports and practicable in all seasons, a series of parallel slots or trenches filled with aggregates of suitable particle size in order to ensure the drainage of infiltration and surface water to the drainage devices; and more particularly according to the main patent, the formation of trenches filled with mineral particles is accompanied and is carried out in the form of a subsoiling operation by means of a machine whose ploughshare opens the trench by attacking the ground from the down and lifting it up.

Under these conditions, a dislocation of the structure of the surface soil is obtained with the formation of a multiplicity of slits running in multiple directions and in particular in the horizontal direction, slits which start from the longitudinal trench, thereby ensuring branching and a network of side branches to feed the trenches filled with aggregates.

It has appeared to the applicant that the work of aerating the soil in the zones separating two parallel longitudinal trenches or slots and filled with aggregates could be usefully supplemented, in particular in the case of particularly compacted soils.

In fact, the soil aeration work is carried out suitably at the level of the passage of the machine allowing the formation of longitudinal slots and in the lateral zones with respect to this longitudinal slot or trench, the soil is usefully worked to obtain the effect of profusion and aeration by subsoiling.

However, this destruction of the compacted structure of the soil takes place essentially in the lateral zones with respect to the trenches; so that if one wants to obtain a sufficiently regular and efficient work of aeration and unpacking of the entire surface of the ground it then becomes necessary to bring the trenches considerably closer together; which would result in major work and an increase in costs.

It therefore remains desirable that the drainage trenches remain separated by an interval that they can serve by absorption and evacuation of infiltration water and runoff water.

But when the trenches are separated by too large a gap, the central area between the trenches is then lightly worked and keeps a relatively compact and poorly ventilated structure.

In addition, the subsequent and subsequent work on the passage of the subsoiling machine frequently leads, by the need to circulate machines on the ground, to a compaction of the soil which partially cancels the effects of the previous subsoiling.

The present invention overcomes these drawbacks and makes it possible to obtain the advantages of the method described in the main patent by virtue of the formation of a structure and of a water drainage network; at the same time the improvement provided for in this addition certificate also makes it possible to obtain a regularly ventilated structure over the whole of the ground which will allow good drainage of water and a hygrometric balance between the surface soil carrying the plant mat and the sub - ground thanks to a regular network of circulation and exchange.

To this end, the invention relates to a process for producing a practicable surface coated with a plant surface such as a sports field and of the type in which longitudinal trenches or slots are formed by means of a working machine. of the soil, the advancement of the ploughshare of the machine producing by subsoiling effect the uplifting without overturning of the earth mass at the same time as the formation of the trench subsequently filled with particles and mineral aggregates, and the process is characterized in that the aeration of the ground is completed by the formation, in a later phase, of wells, regularly distributed and of substantially vertical orientation, this at least in the zones of the ground separating the slots or parallel evacuation trenches.

Preferably, the wells are cylindrical in shape and have a cross section of diameter between 1 and 10 cms and preferably of the order of 1.5 to 3 cms.

More particularly according to an advantageous embodiment of the invention, the vertical or substantially vertical wells, after formation, are filled with sand.

According to one aspect of the invention, the wells are produced by passing a machine provided with teeth, the teeth being assembled and mounted on a mobile support animated with a cyclic movement allowing the penetration of the teeth into the ground in a substantially linear movement. along the axis of the teeth and, their lifting in an angular tilting movement capable of lifting the portion of the ground located behind the teeth relative to the direction of advance of the machine.

According to a development of the method according to the invention, prior to the formation of the wells by passage of the machine provided with the penetration and tilting teeth, sand is poured which is spread over the ground, the sand being displaced, after passage of the perforation machine, by moving a flexible support such as a clean net to cause the filling of the wells with sand and thus fixing the well in its structure thanks to the presence of filling sand.

The invention also relates to a sports field obtained by implementing the above method and characterized in that it comprises parallel longitudinal trenches filled with mipereral aggregates and flush with the upper ground level, the strips of land located between two trenches being perforated and comprising micro-wells, spaced apart in a substantially regular manner and filled with sand, the depth of the wells is substantially equal to two thirds of the depth of the evacuation trenches.

The invention also relates, according to a more particular development, to a sports field as specified above and the surface layer of which is lightened and aerated by the formation of a network of horizontal capillary slots by virtue of prior subsoiling work, this network of horizontal capillary slits joining the micro-wells together and joining the micro-wells to the evacuation and drainage slits, the ground comprising a surface protective layer of pure sand.

Preferably the depth of the wells is between 10 and 30 cms and preferably between 12 and 20 cms.

Other characteristics and advantages of the invention will emerge from the description which follows and which is given in connection with a preferred embodiment and illustrated in the appended drawings.

Figures 1,2 and 3 give schematic views of one of the phases of making micro-wells in the field.

Figure 4 gives a sectional view of the terrain once completed.

It can be seen that the land was first worked in accordance with the main patent in order to obtain the formation of the 1.1 'trenches or drainage slots obtained by subsoiling.

In other words, these trenches were produced by lifting the ground by passing the machine according to the main patent, which makes it possible to obtain a network of substantially horizontal capillary slots 2,2 ′, 3,3 ′, 4 , 4 'which branch out from the 1,1' drainage slots.

It can be seen in the drawing that the effect of this capillary network is relatively limited at the level of the areas adjacent to the slots 1,1 ′. So that the central zone located between the slots 1 and 1 ′ only undergoes very partially the subsoiling action.

The process in accordance with this addition certificate then makes it possible to advantageously complete the working of the soil so as to obtain a homogeneous structure and usefully distributed over the whole of the ground by creating a particularly dense evacuation network and cooperating with the main network consisting by the drainage slots 1 and 1 '.

To this end, we begin by spreading on the ground the layer of sand 5 according to a thickness of the order of 1 to 4 cms to achieve a final thickness after treatment of the order of 1.5 cm to 2 cms.

After which, a machine is made to circulate on the ground, of the type known per se, and comprising sets of teeth mounted on supports animated in a cyclic movement.

The action of the teeth is illustrated schematically in Figures 1,2 and 3.

We see that in a first movement, the tooth 6 is engaged in the ground in a substantially linear movement corresponding to the axis of the tooth, this from its support 7, and until the tooth penetrates fairly deeply into the ground to a depth of the order of 1 to 2 meters.

And in FIG. 3 we see the tooth previously driven into the ground and still in the driving-in position, follow a tilting movement by traction on the upper connecting rod 8 and at the same time the support 7 is raised by raising the tooth 6.

In this tilting movement we see that the part of the ground and the ground which is located behind with respect to the direction of advance of the machine represented by the arrow F (FIG. 1) is raised and a movement is thus obtained d ventilation by expansion, expansion and formation of a multitude of slots which open onto the well shown on the right-hand side of FIG. 3.

The passage of the machine is accompanied by the drag of a flexible structure, such as a net 9 which stirs regularly and over a fairly long length the upper layer of sand 5 and causes under these conditions the fall of sand in the individual micro-wells 10, 10 ', 10 "which are thus stabilized in their structure being filled with sand and any subsequent movement or pressure on the surface of the ground can no longer result in a recolematisation of the wells which are thus stabilized in their shapes and their dimensions.

We then obtain the structure as shown in Figure 4 in which we see that the interstitial part between the drainage slots and 1 'is filled by a very dense network of vertical wells or micro-wells of about 80 per meter square, these micro-wells being filled with sand and therefore stabilized; while these micro-wells branch into a multiplicity of capillary slits opening into this well and allowing gas exchange and the equilibrium of the hygrometric distribution favoring the vegetation of grasses sown later.

This network of capillary slits in fact allows communication between the wells and between them and the wells with the slits or drainage trenches 1,1 '.

There is thus obtained a permanent aeration of the soil in depth thanks to the presence of wells which penetrate to a depth of the order of 12 to 30 cms.

Precipitation can flow and be removed very easily.

In fact, this network of micro-wells advantageously completes the drainage action of the slots or trenches 1 and 1 '.

The wells are already in themselves capable of absorbing a large quantity of water which can then be distributed in the soil thanks to the horizontal micro-slots; so that a large quantity of water, during intense precipitation, can be immediately absorbed before reaching saturation.

But this absorption effect also allows significant water retention and the constitution of a reserve for dry periods.

This avoids the phenomenon of rejection of water by surface runoff during a significant precipitation, the deep ground remaining very dry and therefore not allowing to feed the roots for a period of time between several precipitations.

The rale of water tank and distributor also plays for the diffusion of the principles of soil enrichment in particular the agents of culture for example the fertilizers and the oxygen which can be distributed in solution; these principles in solution in water are absorbed by the soil in the zone 11 corresponding to the enriched topsoil located immediately below the surface layer 12 which constitutes the support of the vegetation.

These agents can therefore be stored and taken up by the roots in order to maintain the good condition and health of the plant surface.

The process of the invention thus allows better use of the fine sand which is generally used and which traditionally is incorporated into the upper surface of the topsoil.

The addition of sand to the upper layers results in the prior art in the formation of a surface layer which is superimposed without interaction on the lower layer without exchange given the too different physical characteristics between the light and airy upper layer thanks to the presence of sand and the immediately lower layer which remained compacted and waterproof; so that in case of excess water the latter stagnates or must be evacuated.

While in the context of the present invention it is the whole of the sub-layer which, thanks to the formation of the wells and to its aeration, plays its role of absorption and reservoir allowing a permanent inter-action between the upper layer 12 and the layer constituting the reserve infrastructure 11 in symbiosis and in permanent equilibrium with the upper layer.

This gives satisfactory conditions for the health of the plant cover.

Claims (9)

1 - Method for producing a practicable surface coated with a plant surface such as a sports field and of the type in which longitudinal trenches or slots (1.1 ′) are formed by means of a work machine soil, the advancement of the ploughshare of the machine producing, by the effect of the subsoil, the lifting without overturning the mass of earth at the same time as the formation of the trench subsequently filled with particles and mineral aggregates, characterized in that the aeration of the ground is completed by the formation, in a later phase, of wells (10, 10 ', 10 ") regularly distributed and of substantially vertical orientation, this at least in the areas of the ground separating the parallel evacuation slots or trenches. 2 - Method according to claim 1, characterized in that the wells (10,10 ', 10 ") are of cylindrical shape and have a section of diameter between 1 and 10 centimeters and preferably of the order of 1 , 5 to 3 cms. 3 - Method according to one of claims 1 or 2, characterized in that the vertical wells (10,10 ', 10 ") substantially vertical, after formation, are filled with sand. 4 - Method according to one of claims 1,2 or 3, characterized in that the wells (10,10 ', 10 ") are produced by passing a machine provided with teeth (6), the teeth being assembled and mounted on a mobile support (7) animated by a cyclic movement allowing the penetration of the teeth (6) into the ground in a substantially linear movement along the axis of the teeth and, their lifting in an angular tilting movement capable of lifting the portion of the ground located behind the teeth relative to the direction of advance of the machine. 5 - Method according to one of claims 1 to 4, characterized in that prior to the formation of the wells by passage of the machine provided with the penetration and tilting teeth, sand (5) is poured which is spread over the ground, the sand being displaced, after passage of the perforating machine by displacement of a flexible support such as a net (9) suitable for driving the filling of the wells (10,10,10 ") by the sand and thus the fixing of the well in its structure thanks to the presence of filling sand. 6 - Sports field obtained by the implementation of the method according to one of claims 1 to 5 above, characterized in that it comprises parallel longitudinal trenches (1,1 ') filled with mineral aggregates and flush with the upper level of the ground, the strips of land located between two trenches being perforated and comprising micro-wells (10,10 ', 10 ") spaced substantially evenly and filled with sand. 7 - Sports ground according to claim 6, characterized in that the depth of the wells is substantially two thirds of the depth of the evacuation trenches. 8 - Sports field according to claim 6 or claim 7 above, characterized in that the surface layer is lightened and aerated by forming a network of horizontal capillary slots (2,2 ', 3,3'), thanks to a preliminary subsoiling work, this network of horizontal capillary slits joining the micro-wells (10,10 ', 1O ") between them and joining the micro-wells to the evacuation slits (1,1') and drainage the land comprising a surface protective layer comprising a high percentage of sand. 9 - Land according to one of claims 6,7 or 8, characterized in that the depth of the wells is between 10 and 30 cms and it is preferably between 12 and 20 cms.