GB2571719A - Foundation system - Google Patents

Abstract

The present invention relates to a foundation system and a method of constructing a foundation system in a swale. A plurality of permeable structures 104 which maybe in the form of a gabion wall, are provided on the base 110 of the swale to separate the swale into a plurality of plots, and a buoyant foundation 202 is positioned on the base of the swale within a permeable structure. A reinforcing structure 106 may be provided on the base and a raft provided on the foundation. Guide piles may be provided in the base of the swale.

Description

(57) The present invention relates to a foundation system and a method of constructing a foundation system in a swale. A plurality of permeable structures 104 which maybe in the form of a gabion wall, are provided on the base 110 of the swale to separate the swale into a plurality of plots, and a buoyant foundation 202 is positioned on the base of the swale within a permeable structure. A reinforcing structure 106 may be provided on the base and a raft provided on the foundation. Guide piles may be provided in the base of the swale.

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Foundation System

Field of disclosure [0001] The present invention relates generally to a foundation system and a method of constructing a foundation system in a swale, or directly on ground which has been scraped back, cut and filled. With the present invention, foundations for structures can be built in areas at risk of flooding.

Background [0002] With growing populations, the need for housing is constantly increasing. However, the location in which housing can be built can be restricted by various factors, whether political (e.g. protect environmental sites), geographical (e.g. rugged ground or unstable ground), or economic (e.g. a desire to live in areas in which employment can be found). In some cases, the restriction is a combination of factors.

[0003] Taking, for example, a geographical area encompassing a river; it is not possible to use the same building techniques for dry land if it is desired to build closer to the river. Instead, buildings closer to the river may have to be raised on stilts, such as can be seen with piers. Additionally, a government may prevent building within the flood plain of the river for safety reasons, unless specific measures are taken. Broadly, these measures fall into two categories: flood resilience and flood resistance.

[0004] Flood resilience limits damage once a flood does occur. For example, when considered on the scale of villages, towns and cities, barriers may be erected to direct water away from buildings (i.e. directing the flood along a road). When considered on the scale of individual buildings, flood mitigation measures may include placing all electrical sockets and/or wiring above a certain height, or using stone, tile or hardwood flooring in the lower storeys of the building.

[0005] Flood resistance seeks to stop, or reduce the chance of, a flood from occurring in an area the first place. On a countrywide, or ‘mass development’, scale, these flood prevention measures include coastal/river defences, dams, diversion canals or ‘swales’, flood plains and flood barriers, amongst others. On the scale of an individual building, sandbags can be used to prevent water entering the building, buildings can be raised on stilts, etc.

[0006] With such mass development scale flood resistance measures, however, flood water is typically displaced to alternate sites to avoid flooding a developed site (i.e. a site with buildings and infrastructure thereon). For example, building a dam to prevent excess water flowing along a river toward a built-up site causes land up-stream of the dam to flood instead. Similarly, a swale can be thought of as a sacrificial site to hold excess water from a river to prevent a developed site from flooding. A manmade swale may be dug upstream of a built-up site to provide an area to hold a quantity of water thereby preventing that quantity of water from flowing downstream toward the developed site. However, simply displacing the water this this way is not always satisfactory as it prevents other sites from being used for building, and can cause environmental damage to those other sites, which become more prone to flooding.

[0007] Instead of displacing water, permanent static elevation of buildings can be utilised. The building is raised above the water level even during a flood event, but infrastructure can be difficult to accommodate. For example, a building on stilts would be above a level of a road. During a flood event, therefore, the building may not flood but transportation, and particularly emergency services, may be hindered. Furthermore, the static nature of fixed stilts may mean that in future, given climate change, water levels may rise higher than desired and flood the property.

[0008] The ‘Formosa’ house, created by Baca Architects (http://www.baca.uk.com/portfolio/amphibious), incorporates a buoyant foundation that allows a building to float as water level rises. The building rests on the ground on fixed foundations but, whenever a flood occurs, rises up in its dock and floats there buoyed by the floodwater. The house is fixed to a concrete foundation block that is recessed into the ground under normal conditions. During a flood event, the house rises with the flood water. However, it would take time for water in the dock of the ‘Formosa’ house to drain and therefore the house would remain in a raised configuration even after a flood event. Moreover, infrastructure around the ‘Formosa’ house would still be submerged and potentially damaged during a flood event. Given the incorporation of a costly and complex dry dock system this design is not appropriate for large scale volume house-building which requires simplicity and ease of replication.

[0009] There remains a need for a system that allows buildings or structures built on a site at risk of flooding to be protected without increasing the risk of flooding in neighbouring sites and with minimal disruption to the local environment. There particularly remains such a need for a development for volume house-building where the developments comprise more than one structure.

Means for solving the problem [0010] The inventors have devised novel and inventive foundation systems, and method of constructing foundation systems. A broad description will be given of specific aspects of the invention. According to the present invention, there is provided a foundation system as set out in claim 1 and a method of constructing a foundation system as set out in claim 12. Preferred aspects of the invention can be found in the dependent claims.

[0011] According to a preferred aspect of the present invention, a foundation system comprises a swale having a base, a plurality of permeable structures on the base of the swale separating the swale into a plurality of plots, and at least one buoyant foundation positioned on the base of the swale within a permeable structure. According to a preferred aspect of the present invention, a method of constructing a foundation system in a swale, wherein the swale has a base, comprises positioning a plurality of permeable structures on the base of the swale to separate the swale into a plurality of plots, and positioning a buoyant foundation on the base of the swale and inside one of the permeable structures.

[0012] A conventional dug foundation in the base of a swale would be compromised during a flood event. Advantageously, the buoyant foundation being placed on base of a swale allows it rise and fall with the fluid level in the swale and the environmental impact of the foundation system is minimised as there is no need for deep foundations to be dug. In addition, during and after a flood event, water within the swale is not trapped in a pit as may be the case with a deep foundation. Drainage of water during and after a flood event is therefore only minimally affected by the foundation system. Safety is improved by placing the foundation within the permeable structure as the foundation will be protected from debris in the fluid. Further, as the foundation is placed on the base of the swale, the efficiency of construction is also therefore increased as deep foundations are not required.

[0013] In some aspects, a permeable structure comprises a wire mesh container filled with aggregate. In some aspects, a permeable structure comprises a plurality of separated concrete blocks. In some aspects, a permeable structure comprises two parallel porous sheets with aggregate therebetween.

[0014] In some aspects, the buoyant foundation is positioned directly on the base of the swale. These aspects improve the efficiency of construction.

[0015] In some aspects, a permeable structure comprises a reinforcement structure placed on a base of the swale, and wherein the buoyant foundation is placed on the reinforcement structure. These aspects assist in reinforcing the base of the swale.

[0016] A foundation system of any preceding claim, wherein the swale has a raised ground portion extending therethrough. Preferably, multiple plots are each adjacent to the raised ground portion. Preferably, the permeable structure comprises two side walls abutting the raised ground portion and one back wall abutting the two side walls. A raised ground portion will not be submerged as quickly as the base of the swale, if at all. Accordingly, a raised ground portion can provide access to structures on the foundations during a flood event. Further, utilities such as water, electricity, sewerage and communications, can run within the raised ground portion and then be connected to structures associated with the buoyant foundations. Accordingly, the utilities are less vulnerable.

[0017] In some aspects, at least two guide piles associated with at least one of the multiple plots, the at least two guide piles being partially immersed in, and extending vertically from, the base of the swale, and corresponding guides moveably attached to the guide piles, the guides being vertically moveable along the guide piles. Providing two or more guide piles and guides prevents the foundation from rotating about a point during a flood event, thereby reducing the chance of collision with another foundation. As the guides are vertically moveable along the guide piles, there is no restriction on the foundation rising along the guide pile during a flood event.

[0018] In some aspects, a foundation comprises a plurality of cells. If some cells are compromised, the buoyant foundation can still stay afloat. Safety of any structures on the foundation is therefore increased.

[0019] A method of constructing a foundation system according to claim 16, wherein creating a swale comprises excavating spoil and creating a raised ground portion comprises using at least a portion of the excavated spoil. The environmental impact to other sites is minimised as the spoil can be re-used on the site including the building foundation system. Further, efficiency of construction is improved as the raised ground portion can be constructed using materials on-site instead of awaiting materials from another location.

[0020] Various embodiments and aspects of the present invention are described without limitation below, with reference to the accompanying figures.

Brief description of the drawings [0021] Figure 1A shows a side view of a foundation system with a buoyant foundation in a rest position. Figure IB shows a side view of a foundation system with a buoyant foundation in a floating position.

[0022] Figure 2 shows a plan view of groundworks.

[0023] Figure 3A shows a side view of groundworks according to some aspects of the invention. Figure 3B shows a side view of groundworks according to other aspects of the invention.

[0024] Figure 4 shows a side view of groundworks according to some aspects of the invention.

[0025] Figure 5 shows a perspective view of a permeable structure according to some aspects of the invention.

[0026] Figure 6A shows a side view of a foundation system and associated architecture in a rest position. Figure 6B shows a side view of a foundation system and associated architecture in a floating position.

[0027] Figure 7 shows a plan view of groundworks and associated rafts according to some aspects of the invention.

[0028] Figures 8A to 8C show side view of architectures and associated buoyant foundations according to aspects of the invention.

[0029] Figures 9A and 9B show flow charts of constructing a foundation system and associated architectures.

[0030] Figures 10A to 10G show foundation systems and associated architecture at various stages of construction.

Detailed description of a preferred embodiment [0031] A building foundation system 100 for avoiding flood damage to people and buildings, or structures, and their contents is described, along with a method of creating the foundation system 100. As used herein, a foundation system comprises groundworks and one or more foundations. The groundworks 100 comprise a swale 102 divided into multiple plots 108 by a plurality of permeable structures 104.

[0032] The permeable structures 104 preferably comprise a plurality of permeable walls connected together. The plots 108 have a sufficient footprint to accommodate at least the foundation 202 of an architecture 200 that can rise and fall with the water level within the swale 102. Advantageously, the permeable structure 104 of a plot 108 allows fluid to pass through, but prevent debris carried by the fluid from passing. In this way, the permeable structures 104 protect the foundation 202 associated with the plot 108. Further, the groundworks 100 do not require deep foundations to be dug, and the buoyant foundation 202 can be placed above the bottom of the swale 102, for example directly on the base 110 or on a reinforcing structure. The environmental impact of the building foundation system and any associated structure is therefore minimised, while allowing any associated structures to rise with a fluid level in a flood event.

[0033] Foundation System [0034] Fig. 1A shows a foundation system 100 in a first, resting, position (as would be the case when there is no flood event). The foundation system 100 comprises goundworks and a buoyant foundation 202. In terms of a conventional building, a foundation system 100 can be considered as the below-DPM (damp proof membrane) or below-DPC (damp proof course) elements. The buoyant foundation is a load bearing element that is able to float in fluid.

[0035] The groundworks in Fig. 1A comprises a permeable structure, that includes permeable walls 104 and a reinforcing structure 106, positioned in a swale 102 and proximate a raised ground portion 112. The permeable walls 104 are positioned above (or on) the bottom of the swale 102. The foundation 202 is also positioned above the bottom, or base, of the swale 102, and is placed on the reinforcing structure 106. In arrangements where the reinforcing structure 106 is not provided, the foundation 202 is positioned on the base 110 of the swale 102 (i.e. on the bottom of the swale 102). Fig. IB depicts the foundation system 100 as shown in Fig. 1A in a raised configuration as may occur during a flood event. The buoyant foundation 202 is displaced vertically by water in the swale 102.

[0036] Groundworks [0037] Fig. 2 shows a plan view of groundworks according to a preferred embodiment. A swale 102 is excavated or created in any conventional manner and divided into multiple plots 108n-l, 108, 108n+l by a plurality of permeable structures 104 n-1, 104, 104n+l. The swale 102 is a depressed area of ground manufactured to attract and store flood water, similarly to a detention basin. During a flood event water can be directed using the swale 102, which can therefore be used in a similar manner to a diversion canal. Preferably, at least a portion of the spoil from creating the swale 102 is used to create a raised ground portion 112. Conventionally, a swale is sacrificial land and would not be considered for development. With the present foundation system, structures, such as residential or commercial buildings, can be safely built in the swale 102. Fig. 3 A shows a view through line A-A of Fig. 2. Fig. 3B shows a corresponding view in an arrangement without the reinforcement structure 106. The raised ground portion 112 may have a gradient to assist rain water running into the swale 102.

[0038] The width of the swale 102 must be at least sufficient to accommodate a buoyant foundation 202. In the arrangement shown in Figs. 1A and IB, the swale 102 extends further from the raised ground 112 than the permeable structure 104.

[0039] In some arrangements, the width of the swale 102 may also be divided into a plurality of plots 108 (i.e. the plots are in a MxN configuration where M is a number greater than 1 and N is a number greater than 1, wherein M and N can be the same or different).

[0040] The swale 102 is divided into plots 108 by the permeable structure 104. In the arrangement shown in Fig. 2, the swale 102 is divided, along a direction parallel to the raised ground 112, by permeable side-walls 104a of consecutive permeable structures 104n-l, 104n, 104n+l (i.e. the plots 108 are in a lxN configuration where N is a number greater than 1). In a direction perpendicular to the raised ground portion 112, a plot is defined by the back-wall 104b of the permeable structure 104 and the front of the permeable structure closest to the raised ground portion 112. In some aspects, the plot is defined in the direction perpendicular to the raised ground portion 112 by the back-wall of the permeable structure 104 and the raised ground portion 112. The permeable structures 104n-l, 104n, 104n+l therefore define respective plots 108n-l, 108, 108n+l. In other arrangements, the permeable structures 104 are not placed on the outer edge of the plot 108 and, as such, a plot may extend beyond the boundary of the permeable structure 104.

[0041] In some arrangements, the width of the swale 102 may also be divided into a plurality of plots 108 (i.e. the plots are in a MxN configuration where M is a number greater than 1 and N is a number greater than 1, wherein M and N can be the same or different). For example, a plot 108 may be located proximate to the back wall 104b associated with a plot 108 that is next to the raised ground portion 112. A foundation associated with one plot can be connected to the raised ground portion via the foundation associated with another plot.

[0042] The permeable structure 104 is of sufficient dimensions, when viewed from above, that the foundation 202 associated with the plot 108 can fit within the permeable structure 104. The permeable walls 104a, 104b and the reinforcement structure 106 of the permeable structure 104 are discussed in more detail below. Advantageously, during a flood event, the permeable structure 104 allows water to pass through while stopping debris carried by the water. The foundations 202, and the structures 206 built thereon, are therefore protected from the debris during a flood event. Further, the permeable structures 104 will reduce the energy of flood water incident on the foundations 202. At the same time, slowing the flow of flood water prevents the architectures 200 from changing height too quickly thereby improving the comfort and safety for occupants of the buildings 206 of the architectures 200 during a flood event. Further advantageously, the side permeable walls 104a of the permeable structurel04, extending from the back wall 104b, brace the side walls 114 of the raised ground portion 112.

[0043] Fig. 4 is a view through line B-B of Fig. 2, and shows how the side walls 104a of the permeable structure 104 support a side wall of the raised ground portion 112. In other aspects, the permeable walls 104 extend across a portion of the distance between the raised ground portion 112 and the back wall of the permeable structure 104, thereby allowing water to flow more freely between plots 108 while still restricting the flow of debris.

[0044] In addition to controlling the flow of fluid through the plots 108, the permeable structures 104 act as a guide to reduce or prevent lateral, or horizontal, movement (i.e. along or away-from/toward the raised ground portion 112) of the architectures 200 in a flood event. Damage to buildings 206 of the architectures 200 during a flood event can therefore be reduced.

[0045] Permeable Structure [0046] In a preferred embodiment, as shown in Fig. 5, the permeable walls structures 104 are wire mesh containers filled with aggregate (for example, railway ballast, rubble, hardcore or stones), such as gabions. The permeable walls 104a, 104b may comprise one or more such wire mesh container filled with aggregate. This allows fast installation of the permeable structure 104, thereby improving the efficiency of deploying the described system, while providing a structure that limits the size of pieces of debris that can be incident on the foundation 202 in a flood event. Additionally, is it relatively fast to install the wire mesh arrangement, thereby improving the efficiency of deploying the foundation system 100.

[0047] Preferably, the wire mesh containers forming the permeable walls 104a, 104b can be interlocked. In some aspects, the shape of the wire mesh containers can be such that they interlock based on their geometry. For example, one side of a wire mesh container contain a protrusion or other extension away from the interior of the wire mesh container whereas the opposed side contains an indent toward the interior of the wire mesh container. When two such containers abut one another, a protrusion from a first wire mesh container mates with an indent on the second wire mesh container. In another example, wire mesh containers can be interlocked with multiple reinforcing bar (also termed, ‘rebar’). The rebars extend through multiple wire mesh containers of a permeable wall 104. Aggregate in the wire mesh containers will hold the rebars in place, while the rebars limits movement of the wire mesh containers with respect to each other (i.e. where a rebar extends through a first and a second wire mesh container, the movement of the first and second wire mesh containers relative to one another is limited). A particular example of an interlocking gabion appropriate for use with the described foundation system is Ramwall ® (for example, http://www.isseng.com/products/ramwall, and Patent No. GB2419368B) [0048] In other embodiments, the permeable walls 104a, 104b are made of concrete blocks with gaps to allow water to pass. The size of the gaps can be chosen to control the flow of water through a concrete block. If more than one concrete block is used to create a single wall, the gap may be provided between the blocks. In some embodiments, a wall 104a, 104b of the permeable structure 104 will restrict the flow of water along the swale 102 through that wall, preferably to a degree that allows 30% of water contacting one side to pass through as it reaches a permeable wall of the permeable structure 104, while 70% of the water is retained and passes through the wall 104 more slowly. The permeable structure 104 is therefore able to protect the foundation 202 from surging water that may occur during a flood event. In some [0049] [0050] [0051] [0052] arrangements, the permeable walls structures 104a, 104b may comprise a plurality of pylons spaced such that gaps between the pylons allow fluid to pass.

One or more felt layers can be added to the permeable walls 104a, 104b to assist filtering the fluid. Preferably, a felt layer is closer to the inside of a plot 108 (i.e. closer to the foundation 202) than at least some aggregate. The aggregate therefore filters the larger debris from the fluid and reduces the energy of the fluid, thereby protecting the felt which can then filter smaller particulates from the fluid.

In some arrangements, the permeable structure 104 comprises a reinforcement structure 106. A reinforcement structure 106 reinforces the base 110 of the swale 102 on which a foundation 202 will rest, and so may be termed a swale base reinforcement structure. In some aspects, the reinforcement structure 106 can also reinforce the walls of the permeable structure 104 to reduce the risk that those walls will topple into the plot 108.

The reinforcement structure 106 is preferably constructed of at least one wire mesh container (e.g. a basket) filled with aggregate (such as rubble or stones). In some embodiments, the reinforcement structure 106 comprises a plurality of wire mesh containers filled with aggregate. In Fig. 5, the reinforcement structure 106 comprises reinforcement strips (gabion strips) 106a-g located above (or on) the base 110 of the swale 102 inside the permeable walls 104a, 104b, thereby leaving part of the base of the swale 102 exposed. This can assist with water draining into the soil. Each reinforcing strip of the reinforcement structure 106 may comprise a single wire mesh container filled with aggregate. Alternatively, each reinforcing strip may comprise a plurality of mesh containers filled with aggregate. Other arrangements of reinforcing strips 106a-g are possible. For example, the gabion strips 106a-g can extend perpendicular to the back wall, and/or the reinforcement structure 106 can comprise different numbers of gabion strips 106a-g.

In some arrangements, the height of the wire mesh arrangement is less than the length and width, thereby creating a matt or mattress to cover all or substantially all of the base, or bottom, of the swale 102. Particularly, the matt or mattress arrangement can cover, or substantially cover, the base of the swale. An example of such a matt or mattress arrangement is a Reno Mattress® (https://www.maccaferri.com/uk/products/reno-mattresses/reno-mattress/).

[0053] Buoyant Foundation [0054] In a preferred embodiment, the foundation 202 is buoyant such that it rises and falls with the fluid level within an associated plot 108 of the swale 102. Fig. 1A shows a preferred arrangement in a resting configuration, held above the base or bottom of the swale 102 by a reinforcement structure 106. Fig. IB depicts the system shown in Fig. 1A in a raised configuration as may occur during a flood event. As used herein, a foundation 202 is considered buoyant when the foundation 202, and any associated structures 206 built thereon, to remain afloat in fluid that enters the swale 102. For example, that fluid will be water containing silt and debris during a flood event. It will be appreciated that the foundation 202 can rest directly on the base of the swale 102 when a reinforcing structure 106 is not provided. In such an arrangement, the foundation 202 is directly on the base of the swale 102. Due to the weight of the foundation 202 and associated architecture 200, the foundation 202 (or reinforcement structure 106 if present) may depress into the base 110 of the swale 102. However, the present invention with the foundation 202 above (or on) the base 110 of the swale 102, there is no need to dig deep foundations.

[0055] The buoyant foundation 202 is constructed out of one or more hollow containers (either hulls, boxes or cylindrical tubes), with concrete boxes being preferred. In other arrangements, ferro-cement, plastic or steel may be used to construct the foundation 202.

[0056] The one or more boxes or cells may be partitioned into plurality of internal sections or cells 210214. In this way, if some cells 210 214 of the foundation 202 are compromised, the foundation 202 may remain buoyant. The size of the foundation 202 can be varied depending on the expected weight to be placed thereon (for example, the combined weight of any buildings 208, and the contents of those buildings 208, and a raft 204 if present). It will be appreciated that redundancy in the buoyancy of the foundation 202 can be built into the foundation by increasing the volume of the box/cell or boxes/cells.

[0057] A foundation 202 can either be enclosed or open. A foundation 202 is enclosed when all or a substantial part of the top of the foundation box is covered (for example, a hatch to access the interior of the foundation 202 can be present in an enclosed foundation). A foundation 202 is open, or open-topped, when the box comprises a base and side walls, but the top is not covered. An open-topped foundation 202 may have a lip around the top edge of the side walls for safety. Similarly, an open-topped foundation 202 may have a net or mesh covering. With an enclosed foundation, fluid will be prevented or restricted from entering the foundation 202, thereby ensuring the buoyancy of the foundation is not altered in severe weather. An open foundation 202 will be lighter for the same footprint, and will be faster to manufacture.

[0058] In some instances, access into the foundation 202 may be provided from the raft 204. This can allow use of at least part of the inside of the foundation 202 (for example, part of the inside of the foundation 202 may be used similarly to a basement or cellar), and allows for ease of access for maintenance.

[0059] Architecture [0060] An architecture 200 is constructed on the foundation 202, and comprises at least one structure 206. The structure 206 shown on the raft 204 is representative, and the skilled person would understand that any structure 206 or structures 206 can be positioned on the raft 204 as long as the foundation 202 is able to rise with the fluid level in the swale 102 (i.e. the mass of structure 206 is less the mass of volume of water it displaces when afloat). For example, a house and a separate garage can be built on the same foundation 202 or, a commercial building such as a cafe can be built on a foundation 202. In other examples, a car park may be constructed on a foundation 202. In terms of a conventional building, architecture 200 can be considered as the above-DPM (damp proof membrane) or above-DPC (damp proof course) elements.

[0061] Figs. 6A and 6B show arrangements corresponding to Figs. 1A and IB, respectively, when an architecture 200 is constructed on the foundation 202. As shown in Figs. 6A and 6B, the architecture 200 further comprises a floor finish (or ‘raft’) 204 in some arrangements. The raft 204 can be built on top of the foundation 202, and the structure 206 or structures 206 can be built on top of the raft 204. Alternatively, the structure 206 can be built on the base of the foundation 202, and the floor finish 204 can cover the top of the foundation 202 from the edge of the foundation 202 to the structure 206.

[0062] The architecture of Figs. 6A and 6B also includes a bridge 212 extending from the architecture 200 to the raised ground portion 112. As fluid fills the swale 102, the foundation 202, and hence the architecture 200 thereon, rises. The movement of the architecture 200 with fluid level in the swale 102 therefore changes the vertical position of the structure 206 relative to the land (i.e. either on the base 110 of the swale 102 or on top of the raised ground portion 112). To allow access from the top of the raised ground portion 112 to any structure 206 of the architecture 200, the raft 204 is connected to land by a bridge 212 as shown in Figs. 6A and 6B. The bridge 212 may alternately attach to an extended platform of the structure 206. In some arrangements, the bridge 212 is attached to the foundation 202. The bridge adjusts to the height of the raft 204.

[0063] In Figs. 6A and 6B, the bridge 212 is pivotally attached to the architecture 200 at one end, and rests on land on the raised ground portion 112 at the other end. The bridge 212 is therefore in contact with the land, but is not attached thereto. As the foundation 202 rises, the end of the bridge 212 in contact with the landslides toward the foundation 202 while remaining in contact with the land. While the angle of the bridge 212 therefore increases changes as the foundation 202 rises, there remains a connection over which occupants of structures 206 (and vehicles) on the foundation 202 may reach land, and over which people and vehicles on the land may reach the buildings 206. This can be vital if emergency services are required to attend a casualty in a building 206 on the foundation 202. In a less severe scenario, access to the building 206 from the land could be vital to continuation of a small business that occupies that building 206.

[0064] Figs. 8A-C show an architecture 200 and associated foundation 202. The architecture 200 of Fig. 8 A includes a raft 204 and a structure 206. In some arrangements, for example those shown in Figs. 6B and 6C, the raft 204 is omitted. Such arrangements function as described for arrangements including a raft 204, except the building 206 is built directly on the foundation 202 as shown in Figs. 6B and 6C. An arrangement including the raft 204 allows the area on which buildings 206 can be placed to extend beyond the boundaries of the permeable structure 104 when viewed from above (see, for example, raft 204n-l of Fig. 7).

[0065] Raft [0066] The raft 204 is a planar surface above the buoyant foundation 202. In a resting position, as shown in Fig. 6A for example, the raft 204 can be considered to be at ‘ground level’ for a structure 206 associated with a foundation 202. The structure 206 may also include a basement that extends into the foundation 202 beneath the level of the raft 204. The raft 204 may be separate and attached to, or placed on, the foundation 202. In some embodiments, more than one building 206 is built on the raft 204 (for example, in a residential area, a house and a garage may be separate buildings 206 on the same raft 204). A raft 204 can improve the strength of the foundation 202, thereby improving the safety of the architecture 200.

[0067] Fig. 7 shows a plan view of groundworks as shown in Fig. 2, with rafts 204n-l, 204n, 204n+l of architectures 200 overlaid. As can be seen from Fig. 7, different raft 204n1, 204n, 204n+l dimensions are possible. For example, when viewed from above the raft 204n+l may be wholly within the area defined by the permeable structure 104. Put another way, the external dimensions of the raft 204n+l are less that the internal dimensions of the permeable structure 104. In another example, when viewed from above, the raft 204n is larger than the internal dimensions of the permeable structure 104, but smaller than the external dimensions of the permeable structure 104. The raft 204n can therefore partially cover the permeable walls 104a, 104b when viewed from above. In yet another example, when viewed from above, the raft 204n-l is larger than the external dimensions of the permeable structure 104 in at least one direction. The raft 204n-l can be cantilevered over the back wall 104b of the permeable structure 104 or can span two or more plots 108 and the associated permeable structures 104. A larger raft size allows more space to erect buildings. It will be appreciated that the different rafts 204n-l, 204n, 204n+l in Fig. 7 are illustrative and that any combination of raft 204n-l, 204n, 204n+l dimensions is possible. In a preferred embodiment, all rafts 204n-l, 204n, 204n+l are of the same dimensions.

[0068] Guides and Guide Piles [0069] In some aspects, such as shown in Fig. 7, guide piles 116 are driven into the base 110 of the swale 102. The guide piles 116 are partially immersed in the base 110 of the swale 102 and extend vertically away from the base 110 of the swale 102. The arrangement in Fig. 7 shows guide piles 116a, 116c that are driven into the base of the swale 102 within the interior of the permeable structure 104, and guide piles 116b driven into base 110 of the swale 102 next to the permeable structure 104. The guide piles 116a, 116b that are under the raft 204 extend vertically from the base 110 of the swale 102 and through guide apertures 208 on the raft 204 of the architecture 200. The guide piles 116c that are not under the raft 204 extend vertically from the base 110 of the swale 102 and through guide brackets 210 attached to the foundation 202 or to the raft 204. The guide apertures 208 and guide brackets 210 can collectively be termed guides 208, 210.

[0070] As the architecture 200 raises and lowers with fluid in the swale 102, lateral movement is limited to the distance between an edge of a guide 208, 210 and the corresponding guide pile 116. The guide piles 116a can also extend through the foundation 202 in some arrangements. Any combination of guide piles 116a, 116c driven into the base of the swale 102 inside the permeable structure 104 and guide piles 116b driven into base 110 of the swale 102 outside of the footprint of the permeable structure 104 can be implemented. More piles 116 reduces the risk of collision between adjacent architectures 200 caused by failure of a pile 116, but increases cost and friction that must be overcome for the architecture 200 to rise with the fluid level in the swale 102. Some aspects only use the guide brackets 210 attached to the foundation 202 to reduce the risk of damage to the raft 204 and thereby improve safety for occupants of the architecture 200.

[0071] In aspect that incorporates guide piles 116, it is preferred that at least two piles 116 are provided. This prevents rotation of the architecture 200 around a single guide pile 116; therefore improving lateral stability and reducing the chance of damage to the architecture 200 during a flood event.

[0072] Method of Construction [0073] A preferred method of creating a foundation system 100 and associated architecture 200 is set out below. It will be apparent that creating the architecture 200 can be independent of creating the foundation system 100. For example, the foundation system 100 may be created initially and the architecture 200 created at a different time. The preferred method is particularly suited to areas at high risk of flooding, such as flood plains. The method can also be used in other areas where the risk of flooding is lower.

[0074] At step SI, the building area is prepared by cutting a swale area and constructing at least one raised ground portion through the swale area. The raised ground portion at least comprises an elongate strip, the top of which being higher than the surrounding swale area. The top of the raised ground portion is above an expected water level during a flood event. The height of the raised ground portion can be determined by reviewing historical records, for example. In some arrangements, such as that shown in Fig. 10A, the raised ground portion has a road build thereon to connect to the building area. Utilities, such as water, electricity, and communications lines, can be run within the raised ground portion or on the raised ground portion as with a conventional road. The arrangement shown in Fig. 10A includes pipes for utilities with outlets that will be associated with a plot. As also shown in Fig. 10A, some arrangements include tunnels across the width of the elongate portion to the other to allow water to flow from one side of the elongate portion to the other.

[0075] Advantageously, the roads are raised above an expected water level during a flood event, thereby guaranteeing continuous ingress and egress of emergency service vehicles and allowing businesses in the area to stay open. Additionally, as utilities are also within or on the raised ground portion, there is a reduced risk of disruption. In one example, telephone lines may be attached to telephone poles on the raised ground portion. As the telephone poles are above the water level during a flood event, they cannot be pushed over by the flow of water.

[0076] In some arrangements, the ground of the swale 102 is sloped toward the raised ground portion 112. During a flood event, water is therefore attracted to the raised ground portion 112 and, therefore, the plots 108 in which buoyant foundations 202 for architectures 200 will sit. The risk of flood damage to buildings in areas surrounding the swale is thereby reduced, whereas the present arrangement protects the foundations 202 associated with the plots 108 while preventing flooding of the structures 206.

[0077] At step S2, trenches are cut in the base 110 of the swale 112 to accommodate permeable structures 104 for each plot. The trenches are used to locate the permeable structure(s) 104 within the plot 108. As such, the trenches are not required to be deep (i.e. shallow trenches may be used). During a flood event, the trenches assist in preventing lateral movement of the permeable walls 104. In the arrangement shown in Fig. 10B, trenches are cut for each permeable wall 104a, 104b and the reinforcement structure 106. In some aspects, the trenches are not required and so this step is omitted. When the trenches are omitted, other means to locate the permeable structure(s) 104 may be used to ensure the permeable structure(s) 104 will be correctly positioned within the swale 102. For example, temporary markings one the bottom of the swale may replace the trench for the purposes of locating the permeable structures.

[0078] It is preferable to provide a trench for each wall 104a, 104b and reinforcing strip 106a-g of the permeable structure 104. One such arrangement is shown in Fig. 10b. However, in some aspects, trenches are cut for some walls 104a, 104b and/or reinforcing strips 106a-g of the permeable structure 104 but not others. For example, a trench may be cut for the back wall 104b of the permeable structure 104 (i.e. the wall furthest from the raised ground portion) but not the other walls. In another example, trenches may be cut for the walls 104a, 104b of the permeable structure 104, but not the reinforcing strips 106.

[0079] At step S3, the permeable structures 104 are positioned using the locating means. In Fig. 10C, once the permeable structures 104 are positioned, the walls 104a, 104b of the permeable structure 104 delineate one plot 108 from another. The permeable structures 104 can be created in situ by, for example, placing wire mesh containers in the trenches and filling those trenches with aggregate. Alternatively, a gabion may be created offsite, brought to the site and positioned. In some arrangements, each wall 104a, 104b of the permeable structure 104 can be created separately, and interlocked when located at the plot 108. The reinforcement structure 106 can be positioned at the same time, or at a separate time, to the permeable walls 104a, 104b. In arrangements [0080] [0081] [0082] [0083] in which the permeable structure 104 is created from wire mesh containers filled with aggregate, the wire mesh may be situated at the plot by the locating means, and then filled with aggregate.

At step S4, buoyant foundations 202 are positioned inside the permeable structures 104 and above (or on) the base 110 of the swale 102. In the preferred arrangement, the foundations 202 are positioned on the reinforcement structure 106 of the permeable structure 104. In other arrangements, the foundation 202 is positioned directly on the base 110 of the swale 102.

A buoyant foundation may comprise one or more cells 214. In some aspects, when more than one cell 214 is present, each cell 214 may be separate from each other. In such aspects, the combination of a plurality of cells 214 forms the buoyant foundation 202, thereby allowing the foundation to be tailored to an expected load. Fig. 10D shows an aspect in which the buoyant foundation 202 is created from a plurality of individual cells 214. The cells 214 are shown as being open-topped, but can be enclosed volumes.

At step S5, guide piles 116 associated with a plot are driven into the ground. Preferably, the guide piles 116 are driven into the ground inside a plot. In the arrangement shown in Fig. 10E, two guide piles are driven in to the ground inside each plot. In some arrangements, such as that shown in exemplary plot 108n-l of Fig. 7, guide piles 116 can be located outside the plot, although it will be apparent that such guide piles are still associated with the plot 108n-l. Guides 208, 210 are fixedly attached to the buoyant foundation 202 and mate with the guide piles 116 such that the guides are able to move in a vertical direction relative to the guide piles but are restrained in horizontal directions. In the arrangements shown in Figs. 7, 10E and 10F, the guide piles 116 are a male connection and the guide apertures 208 are the female connection.

At step S6, one or more buildings 206 are constructed on the buoyant foundation. In the arrangement shown in Figs. 6A and 6B, for example, a raft 204 is first positioned on the buoyant foundation 202 and the one or more buildings 206 are constructed on the raft 204. In the arrangement shown in Fig. 10F, the one or more buildings 206 are constructed directly on the buoyant foundation 202 (i.e. the building is in physical contact with the buoyant foundation), and the raft 204 is to be added later to cover the remaining gap between the building and the foundation 202 walls.

[0084] At step S7, the buildings 206 can be connected to utilities. For example, sewerage and water pipes can be located in the raised ground portion and can be connected to each building. For example, a water connection tube may be flexible and extend from a water pipe in the raised ground portion to water pipes in the building. Sewerage pipes in the raised ground portion can connect to sewerage pipes in the building via a similar flexible tube. Communication lines and electrical wires can be connected from overhead cables on the raised ground portion. A floor can be added to the top of the foundation in some arrangements. The floor may be termed an external floor as it is external to a structure. In arrangements where the foundation is open-topped, the floor restricts fluid from entering the foundation from the top, as may occur in adverse weather before and during a flood event.

[0085] The architecture 200 will be displaced vertically during a flood event. The guides 208, 210 and guide piled 116 will restrict or prevent horizontal or lateral movement. A flexible connection that compensates for vertical movement is therefore provided between the utilities provided in the raised ground portion 112 and the structure 206. In Fig. 10G, the flexible connection enters through the foundation 202 and is connected at a basement of the building 206. The flexible connection shown in Fig. 10G has some slack to account for the vertical movement of the foundation 202. The slack may be taken up by a spring spool to reduce vulnerability of utility connections.

[0086] In other arrangements, as the horizontal movement of the foundation 202 is restricted, a utility housing can extend vertically upwards from the raised ground portion 112, and is taken across to a point above the foundation 202 where it drops vertically to connections in the basement through a hole in the raft 204. All utilities (e.g. sewerage, water, electricity and communications) may be provided through the utility housing. At a level on which interactions with people and vehicles is likely to occur (i.e. ground level), the utility connections only extend vertically and therefore the vulnerability of the utility connections is minimised. In a similar arrangement, a utility housing can extend downward from the utilities in the raised ground portion enter the foundation vertically upward.

[0087] Other Aspects, Embodiments and Modifications [0088] In some aspects, the swale wall can be strengthened with one or more swale wall reinforcements. Swale wall reinforcements may be concrete blocks or concrete sprayed onto the sidewall of the swale 102. Drainage holes can be provided in the concrete or concrete block to allow water in the soil outside the swale 102 to drain into the swale 102. In other arrangements, the swale wall reinforcements are wire mesh containers filled with aggregate (for example, rubble, hardcore or stones), such as gabions. The swale wall reinforcements may comprise one or more such wire mesh container filled with aggregate, and wire mesh containers of the swale wall reinforcements can be connected in a similar manner to wire mesh containers of the permeable walls 104a, 104b. A particular example of an interlocking gabion appropriate for use with a swale wall reinforcement is Ramwall ® (for example, http://www.iss-eng.com/products/ramwall, and Patent No. GB2419368B).

[0089] The permeable walls 104a, 104b may be constructed of two parallel porous sheets, with aggregate in between. For example, a concrete lattice can be provided as a porous sheet.

[0090] In some aspects, a raft 204 can extend across two or more foundations 202 such that the architecture 200 comprises two or more foundations 202, a raft 204 on the two or more foundations 202 and one or more buildings 206 on the raft 204. The architecture 200 is therefore associated with two plots 108.

[0091] In some aspects, the permeable walls are not intrinsic to particular applications and deployments because the particularities of a given flood location do not require it and/or because of the particular type of buoyant foundation system chosen; for example it may be that if buoyant cylindrical or tubular cells are used rather than boxes, it may be possible to avoid the need for permeable walls around the foundation system because such a system may be able to sustain flow rates and deflect debris self-sufficiently.

[0092] During extreme flood events, the bottom of the buoyant foundation 202 may rise above the top of the associated permeable structure 104. A flexible and vertical skirt or mesh can be provided between the buoyant foundation and the permeable structure to ensure that flood debris is prevented from passing under, and possibly becoming stuck beneath, the buoyant foundation. The flexible and vertical skirt or mesh can be incorporated in arrangements where the anticipated flood level is above the height of the surrounding permeable wall.

[0093] Many other variants and embodiments will be apparent to the skilled reader, all of which are intended to fall within the scope of the invention whether or not covered by the claims as filed. Protection is sought for any and all novel subject matter and combinations thereof disclosed herein.

Claims

Claims (18)

Claims

1. A foundation system comprising:

a swale having a base;

a plurality of permeable structures on the base of the swale separating the swale into a plurality of plots; and at least one buoyant foundation positioned on the base of the swale within a permeable structure.

2. A foundation system of claim 1, wherein at least one permeable structure comprises a wire mesh container filled with aggregate.

3. A foundation system of claim 1, wherein at least one permeable structure comprises a plurality of separated concrete blocks.

4. A foundation system of claim 1, wherein at least one permeable structure comprise two parallel porous sheets with aggregate therebetween.

5. A foundation system of any preceding claim, wherein the buoyant foundation is positioned directly on the base of the swale.

6. A foundation system of any preceding claim, wherein at least one permeable structure comprises a reinforcement structure placed on a base of the swale, and wherein the buoyant foundation is placed on the reinforcement structure.

7. A foundation system of any preceding claim, wherein the swale has a raised ground portion extending therethrough.

8. A foundation system as set out in claim 7, wherein the multiple plots are each adjacent to the raised ground portion.

9. A foundation system as set out in claim 8, wherein the permeable structure comprises two side walls abutting the raised ground portion and one back wall abutting the two side walls.

10. A foundation system of any preceding claim, further comprising:

at least two guide piles associated with at least one of the multiple plots, the at least two guide piles being partially immersed in, and extending vertically from, the base of the swale; and corresponding guides moveably attached to the guide piles, the guides being vertically moveable along the guide piles.

11. A foundation system of any preceding claim, wherein the foundation comprises a plurality of cells.

12. A method of constructing a foundation system in a swale, wherein the swale has a base, the method comprising:

positioning a plurality of permeable structures on the base of the swale to separate the swale into a plurality of plots; and positioning a buoyant foundation on the base of the swale and inside one of the permeable structures.

13. A method of constructing a foundation system according to claim 12, wherein positioning a permeable structure comprises placing at least one wire mesh container abutting the swale and filling the wire mesh container with aggregate.

14. A method of constructing a foundation system according to any of claims 12 to 13, wherein positioning the buoyant foundation comprises positioning the buoyant foundation directly on the base of the swale.

15. A method of constructing a foundation system according to any of claims 12 to 13, further comprising positioning a reinforcing structure on the base of the swale and positioning the buoyant foundation on the reinforcing structure.

16. A method of constructing a foundation system according to any of claims 12 to 15 further comprising creating a raised ground portion extending through the swale.

17. A method of constructing a foundation system according to claim 16, wherein creating a swale comprises excavating spoil and creating a raised ground portion comprises using at least a portion of the excavated spoil.

18. A method of constructing a building foundation system according to any of claims 12 to 17, further comprising driving at least two guide piles vertically into the base of the swale in at least one of the multiple plots;

providing guides associated with the buoyant foundation, wherein the guides are fixed relative to the buoyant foundation and are moveably attached to the guide piles so as to allow vertical movement of the guides along the guide piles.

Intellectual Property Office

Application No: GB1803509.7

Claims searched: 1-18

Examiner: Dr Michael Gooch

Date of search: 7 June 2019

Patents Act 1977: Search Report under Section 17

Documents considered to be relevant:

Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-18 (KABINA) 27/01/2017, Update on KABINA'S NEW FLOODPROOF HOMES FOR THE THAMES VALLEY AND OTHER UK FLOOD ZONES... Kabina, [online]. Available from http://www.kabina.co/newsupdate-jan-2017.php [Accessed 06/06/19] Entire document applicable

Categories:

X Document indicating lack of novelty or inventive step A Document indicating technological background and/or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of before the filing date of this invention. same category. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.

Field of Search:

Search of GB, EP, WO & US patent documents classified in the following areas of the UKCX :

International Classification:

Subclass Subgroup Valid From E02D 0027/04 01/01/2006 B63B 0035/44 01/01/2006 E02D 0027/06 01/01/2006 E04H 0009/14 01/01/2006