EP3919696A1

EP3919696A1 - A modular block for filling underground basins and basin produced with these modular blocks

Info

Publication number: EP3919696A1
Application number: EP20178531.8A
Authority: EP
Inventors: Gabriele Andrighetti
Original assignee: Nowasteworld Srl
Current assignee: Nowasteworld Srl
Priority date: 2020-06-05
Filing date: 2020-06-05
Publication date: 2021-12-08

Abstract

The block made of plastic material (1) for filling underground basins (I) for storing rainwater or river water comprises a first plurality of hollow truncated-pyramid shaped bodies (3A), extending from a first side of a median plane (M) of the block and a second plurality of hollow truncated-pyramid shaped bodies (3B), extending from a second side of the median plane. The truncated-pyramid shaped bodies (3A, 3B) are configured to mutually superimpose the blocks with the smaller bases of the truncated-pyramid shaped bodies of one block resting on the smaller bases (5) of an adjacent block. Openings in the walls of the truncated-pyramid shaped bodies (3A, 3B) place the inner volumes of the truncated-pyramid shaped bodies (3A, 3B) of mutually superimposed blocks (1) in fluid communication in the position with maximum overall dimensions.

Description

TECHNICAL FIELD

The present invention relates to the production of hydraulic works aimed at reducing the risk of flooding. Embodiments described herein relate to modular blocks for producing underground basins for temporarily storing rainwater or river water.

BACKGROUND ART

In recent years, with extreme climate change, a number of natural disasters which have caused increasingly frequent and harmful severe flooding have occurred. By examining the statistics of the flood events that have occurred starting from 1900 to the present day, as published by Wikipedia, it is possible to note particularly significant and troubling values.
Firstly, the index of occurrence of the flood event, obtained by dividing the number of these events occurring over a ten-year period by the total in the same ten years, increases in value over time, reaching substantial numbers (more than double) in the last twenty-five years and have more than quadrupled in the last five years. These phenomena require an adaptation of the hydraulic network to reduce the risk of floods and limit their damages.
There are no easy solutions to this adaptation, above all for reasons linked to the high costs to be sustained and to the high environmental impacts, which the various approaches to the problem can cause. Some solutions possible with ordinary techniques are difficult to put in place. For example, building a new hydraulic network or even simply expanding the existing network has very high costs and above all is limited by highly urbanized and developed territories, where the availability of land that is undeveloped or without restrictions is very limited. Added to these factors are also serious problems of impact on the landscape.
Alternatively, extensive "reservoir" areas, can be produced, with basins in which to temporarily store rainwater or river water, so as to reduce the flow rate during periods of heavy rainfall. The water temporarily stored is subsequently drained away slowly once the rains decrease or cease. The identification, along the path of a river course, of large areas in which the excess waters of the water course can be temporarily stored and retained while waiting for the flood wave to pass, is a concrete alternative, with relatively low costs. Some important limits to this solution are that there can be no buildings in these areas, and also that is it not easily achievable in populated areas, where the need is often greater, as it is in these areas that rivers overflow their banks more frequently, due to the inadequacy of their hydraulic cross section.
Therefore, there is the need to find new solutions to the aforesaid problems.

SUMMARY

According to one aspect, there is provided a block made of plastic material, preferably recycled plastic, for filling underground storage basins for rainwater or river water. The block comprises a first plurality of hollow truncated-pyramid shaped bodies, extending from a first side of a median plane of the block, and a second plurality of hollow truncated-pyramid shaped bodies, extending from a second side of the median plane. Each truncated-pyramid shaped body has a larger base on the median plane and a smaller base at a distance from the median plane. The hollow truncated-pyramid shaped bodies are configured and arranged so that identical blocks can be mutually superimposed in two distinct positions, i.e.: in a position with minimum overall dimensions, in which truncated-pyramid shaped bodies of one block are inserted into truncated-pyramid shaped bodies of a superimposed block; and in a second position with maximum overall dimensions, in which truncated-pyramid shaped bodies of two superimposed blocks rest on one another at the respective smaller bases.
The truncated-pyramid shaped bodies have on the respective walls, and in particular on the wall defining the smaller base, openings to place the inner volumes of the pyramid shaped bodies of mutually superimposed blocks in fluid communication in the position with maximum overall dimensions.
By placing several modular blocks of this type horizontally side by side with one another side, to form a respective layer, and superimposing several layers on one another, arranged so that modular blocks of adjacent layers are arranged in the position with maximum overall dimensions, it is possible to obtain filling volumes of underground basins, containing a very high percentage of empty space, for example up to around 90%, which can be filled with rainwater and/or river water. The structure resulting from superimposing the layers of modular blocks also allows the basin to be covered with a layer of material suitable to reconstruct on top of the surface occupied by the basin, an area that can be used, for example, for agricultural or other purposes.
It is thus possible to produce, rapidly and with minimum costs, underground, or subterranean, basins, of large size, which represent watersheds for storing excess water that can be removed from a river or other water course, reducing its flow rate and consequently preventing flooding. In combination or alternatively, rainwater, i.e., storm water, can be stored in the basin. The basin is filled and emptied easily due to the structure of the modular blocks. The mechanical compression strength of the layers of superimposed modular blocks allows the surface above the basin to be used efficiently. This can thus be produced without sacrificing useful surface, for example to create green areas, car parks, cultivable areas, roads or other infrastructures.
According to a further aspect, a system for temporarily storing rainwater or river water is described, comprising: an underground basin for temporarily storing rainwater or river water; and at least one hydraulic connection for conveying water into the basin. The storage volume is filled with a plurality of modular blocks of the type defined above, and a covering resting on the filling blocks is formed above the volume of the basin, to form a usable area.
Further advantageous features and embodiments of the modular block and of the basin filled with the modular blocks are defined in the appended claims, which form an integral part of the present description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by following the description and the accompanying drawings, which illustrate a non-limiting example of embodiment of the invention. More in particular, in the drawing:

Fig. 1 shows an axonometric view of a modular block in an embodiment;
Fig.2 shows a plan view of the modular block of Fig. 1;
Fig.3 shows a section according to the line III-III of Fig.2;
Fig.4 shows an axonometric view of superimposed blocks;
Fig. 5 shows a cross section of modular superimposed blocks;
Fig.6 shows an enlargement of the detail VI of Fig.5;
Fig.7 shows a section of a portion of a basin filled with layers of modular blocks; and
Fig. 8 shows a schematic view of a basin associated with a water course.

DETAILED DESCRIPTION

A modular block for storage basins for temporarily storing or collecting river water or rainwater is represented in an axonometric view in Fig.1 and in a plan view in Fig.2. The block 1 is preferably made of molded plastic material. Advantageously, the plastic material can be recycled plastic material.
The modular block 1 comprises a first series or plurality of hollow truncated-pyramid shaped bodies 3A, which extends from a median plane with the trace M (see section of Fig.3) on one side of this median plane. On the opposite side of the median plane M a second series or plurality of hollow truncated-pyramid shaped bodies 3B extends. The hollow truncated-pyramid shaped bodies 3A, 3B have a quadrangular, and more precisely square, cross section. The truncated-pyramid shaped bodies are arranged in a checkerboard pattern, i.e., alternated. In substance, by observing the block 1 from above (Fig.2), 25 truncated-pyramid shaped bodies 3A are arranged on one side thereof, in rows alternately of three and four truncated-pyramid shaped bodies. The cavities that define the inner volume of the same number of truncated-pyramid shaped bodies 3B that protrude from the opposite side of the median plane M are inserted between them.
The total number of truncated-pyramid shaped bodies 3A, 3B is by way of example and it must be understood that modular blocks 1 of different sizes, with a different number of hollow truncated-pyramid shaped bodies, could also be produced.
Each hollow truncated-pyramid shaped body 3A, 3B has a larger base lying on the median plane M, and in practice consisting of the opening of the hollow compartment defined inside the hollow truncated-pyramid shaped body 3A, 3B. Moreover, each truncated-pyramid shaped body 3A, 3B has a smaller base, a distance from the median plane M, defined by a closing wall of the hollow truncated-pyramid shaped body 3A, 3B. The smaller bases of the truncated-pyramid shaped bodies 3A, 3B are indicated with 5. Lateral walls 7 defining the sides of each hollow truncated-pyramid shaped body 3A, 3B extend from the larger bases to the smaller bases.
In practice, as can be easily understood from the axonometric view of Fig. 1 and from the section of Fig.3, each block 1 consists mainly of a layer of shaped plastic material, which forms the lateral walls 7 and the smaller bases 5 of each truncated-pyramid shaped body. The thickness of the lateral walls 7 and of the smaller bases 5 of the hollow bodies 3A, 3B can be approximately constant, for example in the order of 5 mm.
The shape and alternated arrangement of the truncated-pyramid shaped bodies 3A, 3B is such as to allow superimposing of blocks 1 in a position with minimum overall dimensions, inserting the truncated-pyramid shaped bodies 3A of one block into the cavities defining the truncated-pyramid shaped bodies of a block above or below. In this way, the blocks 1 interpenetrate allowing a large number of blocks 1 to be stored and transported in a small volume.
Alternatively, the blocks 1 can be superimposed in the layout shown in the axonometric view of Fig.4 and in the sections of Figs. 5 and 6, with the truncated-pyramid shaped bodies 3A of one block placed opposite the truncated-pyramid shaped bodies 3B of a block above or below, arranging truncated-pyramid shaped bodies 3A, 3B in mutual opposition, resting on one another at the respective smaller bases 5. In this layout, a structure formed by layers of mutually superimposed blocks 1 occupies a very large and mostly empty volume due to the large empty space inside each hollow truncated-pyramid shaped body 3A, 3B.
To stack the modular blocks 1 in the position with maximum overall dimensions, with the smaller bases 5 opposite each other, the modular block 1 comprises mutual interlocking elements, associated with the smaller bases 5 of the single truncated-pyramid shaped bodies 3A, 3B.
In the illustrated embodiment, male and female elements are provided on each smaller base 5 of the truncated-pyramid shaped bodies 3A, 3B, destined to engage with one another when two blocks 1 are mounted superimposed in the position with maximum overall dimensions.
More in particular, in the illustrated embodiment each smaller base 5 of the hollow truncated-pyramid shaped bodies 3A, 3B comprises a pair of female elements 9 and a pair of male elements 11. These elements are arranged close to the four corners of the smaller base 5 of quadrangular shape. More specifically, the two female elements 9 are arranged closed to two corners along a first diagonal of the smaller base 5 and the male elements 11 are arranged close to the other two corners along the second diagonal of the smaller base 5.
As can be seen in particular in the enlarged section of Fig.6, the female element 9 is a through opening, which passes through the whole of the thickness of the smaller base 5. The male element 11 consists of a protrusion extending from the smaller base 5 outward. The male element 11 is apertured in 11A and can have a beveled outer edge 11B to facilitate insertion into the corresponding opening 9.
As can be easily understood from Figs. 5 and 6, when two blocks 1 are superimposed on one another with the male elements 11 inserted into the female elements 9, the two blocks 1 are stabilized relative to one another and cannot slide laterally. Moreover, the apertures 11A formed in the male elements 11 form passages that place the inner volumes of the single truncated-pyramid shaped bodies 3A, 3B in mutual fluid communication, for purposes that will be clarified below.
In some embodiments, reinforcing walls 15 can be provided inside the hollow truncated-pyramid shaped bodies 3A, 3B. As can be seen in particular in Figs.2 and 5, each wall 15 extends from the inner surface of the smaller base 5 toward the hollow inner volume of the respective truncated-pyramid shaped body.
In the illustrated embodiment, inside each hollow truncated-pyramid shaped body 3A, 3B there are four walls 15, each of which surrounds one of the openings 9 or one of the passages 11A of the male elements 11.
The walls 15 form ribs that increase the crush resistance of the single hollow truncated-pyramid shaped bodies 3A, 3B.
Possible methods of use of the above described modular blocks 1 are illustrated in particular in Figs. 7 and 8.
As is evident from the description above, with the modular blocks 1 it is possible to form layers of blocks, each comprising a plurality of coplanar blocks. In turn, the layers can be superimposed on one another so that the modular blocks 1 of each layer are arranged in a position with maximum overall dimensions with the modular blocks 1 of the adjacent layers, arranged with the smaller bases 5 of the single hollow truncated-pyramid shaped bodies resting on one another and with the male and female elements 9, 11 interlocked with one another.
By arranging layers of modular blocks 1 superimposed in this manner it is possible to occupy large volumes, a small part of which will be filled by the plastic forming the modular blocks 1 while the majority will be formed of the cavities of the hollow truncated-pyramid shaped bodies 3A, 3B. Advantageously, the thickness of the walls 5, 7 that define the single hollow truncated-pyramid shaped bodies 3A, 3B, and the elements 11 and the reinforcing walls or ribs 15 can be such that the total volume of plastic is around 1/10 of the total volume occupied by the layers of superimposed modular blocks 1 in the layout with maximum overall dimensions.
The modular blocks 1 can thus be used as filling material of an underground, or subterranean, basin I, as shown schematically in Fig.7. The underground basin I is filled with layers of superimposed modular blocks 1, which rest on a base B forming the bottom of the basin. A covering, which can for example be formed of a layer S1 of soil, which forms a useful surface S, is created above the layers of modular blocks 1. As a function of the type of material used to create the covering S1, the useful surface S can have different uses. In the example of Fig.7, the layer S1 formed of soil can form a cultivable area, destined for grazing land, a wooded area, or a public park.
In other embodiments, the underground basin I can be closed at the top with a material intended to form an area useful for other purposes, for example a car park.
The truncated-pyramid shaped structure of the hollow bodies 3A, 3B and the reinforcing walls or ribs 15 give the structure formed by the layers of modular blocks 1 high crush resistance, such that the covering S1 can be formed of even a very thick layer.
If useful or necessary, the layer S1 can be composite, and have a lower substrate S2 in contact with the top layer of modular blocks 1. The substrate S2 can, for example, be created with a material suitable to prevent soil from penetrating the basin filled with the modular blocks 1 below. Similar solutions can be used on the bottom of the basin I, with a substrate S3.
Due to the fact that around 90% of the volume of the underground basin I is empty, it has the capacity to store a large amount of water, for example rainwater or river water, diverted from a water course as will be better described below with reference to Fig.8.
The openings 9 and 11A place the single inner volumes of the truncated-pyramid shaped bodies 3A, 3B in fluid communication, so that the water can easily fill the whole of the hollow volume of the hollow truncated-pyramid shaped bodies 3A, 3B.
In some embodiments, not shown, a faster flow of water can be obtained by also producing openings in the lateral walls 7 defining the sides of the hollow truncated-pyramid shaped bodies 3A, 3B.
Fig.8 schematically shows the arrangement of an underground basin I, associated with a water course F. The underground basin I can be connected to the water course F by means of one or more hydraulic connections 21, 23. Apparatus to regulate the flow of water into and out of the underground basin I can be arranged along the hydraulic connections 21 and 23. In the illustrated embodiment, two hydraulic connections are provided, connected to the water course F in two points, one upstream and the other downstream, respectively. In the event of a flood, water can be diverted from the water course F toward the underground basin I by means of the hydraulic line 21, to reduce the flow rate downstream, and reduce or prevent the risk of flooding. After the flood wave has passed by, the water temporarily stored in the basin I can be drained away gradually by means of the second hydraulic connection 23 back into the water course F. Suitable bulkheads can be provided in 25 and 27 to regulate water flow.
In some embodiments, water lifting stations can be provided at the inlet and/or outlet. The use of these lifting stations can be provided as a function of the height at which the entry and exit points of the hydraulic lines are located relative to the basin. For example, a lifting station can be provided on the outflow hydraulic line 23.
Although two distinct hydraulic lines 21, 23 are provided in Fig.8, it would also be possible to provide a single hydraulic line, both for conveying the water into the basin I, and for outflow therefrom. In this case, it is more probable that a water lifting station will be required to empty the basin.
It would also be possible for the basin to be connected to more than two hydraulic lines, for example connected to more than one water course or connected in several points of the same water course, according to specific needs and to the morphology of the territory.
From the above description, it is clear that the modular block has a particular shape that allows total reversibility. In other words, each load bearing surface is similar to the opposite one. This result is obtained by mutually intersecting no. 50 hollow truncated-pyramid shaped bodies 3A, 3B (25 on each side of the median plane M). Each modular block 1 has an extremely compact load-bearing structure, capable of distributing the static load. With suitably dimensioning of the modular blocks 1 it is possible to achieve, for example, tensile strengths in the order of 15 tons per square meter without deformations of the modular blocks 1.
With modules of 1.2 m per side and heights of 0.35 m and wall thicknesses of around 5mm it is possible to obtain basin volumes of around 0.5 m³ for each block 1. Due to the extremely rapid assembling of the modular blocks 1 side by side with, and superimposed on, one another in a layout with maximum overall dimensions, it is possible to fill large underground basins in a very short time, with a structure that is substantially 90% empty and hence able to collect large amounts of water and at the same time provide a usable covering surface. The tapered shape of the truncated-pyramid shaped bodies and their alternated arrangement allow the modular blocks 1 to be stacked in a layout with minimum overall dimensions in which the pitch between superimposed blocks can be around 80 mm, for instance.
With the aforesaid dimensions, each modular block can have a weight in the order of 30-35 kg, which makes the block very easy to handle.
The filling structure of the underground basin formed by the superimposed layers of modular blocks 1 has a high draining capacity due to the fact that the whole structure is in suitable mutual communication, with wide passages both on the surfaces resting on the ground and on the load-bearing surfaces. The draining capacity can be increased by providing slots or openings (not shown) on the lateral walls 7 of the truncated pyramid shaped bodies 3A, 3B. These slots or openings can be obtained via the mold during the injection molding step. These features facilitate the inflow/outflow of rainwater or flood water in the event of flooding of the river courses.
In summary and in conclusion, the described modular block 1 allows a plurality of advantages to be obtained, including:

low cost of the raw material used (otherwise unusable plastic waste);
easy, rapid and inexpensive production, due to the use of multiple cavity molding systems;
high load-bearing capacity, lightness and draining capacity;
stackable to reduce transport costs, up to around 20 times less relative to the transport costs of conventional stone materials;
ease of handling, rapid and flexible use.

Claims

A block made of plastic material (1) for filling underground basins (I) for storing rainwater or river water; said block (1) comprising: a first plurality of hollow truncated-pyramid shaped bodies (3A), extending from a first side of a median plane (M) of the block; a second plurality of hollow truncated-pyramid shaped bodies (3B), extending from a second side of the median plane;
- wherein each truncated-pyramid shaped body (3A, 3B) has a larger base on the median plane and a smaller base (5) at a distance from the median plane (M);

- wherein the hollow truncated-pyramid shaped bodies (3A, 3B) are configured and arranged so that identical blocks can be mutually superimposed:

in a first position with minimum overall dimensions, wherein truncated-pyramid shaped bodies (3A, 3B) of a block (1) are inserted into truncated-pyramid shaped bodies (3A, 3B) of a superimposed block (1);

in a second position with maximum overall dimensions, wherein truncated-pyramid shaped bodies (3A, 3B) of two superimposed blocks rest on one another at the respective smaller bases (5);

- and wherein the truncated-pyramid shaped bodies (3A, 3B) have on the respective walls (5, 7) through openings (9, 11A) to place the inner volumes of the truncated-pyramid shaped bodies (3A, 3B) of mutually superimposed blocks (1) in fluid communication in the position with maximum overall dimensions.
The block (1) of claim 1, wherein the truncated-pyramid shaped bodies (3A, 3B) have a quadrangular, and in particular square, cross section.
The block (1) of claim 2, wherein the truncated-pyramid shaped bodies (3A, 3B) are distributed in a checkerboard pattern, so that the truncated-pyramid shaped bodies (3A, 3B) protruding from one side of the median plane (M) are arranged alternately with cavities defined by the truncated-pyramid shaped bodies (3B, 3A) protruding from the opposite side of the median plane (M).
The block (1) of one or more of the preceding claims, wherein each truncated-pyramid shaped body (3A, 3B) has openings (9, 11A) on the respective smaller base (5).
The block (1) of one or more of the preceding claims, wherein each truncated-pyramid shaped body (3A, 3B) has on the smaller base (5) mutual interlocking elements (9, 11), configured so as to mutually couple when two blocks (1) are superimposed in a position with maximum overall dimensions.
The block (1) of claim 5, wherein the interlocking elements (9; 11) configure openings (9; 11A) that place the inner volume of truncated-pyramid shaped bodies (3A, 3B) superimposed and coupled by means of said interlocking elements (9; 11) in fluid communication.
The block of one or more of the preceding claims, wherein each truncated-pyramid shaped body (3A, 3B) comprises, on the wall defining the smaller base (5), a pair of through openings (9) and a pair of apertured protrusions (11), arranged so that, when truncated-pyramid shaped bodies (3A, 3B) are superimposed in a position with maximum overall dimensions of the respective blocks, the pervious protrusions (11) of one block are inserted into the through openings (9) of the superimposed block (1).
The block (1) of claim 7, wherein each smaller base (5) of the truncated-pyramid shaped bodies (3A, 3B) is provided with two through openings (9), close to the two diagonally opposite corners of the smaller base (5) and two pervious protrusions (11), close to the other two diagonally opposite corners, said smaller base (5) having a quadrangular, and in particular square, shape.
The block (1) of one or more of the preceding claims, wherein the truncated-pyramid shaped bodies (3A, 3B) have through openings on respective lateral walls (7) extending from the larger base to the smaller base (5).
The block (1) of one or more of the preceding claims, wherein reinforcing walls (15), preferably orthogonal to the respective smaller base (5), are provided inside each truncated-pyramid shaped body (3A, 3B).
The block (1) of claim 10, wherein the reinforcing walls (15) surround openings (9; 11A) formed in the smaller base (5) of the respective truncated-pyramid shaped body (3A, 3B).
The block (1) of one or more of the preceding claims, wherein the plastic material defining said block (1) is distributed so that, in the position with maximum overall dimensions, no more than 15%, preferably no more than 12% of a total volume of superimposed blocks is occupied by the plastic material forming the blocks.
A system for temporarily storing river water or rainwater, comprising: an underground basin (I) for temporarily storing river water or rainwater; and at least one hydraulic connection (21; 23) for conveying water into the basin; wherein the basin is filled at least partially with a plurality of blocks (1) according to one or more of the preceding claims, on which a covering (S1, S2) resting on the filling blocks (1) is formed, said covering forming a usable area.
The system of claim 13, wherein the usable area is a cultivable area, a covering comprising a layer of soil being formed on said blocks.
The system of claim 13 or 14, comprising at least one of the following features: a second hydraulic connection (23; 21) for the outflow of water from the basin; a lifting station of the water from the basin; a bulkhead (25, 27) on at least one of said hydraulic connections.