Patent Grant
11479930
The invention relates to apparatus and methods of reducing and reversing soil erosion, and more particularly to apparatus and methods for capturing and retaining soil and debris carried by mudslides.
During intense forest fires, a waxy substance derived from the burning plant material is formed. Initially created as a gas, this substance penetrates into the soil and then hardens, creating what is called a hydrophobic layer beneath the upper layers of soil. This hydrophobic layer prevents water from sinking deeply into the soil, such that when rain falls heavily onto a mountain or other sloping surface after a forest fire, the rain water has no choice but to flow downhill on and near the surface of the soil, typically carrying with it soil and debris. The result is what is commonly referred to as a mudslide. Mudslides can also occur on a slope that has been subjected to unusually heavy rainfall over an extended period of time, even if the slope has not experienced a forest fire.
Attempts to mitigate the occurrence of mudslides on hills and mountains typically involve placing logs, cement barriers, or other heavy blocking objects in the paths of potential or actual mudslides. However, this approach is often impractical, due to the logistic difficulties of transporting very heavy objects to what are often remote locations. Furthermore, this approach is sometimes ineffective, due to the very large amount of energy that can be carried by a mudslide, which can cause the mudslide to simply push the log, cement barrier, or other blocking object out of the way, or carry it downhill with the mudslide.
In principle, mudslides can be mitigated by terraforming of the terrain using heavy equipment, so that barriers are formed against mudslides, and so that any hydrophobic layer is broken up and removed. However, this approach is not always practical, due at least to the inaccessibility of the mudslide area to heavy equipment, and due to a desire not to create unnatural structures in wilderness and forest areas.
What is needed, therefore, is an apparatus and method for mitigating soil erosion caused by mudslides, where the apparatus is relatively light in weight, easy and inexpensive to transport and install, and easy to remove and relocate after natural regrowth of vegetation has broken through the hydrophobic layer, stabilized the soil, and reduced the likelihood of mudslides.
The present invention is a barrier structure and method of use thereof for mitigating soil erosion caused by mudslides, where the barrier structure is relatively light in weight, easy and inexpensive to transport and install, and easy to remove and relocate after natural regrowth of vegetation has broken through any hydrophobic layer, stabilized the soil, and reduced the likelihood of mudslides.
Rather than providing a barrier having an intrinsically high mass, such as a concrete barrier or large log, the present invention is configured to increase its effective weight naturally, after installation, by accumulating soil and/or water within its interior, so that the mass of the accumulated soil and/or water stabilizes the barrier structure and enables it to resist the oncoming force of a mudslide. Once the barrier structure is filled and stabilized, additional soil, debris and other materials will typically accumulate in front of the barrier structure and function as an additional barrier that helps to mitigate and deflect the energy of mudslides. Accordingly, the disclosed barrier structure functions in a manner similar to a concrete barrier or log, but is far lighter in weight and easier to transport and remove.
The present invention is specifically configured for use on sloping ground, i.e. ground that is inclined at an angle of inclination from horizontal. The term “slope normal” is used herein to refer to a direction that is perpendicular to the sloping ground. Surfaces having inclinations that are greater than the inclination of the sloping ground are referred to herein as being “inclined downhill,” while surfaces having inclinations that are less than the inclination of the sloping ground are referred to herein as being “inclined uphill.” It should also be noted that the term “soil” is used herein generically to refer to all relatively small particulates, such as grains of sand and particles of organic matter, that are carried by water in a mudslide, while the term “debris” is used herein generically to refer to any and all relatively large objects, such as brush, tree branches, and rocks, that may also be propelled downhill by a mudslide.
The disclosed barrier structure includes a barrier apparatus that comprises a rigid or semi-rigid barrier wall. The barrier wall is inclined downhill and is penetrated by a plurality of large holes, so that when a mudslide impacts the barrier wall, the mud is directed upward across the front surface of the barrier wall, causing at least some of the mud to enter through the holes into an interior of the barrier apparatus behind the barrier wall, while the larger debris either accumulates uphill of the semi-rigid barrier or flows over the top thereof.
The barrier apparatus further comprises a rear wall that is inclined uphill, and, in embodiments, also a floor and/or one or two side walls, which create a semi- or fully enclosed interior within which the entrained soil within the captured mud settles and separates from the water. Small holes, which are smaller than the large holes, are provided in the rear wall and, in embodiments, in at least one side wall, so that water that has separated from the soil within the interior of the barrier apparatus can drain out and continue to flow downstream, while soil continues to accumulate. In embodiments, the small holes are offset from the base of the sand-collecting barrier apparatus, so as to encourage pooling of mud, whereby the entrained soil has time to settle out and accumulate before the water rises high enough to drain out through the small holes.
In embodiments, the disclosed barrier structure further includes an underlying reservoir that is configured to capture water and/or mud as it flows over the top of the barrier and/or out from the small holes in the rear wall, thereby rapidly increasing the mass of the barrier so that it remains stable while it collects mud within its interior and separates the soil from the water. For example, the underlying reservoir may fill with rain during a heavy rainfall that is followed by a mudslide. In some embodiments, the overlying elements of the barrier apparatus are attachable to and detachable from the underlying reservoir. In other embodiments, the underlying water reservoir is inseparable from the remainder of the barrier apparatus.
In some embodiments, the weight of the collected soil and/or water is sufficient by itself to stabilize the barrier apparatus and enable it to resist mudslides. Other embodiments include an anchoring feature, such as anchor stakes that can be driven into the underlying ground to further stabilize the barrier apparatus against being dislodged by mudslides.
So as to resist the energy of larger mudslides, some embodiments of the disclosed barrier apparatus include a passage that penetrates the barrier apparatus and allows a portion of the impacting mud to flow through the barrier apparatus largely unimpeded, thereby reducing the energy that is applied to the barrier apparatus. Additionally, mud from larger mudslides can flow over the top of the barrier wall, further limiting the fractional amount of mudslide energy that is applied to the barrier apparatus.
In embodiments, the barrier structure further includes a diverting wedge located uphill of the barrier apparatus, and configured as a pair of joined diverting walls that are penetrated by wedge holes and share a common uphill edge. The diverting walls are thereby configured as a wedge that re-directs and diverts incoming debris, and some incoming mud, to either side of the barrier apparatus, while allowing a remainder of the mud to pass through the wedge holes and flow on, with reduced energy, to the barrier apparatus. In various embodiments, the diverting walls include downhill panels that extend to the barrier wall, so that the diverting wedge is stabilized by the mass of collected materials within the barrier apparatus.
In various method embodiments, a plurality of the disclosed barrier structures are implemented to mitigate mudslides, extending from at least one uphill barrier structure to at least one downhill barrier structure, whereby a mudslide serially encounters the plurality of barrier structures as it flows downhill. According to this approach, each of the barrier structures is required to withstand only a fraction of the total mudslide energy, while additional mud flowing through, around, and/or over the barrier structure continues downhill to the next barrier structure in the series. For example, the one or more uphill barrier structures can include deflecting wedges, while the one or more downhill barrier structures are able to resist the remaining energy of a mudslide without requiring deflecting wedges.
In some embodiments, the barrier wall extends above the rear wall, and in some of these embodiments the barrier structure further includes a backstop wall that is provided behind the rear wall, and extends to a point above the top of the rear wall, so that an additional soil collecting chamber is formed between the backstop wall and the rear wall. In these embodiments, the backstop wall is also penetrated by small holes. Some of these embodiments include an underlying reservoir that extends beyond and behind the backstop wall, so that an open region of the underlying reservoir is positioned to receive water that flows out through the small holes provided in the backstop wall, as well as any mud that flows over the top of the barrier wall.
Various embodiments include a soil-collecting extension that can be coupled to the barrier apparatus and underlying water reservoir (if any). The soil-collecting extension includes a top that is penetrated by extension holes, which in embodiments are larger than the “large” holes of the barrier wall. The top of the soil-collecting extension is substantially parallel to the underlying slope, and extends to the upper edge of the barrier wall, so that energetically flowing mud that flows over the top of the barrier wall is caused to flow across the top of the soil-collecting extension, whereupon some of the mud falls through the extension holes and into an interior of the soil-collecting extension. It will be noted that the soil-collecting extension is also sometimes referred to herein simply as the “extension.”
The interior of the soil-collecting extension is bounded by a rear wall of the extension and, in embodiments, by two side panels of the extension. The front of the extension is open, so that the top of the soil-collecting extension can extend to the top of the barrier wall. When the extension is attached to the barrier wall, the rear wall or backstop wall becomes the front boundary of the extension interior.
As water and soil fall into the interior of the extension, the soil settles and separates from the water. As the level of water above the soil rises, the water is able to flow through holes or other openings provided in the rear wall of the extension.
Embodiments of the disclosed barrier structure are constructed from plywood, from metal, from a plastic such as acrylic, from fiberglass, from particle board, which may include a laminated coating or veneer, from micro-lattice, from rigid foam, from Styrofoam, from graphene, and/or from any other suitable material. Some embodiments are constructed using bio-degradable materials, such as AshCrete, hemperete clay, Timbercrete, bamboo, recycled wood, and other recycled materials, so that it is not necessary to remove the barriers after the danger of mudslides has abated.
Embodiments of the barrier apparatus that require enhanced structural strength include internal partition walls that extend between and reinforce the barrier wall and rear wall. The partition walls are penetrated by additional, large interior holes, so that mud that enters through the large holes provided in the barrier wall is able to flow downward through the interior holes to the bottom of the apparatus interior. Embodiments further include at least one support wall within the underlying water reservoir that helps to support the weight of the overlying portions of the apparatus, especially as the interior of the apparatus fills with deposited soil. The support walls are also penetrated by holes, so that water is able to flow freely within the underlying reservoir.
In some embodiments, additional support walls are included within the interior of the soil-collecting extension so as to provide extra support to the top of the extension.
A first aspect of the present invention is a barrier structure for reducing erosion due to mudslides on a slope having a slope direction that is inclined at a slope inclination angle. The barrier structure comprises a barrier apparatus that includes a barrier wall having a top and a bottom, the barrier wall being inclined at an angle that exceeds the slope inclination angle by least 20 degrees, a first plurality of holes penetrating the barrier wall, a rear wall having a top and a bottom, the rear wall being inclined at an angle that is less than the slope inclination angle, the rear wall being located behind the barrier wall with the top of the rear wall extending to an upper region of the barrier wall so that a chamber space is formed between and bounded by the barrier wall and the rear wall, and a second plurality of holes penetrating the apparatus rear wall, the holes of the second plurality of holes being smaller in diameter than the holes of the first plurality of holes, the first plurality of holes being configured to allow mud to flow through the barrier wall and into the chamber space, and the second plurality of holes being configured to allow water to flow through the apparatus rear wall out of the chamber space.
In embodiments, the chamber space is further bounded by at least one side wall.
Any of the above embodiments can further include an underlying water reservoir located beneath the chamber space and fixed to the barrier wall and apparatus rear wall, the underlying water reservoir being configured to receive and be filled with at least one of mud and water that flows through the second plurality of holes out of the chamber space or over the top of the barrier wall.
Any of the above embodiments can further include a barrier extension comprising an extension top penetrated by a third plurality of holes, and an extension rear wall extending downward from a rear edge of the extension top, a front edge of the extension top being configured to abut the top of the barrier wall when the sand-collecting extension is installed behind the sand-collecting apparatus, such that mud flowing over the top of the barrier wall flows across the extension top. In some of these embodiments, the barrier extension further comprises a pair of opposing extension side walls.
In any of the above embodiments, all components of the barrier structure can be made from biodegradable materials
Any of the above embodiments can further include a plurality of anchoring stakes configured to anchor the barrier structure to the slope.
In any of the above embodiments, the barrier wall and rear wall can be pivotable about their bottoms so as to overlap with each other in a substantially flat, folded configuration.
In any of the above embodiments, the barrier apparatus can further comprise an open passage that penetrates through the barrier apparatus and is configured to allow a fraction of mud impacting the barrier wall to proceed past the barrier apparatus substantially unimpeded by the barrier apparatus.
Any of the above embodiments can further include a diverting wedge extending uphill from the barrier wall, the diverting wedge comprising a pair of diverting walls that are penetrated by a fourth plurality of holes, the diverting walls being inclined toward each other at substantially equal and opposite angles relative to the slope direction so that they meet at a common uphill edge, the diverting wedge being configured to allow some mud from a mudslide to pass through the fourth plurality of holes and continue to the barrier wall, while diverting a remainder of mud and debris of the mudslide to either side of the barrier wall.
A second general aspect of the present invention is a method of reducing erosion due to mudslides on a slope having a slope direction that is inclined at a slope inclination angle. The method includes providing a barrier structure according to any embodiment of the first general aspect, installing the barrier structure on a slope that is subject to mudslides, allowing mud to flow through the barrier wall and into the chamber space, allowing water included in the mud within the chamber space to separate from soil included in the mud within the chamber space, and allowing the water within the chamber space to flow out of the chamber space through the second plurality of holes, while the soil within the chamber space is retained therein, the retained soil thereby being added to the effective weight of the barrier apparatus and thereby increasing a stability of the barrier structure.
Some of these embodiments further include, after a danger of mudslides has abated, emptying the retained soil from the barrier chamber and removing the barrier apparatus from the slope.
In any of the above embodiments, the barrier structure can be constructed from biodegradable materials, and the method can further include, after a danger of mudslides has abated, allowing the barrier structure to decompose into the slope
In any of the above embodiments, the barrier structure can further include a diverting wedge extending uphill from the barrier wall, the diverting wedge comprising a pair of diverting walls that are penetrated by a fourth plurality of holes, the diverting walls being inclined toward each other at substantially equal and opposite angles relative to the slope direction, so that they meet at a common uphill edge, and the method can further include causing the diverting wedge to allow some mud from a mudslide to pass through the fourth plurality of holes and continue to the barrier wall, while diverting a remainder of mud and debris of the mudslide to either side of the barrier wall.
A third general aspect of the present invention is a method of reducing erosion due to mudslides on a slope having a slope direction that is inclined at a slope inclination angle. The method includes installing a plurality of barrier structures on the slope, the plurality of barrier structures comprising at least one uphill barrier structure that is uphill of at least one downhill barrier structure, each of the uphill and downhill barrier structures being barrier structures according to any embodiment of the first general aspect. The method further includes allowing mud from a mudslide to impact the uphill barrier structure such that a first portion of the mud enters the chamber space of the uphill barrier structure while a second portion of the mud passes over, around, or through the uphill barrier structure, and allowing the second portion of the mud to impact the downhill barrier structure.
In embodiments, the uphill barrier structure includes at least one of an open passage that penetrates through the barrier apparatus of the uphill barrier structure and is configured to allow at least some of the second portion of the mud to proceed past the uphill barrier apparatus substantially unimpeded by the uphill barrier apparatus, and a diverting wedge extending uphill from the barrier wall of the uphill barrier structure, the diverting wedge comprising a pair of diverting walls that are penetrated by a fourth plurality of holes, the diverting walls being inclined toward each other at substantially equal and opposite angles relative to the slope direction so that they meet at a common uphill edge, the diverting wedge being configured to allow the first portion of the mud to pass through the fourth plurality of holes and continue to the barrier wall, while diverting at least part of the second portion of the mud to either side of the barrier wall.
In any of the above embodiments, the downhill barrier structure can include neither of an open passage and a diverting wedge.
The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.
The present invention is a barrier structure and method of use thereof for mitigating soil erosion caused by mudslides, where the barrier structure is relatively light in weight, easy and inexpensive to transport and install, and easy to remove and relocate after natural regrowth of vegetation has broken through the hydrophobic layer, stabilized the soil, and reduced the likelihood of future mudslides.
Rather than providing a barrier having an intrinsically high mass, such as a concrete barrier or large log, the present invention is configured to be initially light in weight, and to naturally increase its effective weight after installation by accumulating soil and/or water within its interior, so that the mass of the accumulated soil and/or water stabilizes the barrier structure and enables it to resist the oncoming force of a mudslide. Once the barrier structure is filled and stabilized, additional soil, debris and other materials accumulate in front of the barrier structure and function as an additional barrier that helps to mitigate and deflect the energy of mudslides. Accordingly, the disclosed barrier structure functions in a manner similar to a concrete barrier or log, but is far lighter in weight and easier to transport and remove.
The present invention is specifically configured for use on sloping ground, i.e. ground that is inclined at an angle of inclination from horizontal. The term “slope normal” is used herein to refer to a direction that is perpendicular to the sloping ground. Surfaces having inclinations that are greater than the inclination of the sloping ground are referred to herein as being “inclined downhill” while surfaces having inclinations that are less than the inclination of the sloping ground are referred to as being “inclined uphill.” It should also be noted that the term “soil” is used herein generically to refer to all relatively small particulates, such as particles of sand and organic matter, that are suspended within and carried by water in a mudslide, while the term “debris” is used herein generically to refer to any relatively large objects, such as brush, tree branches, and rocks, that may also be propelled downhill by a mudslide.
With reference to
The barrier apparatus 100 further comprises a rear wall 112 and, in embodiments, also one or two side walls (812 in
It should be noted that, while most embodiments of the present invention are intended for installation on sloping ground, for ease of illustration the remaining figures presented herein after
Some embodiments are sufficiently heavy and sturdy to withstand the impact of mudslides and to remain in position without anchoring, while other embodiments include an anchoring feature. The embodiment of
Certain embodiments can be easily disassembled and/or folded for transport and for storage. With reference to
In the embodiment of
A front-left perspective view of the embodiment of
Embodiments of the disclosed apparatus are constructed from panels 102, 112, 120 any or all of which can range in thickness between one quarter of an inch and two inches in thickness. In some embodiments, any or all of the panels 102, 112, 120 are between one quarter of an inch and one inch in thickness. In other embodiments, any or all of the panels 102, 112, 120 are between 1/32 inch and 12 inches thick.
In various embodiments, any or all of the panels 102, 112, 120 are sheets made from plywood, from metal, from a plastic such as acrylic, from fiberglass, from particle board, which may include a laminated coating or veneer, from micro-lattice, from rigid foam, from Styrofoam, from graphene, and/or from some other suitable material. Some embodiments are constructed using bio-degradable materials such as AshCrete, hemperete clay, Timbercrete, bamboo, recycled wood, and other recycled materials, so that it is no necessary to remove the barriers after the danger of mudslides has abated. Some embodiments include a bottom panel 120, while others do not.
With reference to
In the embodiment of
In the embodiment of
A front-left perspective view of the embodiment of
With reference to
With reference to
The interior 506 of the barrier extension 500 in the embodiment of
As mud falls through the extension holes 504 into the interior 506 of the extension 500, the entrained soil 512 settles and separates from the water 514. As the level of water 514 above the soil 512 rises, the water 514 is able to flow over the rear wall 510 of the underlying reservoir 110 through a screen 518 and into the underlying reservoir 110. In the embodiment of
In
It will be noted that
With reference to
Additionally, mud from larger mudslides can flow over the top of the barrier wall, further limiting the fractional amount of mudslide energy that is applied to the barrier apparatus.
With reference to
As can be seen in the top view of
With reference to
With reference to
It should be noted that the term “barrier structure” is used herein to refer to the entire structure that is implemented to block mudslides, whereas the term “barrier apparatus” is used herein to refer specifically to the structure that includes a barrier wall 102, a rear wall 112, and possibly a backstop wall. Any given barrier structure will include a barrier apparatus, and may also include, in any combination, an underlying reservoir, a rear extension, and/or a deflecting wedge.
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. Each and every page of this submission, and all contents thereon, however characterized, identified, or numbered, is considered a substantive part of this application for all purposes, irrespective of form or placement within the application.
The invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein and is not inherently necessary. However, this specification is not intended to be exhaustive. Although the present application is shown in a limited number of forms, the scope of the invention is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof. One of ordinary skill in the art should appreciate after learning the teachings related to the claimed subject matter contained in the foregoing description that many modifications and variations are possible in light of this disclosure. Accordingly, the claimed subject matter includes any combination of the above-described elements in all possible variations thereof, unless otherwise indicated herein or otherwise clearly contradicted by context. In particular, the limitations presented in dependent claims below can be combined with their corresponding independent claims in any number and in any order without departing from the scope of this disclosure, unless the dependent claims are logically incompatible with each other.
This application is a continuation in part of U.S. application Ser. No. 17/179,048 filed on Feb. 18, 2021. Application Ser. No. 17/179,048 is a continuation in part of U.S. application Ser. No. 16/904,047 filed on Jun. 17, 2020, now U.S. Pat. No. 10,954,641. U.S. application Ser. No. 16/904,047 is a continuation in part of U.S. application Ser. No. 16/480,476, filed on Jul. 24, 2019, now U.S. Pat. No. 10,718,095. Application Ser. No. 16/480,476 is a national phase application of PCT application PCT/US2018/012781, filed on Jan. 8, 2018. Application PCT/US2018/012781 claims the benefit of U.S. Provisional Application No. 62/451,394, filed Jan. 27, 2017. All of these applications are herein incorporated by reference in their entirety for all purposes.
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| Number | Date | Country | |
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| Number | Date | Country | |
|---|---|---|---|
| Parent | 17179048 | Feb 2021 | US |
| Child | 17481801 | US | |
| Parent | 16904047 | Jun 2020 | US |
| Child | 17179048 | US | |
| Parent | 16480476 | US | |
| Child | 16904047 | US |
