In buildings and other large structure, various components (e.g., beams, columns, braces, and/or walls) are connected to each other. The parts of the building and the connections between them are designed so they will not fail catastrophically under the expected loads. The load effects that are transmitted from one part to another include: axial forces, shear forces, and bending moments.
When designing structures to resist severe earthquakes or wind loads, engineers may rely on ductility to prevent catastrophic failure. Engineers may design certain parts of the building to yield in a controlled manner in order to accommodate the large movements associated with severe earthquake or wind loads. The parts of the structure that are typically designed to yield in a controlled manner are beams, braces, walls, and/or columns.
In order to control yielding, engineers may designate a yielding component (such as a brace or beam) and then design all the associate components to be stronger. This approach is called “capacity based” design. Sometimes a yielding component is oversized due to certain requirements, and then “capacity based” design has a cascading effect, resulting in oversizing all associate components. This may lead to structures that are expensive to construct.
After a severe earthquake or wind, the parts of the structure that have been yielded may require repair. Past experience has demonstrated that it is difficult to remove and replace structural components likes beams, braces, walls, and columns. In many cases, it is impractical to repair the buildings. Thus, current deign methods result in buildings that are safe for severe earthquakes and wind (i.e., the buildings will not collapse), but are not resilient (i.e., the buildings may have to be demolished because they are difficult to repair).
Some design procedures determine structural capacity based on the loads that can be carried when a “collapse mechanism” forms. This is known as “plastic design.” Plastic design procedures are only valid when the structural components have certain cross-sectional characteristics that will enable them to yield without experiencing instability. Some structures, particularly those known as “metal buildings” have member cross-sectional characteristics that disqualify them for plastic design.
Embodiments are directed to structural fuses and connection systems including the same. In an embodiment, a structural fuse is disclosed. The structural fuse includes at least one plate and at least one first cutout formed in the at least one plate. The at least one first cutout is configured to form at least one first yield region. The at least one first yield region configured to preferentially yield when a first load is applied to the plate. The structural fuse also includes at least one second cutout formed in the at least one plate. The at least one second cutout is configured to form at least one second yield region. The at least one second yield region is configured to preferentially yield when a second load is applied to the plate. At least a portion of the at least one first yield region is distinct from at least a portion of the at least one second yield region. The first load is different the second load.
In an embodiment, a frame is disclosed. The frame includes a first component, a second component, and a connection system attaching the first component to the second component. The connection system includes at least one structural fuse. The at least one structural fuse includes at least one plate and at least one first cutout formed in the at least one plate. The at least one first cutout is configured to form at least one first yield region. The at least one first yield region configured to preferentially yield when a first load is applied to the plate. The at least one structural fuse also includes at least one second cutout formed in the at least one plate. The at least one second cutout is configured to form at least one second yield region. The at least one second yield region is configured to preferentially yield when a second load is applied to the plate. At least a portion of the at least one first yield region is distinct from at least a portion of the at least one second yield region. The first load is different the second load. The first component and the second component are independently selected from a beam, a column, or a wall plate.
In an embodiment, a frame is disclosed. The frame includes a first component, a second component, and a connection system attaching the first component to the second component. The connection system includes at least one structural fuse. The at least one structural fuse includes at least one plate and at least one first cutout formed in the at least one plate. The at least one first cutout is configured to form at least one first yield region. The at least one first yield region is configured to preferentially yield when a first load is applied to the plate. The first component is a beam and the second component is a beam or a wall plate
Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.
The drawings illustrate several embodiments of the present disclosure, wherein identical reference numerals refer to identical or similar elements or features in different views or embodiments shown in the drawings.
Embodiments are directed to structural fuses and connection systems including the same. An example structural fuse includes at least one plate. The structural fuse includes a plurality of cutouts formed in the plate. The cutouts are configured to cause at least one first yield region of the plate to yield when a first load is applied to the plate. In some embodiments, the plurality of cutouts are configured to cause at least one second yield region to yield when a second load is applied to the plate. At least a portion of the first yield region is distinct from at least a portion of the second yield region and the first load is different than the second load.
The structural fuses disclosed herein are configured to preferentially absorb and dissipate energy from a load by preferentially yielding. As used herein, “yield,” “yielding,” and “yielded” may refer to failing, fracturing, plastically deforming, or otherwise damaging an element (e.g., structural fuse) in a manner that may or may not require the replacement of the element after failure. Examples of loads that may cause yielding of the structural fuses includes loads caused by a seismic event or wind.
The structural fuses disclosed herein may be used in a frame (e.g., a moment-resisting frame, a beam-to-beam connection, a column-to-column connection, a beam-to-column connection, a frame including a collector, an eccentrically braced frame, a steel-plate shear wall building, etc.). The frame may include one or more generally horizontal beams, one or more generally vertical columns, one or more generally obliquely angled braces, a wall plate, or one or more connections that are configured to attach the beams, columns, braces, and/or wall plates together. The frame may form part of or an entirety of a structure (e.g., building). The structural fuses may absorb and dissipate some of the energy of loads applied to the frame which may prevent or avoid yielding of the other elements of the frame (e.g., beam, column, brace, plate wall, connections, etc.) that may otherwise result from the load. As such, the structural fuses disclosed herein may move yielding from the other elements of the frame to the structure fuses to minimize yielding of the other components of the frame. The structural fuses disclosed herein may also be easier to replace after absorbing and dissipating energy from the load than if the other elements of the frame yielded. In other words, the structural fuses may limit the amount of load that may develop in the other elements of the frame thereby preventing damage to such other elements of the frame and making structures that include the frame easier to repair after the load is applied thereto. Further, the structural fuses disclosed herein are proportioned and positioned to yield such that large deformations may occur in the frame to absorb and dissipate energy from the load without losing strength in the structure that includes the frame. As such, the structural fuses disclosed herein may prevent the oversizing of the beams, columns, braces, and wall plates that may occur in a capacity based design and/or can be used to insert a plastic hinge location into the frame that would be otherwise disqualified for plastic design. Thus, the structural fuses may result in more economical design in some structures.
The structural fuse 100 includes at least one cutout 108 formed in the plate 102. The cutout 108 are configured to weaken the plate 102 such that the plate 102 yields in selected regions of the plate 102. For example, the cutout 108 is configured such that the plate 102 yields in one or more yield regions 110. At least a portion (e.g., majority or all) of the yield regions 110 are distinct from at least a portion (e.g., majority or all) of the connection regions 104. As such, failure of plastic deformation of the yield regions 110 of the plate 102 are unlikely to affect the connection between the plate 102 and the other elements of the frame to which the structural fuse 100 is attached. For illustrative purposes, the yield regions are illustrated in
The plate 102 may include a top surface 112 and a bottom surface (not shown) opposite the top surface 112. In an embodiment, the cutout 108 may include an opening formed in the plate 102 that extends from the top surface 112 to the bottom surface. In other words, the cutout 108 may extend completely through the plate 102. When the cutout 108 extends completely through the plate 102, the cutout 108 is distinguishable from the holes 106 that are configured to receive the bolts or rivets by the size of the cutout 108. In an example, the cutout 108 exhibits a maximum lateral dimension or area that is significantly larger (e.g., at least 2 times larger, at least 5 times larger, or at least 10 times larger) than maximum lateral dimension or area the holes 106, respectively. In an example, the cutout 108 exhibits a maximum lateral dimension that is significantly larger (e.g., about 1.5 cm or greater, about 2 cm or greater, about 3 cm or greater, about 4 cm or greater, about 5 cm or greater, about 7.5 cm or greater, or 10 cm or greater) than the maximum lateral dimension of the holes 106. The cutout 108 may be significantly larger than the holes 106 since the cutout 108 is configured to selectively weaken the plate 102 whereas the holes 106 are configured to have a negligible effect on the strength of the plate 102. In an example, the cutout 108 may be distinguishable from the holes 106 because the cutout 108 exhibits a non-circular shape (e.g., elongated or square shape) while the holes 106 are circular. In an embodiment, the cutout 108 may extend from the top surface 112 to an intermediate location between the top surface 112 and the bottom surface. In other words, the cutout 108 may be a selectively thinned region of the plate 102.
The cutout 108 may extend inwardly from an edge 114 of the plate 102 or may be completely surrounded from the plate 102. In an example, the at least one cutout 108 may include a single cutout 108 that is completely surrounded by the plate 102. In an example, the at least one cutout 108 includes a single cutout 108 that extends inwardly from one edge 114 of the plate 102. In an example, the at least one cutout 108 includes a plurality of cutouts 108. In such an example, the plurality of cutouts 108 may extend inwardly from at least one edge 114 of the plate 102, be completely surrounded by the plate 102, or both (e.g., at least one cutout 108 extends inwardly from the edge 114 while at least one other cutout 108 is surrounded by the plate 102).
The cutout 108 may exhibit any suitable shape. Generally, the shape of the cutout 108 exhibits a generally rounded shape (e.g., circular or oblong shape) to prevent stress concentrators, which may cause the structural fuse 100 to fail or plastically deform at unsatisfactory low loads. However, the cutout 108 may exhibit a non-rounded shape, such as a rectangular or square shape. The stress concentrators (e.g., corners) of such non-rounded shapes may allow for more control of which portions of the plate 102 are the yield regions 110. In an example, the cutout 108 may exhibit a longitudinally extending shape, such as an oblong, ellipsoid, or rectangular shape. The longitudinally extending shape may weaken region of the plate 102 that are aligned with the longitudinal axis of the longitudinally extending shape of the cutout 108 thereby allowing for more control of which portions of the plate 102 are the yield region 110. That is, the yield regions 110 are the portions of the plate 102 that are aligned with the longitudinal axis of the cutout 108.
As previously discussed, the at least one cutout 108 may include a plurality of cutouts 108. In an embodiment, at least some of the plurality of cutouts 108 may be arranged on the plate 102 in a generally straight line. Arranging the plurality of cutouts 108 in a generally straight line causes the yield region 110 to be aligned and positioned on the generally straight line. In other words, the yield region 110 is located between the plurality of cutouts 108 arranged in the straight line. As such, arranging the plurality of cutouts 108 in a generally straight line may allow for better control of which portions of the plate 102 that are yield region 110. However, as illustrated in
As previously discussed, the plate 102 includes at least one yield region 110. The yield region 110 includes portions of the plate 102 that are weakened by the cutout 108 such that the yield region 110 preferentially yield when a load is applied to the plate 102. In an example, the at least one cutout 108 includes a plurality of cutouts 108 and the yield region 110 is between adjacent ones of the cutouts 108. In such an example, the yield region 110 is between the adjacent cutouts 108 because the adjacent cutouts 108 weaken a portion of the plate 102 between the cutouts 108. In an example, shown in
The plate 102 may exhibit a major axis 116. The major axis 116 is generally aligned with a longitudinal axis of the beam or column to which the plate 102 is attached. Additionally or alternatively, the major axis 116 of the plate 102 may be the longitudinal axis of the plate when the plate 102 includes a longitudinal axis (e.g., the plate 102 is not square or circular). The yield region 110 may extend from the cutout 108 is an angle that is generally parallel to, generally perpendicular to, or oblique relative to the major axis 116 of the plate 102.
The direction that the yield region 110 extends from the cutout 108 effects which load applied to the structural fuse causes the yield region 110 to yield. For example, only loads that are generally parallel to the direction that the yield region 110 extends from the cutout 108 may cause the yield region 110 to yield. When a load is applied to the structural fuse 100 that is obliquely angled relative to the yield region 110, the obliquely angled load may be broken into a first load component that is generally parallel to the direction that the yield region 110 extends from the cutout 108 and a second load component that is perpendicular to the first load. The first load component may cause the yield region 110 to yield while the second load component is unlikely to cause the yield region 110 to yield.
Referring to
The load L illustrated in
Referring back to
As previously discussed, the structural fuses disclosed herein may exhibit a generally L-shaped cross-section. In other words, the structural fuses disclosed herein may be an angle. For example,
The plate 202 of the structural fuse 200 may be an angle. For example, the plate 202 may include a first section 218 and a second section 220. The first and second planar sections 218, 220 are illustrated as being generally planar though the first and second planar sections 218, 220 may be bent or curved. The first section 218 may be oriented at a perpendicular or oblique (e.g., acute or obtuse) angle relative to the second section 220 such that the plate 202 exhibits a generally L-like cross-sectional shape. In an embodiment, as illustrated, the first and second sections 218 are formed from two distinct plates that are attached (e.g., welded) together. In an embodiment, the plate 202 is formed from a single piece of material that is bent, extruded, or otherwise shaped to form the first and second sections 218, 220.
At least one of the first or second section 218, 220 may include at least one cutout 208 formed therein. For example, as shown in
The structural fuses illustrated in
As such, in some embodiments, the structural fuses disclosed herein may be configured to include at least one first yield region that is configured to yield when a first load is applied to the structural fuse and at least one second yield region that is configured to yield when a second load is applied to the structural fuse. The first load and the second load are different from each other. For example, the first load and the second load may be at least one of different types of loads (e.g., shear and tensile loads), the same type of load applied at different directions to the structural fuse (e.g., parallel and perpendicular to the major axis of the structural fuse), or different components of the same load.
The plurality of cutouts includes at least one first cutout 308a and at least one second cutout 308b and the plurality of yield regions includes at least one first yield region 310a and at least one second yield region 310b. The first cutout 308a is configured to form the first yield region 310a when a first load L1 (shown in
In the illustrated embodiment, the at least one first yield region 310a extends from the first cutout 308a in a first direction. The first direction is illustrated as being generally parallel to the major axis 316 of the plate 302 though the first direction may be oblique or perpendicular to the major axis 316. The first yield region 310a may extend from the first cutout 308a in the first direction because, for example, the first cutout 308a exhibits an elongated shape and the longitudinal axis of the elongated shape extends in the first direction. The direction that the first yield regions 310a extends from the first cutout 308a allows the first yield regions 310a to preferentially yield when the first load L1 is parallel to the first direction. As previously discussed, the first load L1 may be an entirety of a load applied to the structural fuse 300 or may be a component of a load that is generally parallel to the first direction when the load that forms the first load L1 is parallel or obliquely angled, respectively, to the first direction. The first cutout 308a is configured to cause the first yield regions 310a to extend therefrom in a direction that is generally parallel to the first direction by weakening the portions of the plate 302 that forms the first yield region 310a. In an example, as illustrated, the first cutout 308a may weaken a portion of the plate 302 that extends from the first cutout 308a to an edge 314 (e.g., a cross-wise edge) of the plate 302. In such an example, the first cutout 308a is spaced from the edge 314 and there is no additional first cutout 308a extending inwardly from the edge 314. In an example, as illustrated, the first cutout 308a and the second cutout 308a may weaken a portion of the plate 302 that extends from the first cutout 308a to the second cutout 308b in a direction that is generally parallel to the first direction. In an example, not shown, the first cutout 308a may extend inwardly from the edge 314 and/or the first cutout 308a may include a plurality of first cutouts 308a that are arranged in a lines, as previously discussed with regards to the cutouts illustrated in
In an embodiment, the first yield region 308a may include a plurality of first yield regions 310a that are arranged in a line that is generally parallel to the first direction. In an embodiment, the first yield region 310a may include a plurality of first yield regions 310a that form two or more lines that are each generally parallel to the first direction. In such an embodiment, the two or more lines of the first yield regions 310a may facilitate yielding caused by a tensile load than if the plurality of first yield regions 310a were arranged in a single line.
In the illustrated embodiment, the at least one second yield region 310b extends from the second cutout 308b in a second direction that is different than the first direction. The second direction is illustrated as being generally perpendicular to the major axis 316 of the plate 302 through, it is noted, the second direction may be oblique or perpendicular to the major axis 316. The second yield region 310b may extend from the second cutout 308b in the second direction because, for example, the second cutout 308b exhibits an elongated shape and the longitudinal axis of the elongated shape extends in the second direction. The second yield regions 310b extending from the second cutout 308b in the second direction allows the second yield regions 310b to preferentially yield when the second load L2 is parallel to the second direction. As previously discussed, the second load L2 may be an entirety of a load applied to the structural fuse 300 or may be a component of a load that is generally perpendicular to the second direction when the load that forms the second load L2 is perpendicular or obliquely angled, respectively, to the second direction. The second cutout 308b is configured to cause the second yield regions 310b to extend therefrom in a direction that is generally parallel to the second direction by weakening the portions of the plate 302 that forms the second yield region 310b. In an example, as illustrated, the second cutout 308b may weaken a portion of the plate 302 that extends from the second cutout 308b to an edge 314 (e.g., a longitudinal edge) of the plate 302. In such an example, the second cutout 308b is spaced from the edge 314 and there is no additional second cutout 308b extending inwardly from the edge 314. In an example, not shown, the second cutout 308b may extend inwardly from the edge 314 and/or the second cutout 308b may include a plurality of second cutouts 308b that are arranged in lines, as previously discussed with regards to the cutouts illustrated in
Referring to
Unlike the structural fuses illustrated in
The plurality of cutouts includes at least one first cutout 408a and at least one second cutout 408b. The plurality of yield region include a plurality of first yield regions 410a and one or more second yield regions 410b. The first cutout 408a and the second cutout 408b are both configured to form the first yield regions 410a and the second yield regions 410b. The first yield regions 410a are configured to extend from the first and the second cutouts 408a, 408b in a first direction and the second yield regions 410b are configured to extend from the first and second cutouts 408a, 480b in a second direction that is different than the first direction. In an example, as shown, the first and second directions are generally parallel and perpendicular, respectively, to the major axis 416 of the plate 402. As such, the structural fuse 400 may be configured to absorb and dissipate energy in response to two different loads, such as the first load L1 and the second load L2.
The first cutout 408a and the first yield regions 410a extending therefrom are arranged in a first line that is generally parallel to the first direction. The second cutout 408a and the first yield regions 410a extending therefrom are arranged in a second line that is generally parallel to the first direction and offset relative to the first line. As such, the first and second cutouts 408, 408b weaken portions of the plate 402 between adjacent ones of the cutouts and/or cutouts and the edges 414 (e.g., cross-wise edges) of the plate 402. In an embodiment, the first and second cutouts 408a, 408b may exhibit longitudinal shapes and the longitudinal axes of the longitudinal shapes are aligned parallel to the first direction.
The first cutout 408a and the second cutout 408b are arranged on the first and second lines such that a portion of the first cutout 408b overlaps (in the second direction) with a portion of one or more of the second cutout 408b and vice versa. The second yield regions 410b extend between the overlapping portions of the first and second cutouts 408a, 408b. In other words, the first and second cutouts 408a, 408b weaken portions of the plate 402 between the overlapping portions of the first and second cutouts 408a, 408b.
Referring to
In some embodiment, the structural fuses illustrated in
The component 521 is formed from one or more plates. In an example, as illustrated, the component 521 is illustrates as an I-beam and the plates of the component 521 includes two flanges 522 and a web 524 extending between the two flanges 522. The flanges 522 and the web 524 may be attached together (e.g., via welding) or integrally formed (e.g., extruded). In an example, the component 521 may be a hollowed structural section beam, an L-beam, a T-beam, a channel, or any other structure used in frames. In such an example, the flanges, webs, etc. of such components form the plates of the component 521. In an embodiment, as illustrated, the component 521 may be configured to be attached to another component of the frame, such as a plate that attached the component 521 to a beam or column. In such an embodiment, the component 521 may define one or more holes 506 when the component 521 is attached to the other component using bolts.
One or more of the plates of the component 521 (e.g., one or more of the two flanges 522 or the web 524) defines at least one cutout 508. In the illustrated embodiment, the cutout 508 defined by the plate of the component 521 are arranged in the same manner as the cutouts illustrated in
As previously discussed, the structural fuses disclosed herein form part of frames.
The first and second beams 632, 634 are attached together using a beam-to-beam connection system 650. The beam-to-beam connection system 650 includes at least one of a first plate 640 or a second plate 642. The first plate 640 may be attached to adjacent flanges 622a, 624b of the first and second beams 632, 634. The second plate 642 may be attached to adjacent flanges 622a, 624b of the first and second beams 632, 634 that are opposite the flanges 622a, 624b of the first and second beams 632, 634 that are attached to the first plate 640. The first and second plates 640, 642 are illustrated as being attached to the first and second beams 632, 634 using one or more bolts 662. However, the first and second plates 640, 642 may be riveted, welded, or otherwise attached to the first and second beams 632, 634.
At least one of the first or second plate 640, 642 may be any of the structural fuses disclosed herein. For example, at least one of the first or second plate 640, 642 may define at least one cutout that is configured to form one or more yield regions. In an embodiment, both the first and second plates 640, 642 are the structural fuses or only the first plate 640 is the structural fuse. In an embodiment, only the second plate 642 is the structural fuse. In such an embodiment, only the second plate 642 may be the structural fuse when a floor is formed on the frame 630 such that the floor is formed over the first plate 640. The floor may make accessing and repairing the first plate 640 difficult. However, the second plate 642 may be accessed and repaired through the ceiling which may be significantly easier than accessing and repairing the first plate 640 through the floor.
The first and second plates 640, 642 may be attached to the web 624a, 624b of the first and second beams 632, 634 instead of or in addition to the flanges 622a, 622b. For example,
The beam 1032 may be attached to the first flange 1058a of the column 1044 using a beam-to-column connection system 1050. The beam-to-column connection system 1050 includes a first plate 1040 and a second plate 1042 attached to the first flange 1058a of the column 1044. The first and second plates 1040, 1042 may be attached to the first flange 1058 using welding, bolts, rivets, or any other technique. The first plate 1040 is configured to be attached to the top flange 1022a of the beam 1032 using one or more bolts 1062 or any other attachment technique. In the illustrated embodiment, the first plate 1040 is directly attached to the top flange 1022a though, in some embodiments, the first plate 1040 may be indirectly attached to the top flange 1022a, such as via at least one additional plate. The second plate 1040 is configured to be attached, either directly or indirectly, to the bottom flange 1022b of the beam 1032 using any suitable technique. In the illustrated embodiment, when the second plate 1040 is indirectly attached to the bottom flange 1022b, the beam-to-column connection system 1050 includes a third plate 1064 directly attached (e.g., welded, bolted, etc.) to the bottom flange 1022b of the beam 1032. The third plate 1064 may be attached to the second plate 1042 using one or more bolts 1062, welding, or any other attachment technique. The beam 1032 may define a cutout 1066 that is configured to receive the second plate 1042. In some embodiments, the beam-to-column connection system 1050 also includes a shear tab 1068 attached to the first flange 1058a of the column 1044 and the web 1026 of the beam 1032.
One or more of the first plate 1040, the second plate 1042, or the third plate 1064 is a structural fuse (e.g., defines at least one cutout configured to form yield regions). For example, the third plate 1064 may include the structural fuse since the third plate 1064 may be easier to replace that the first or second plates 1040, 1042. The structural fuse may limit bending moments in the beam-to-column connection system 1050 and can prevent yielding of the beam 1032 and the column 1044 when a load (not shown) is applied to the frame 1030. Further, the structural fuse may change the governing limit state for the beam 1032, if necessary, so that plastic design procedures can be used in the frame 1050.
The frame 1130 may include one or more mounts 1172 that are each attached to the plate wall 1170 and one of the beams 1132 or the columns 1144. For example, in the illustrated embodiment, the frame 1130 includes four mounts 1172 and each of the mounts 1172 are attached to one of the beams 1132 or the columns 1144 and the wall plate 1172. Each of the mounts 1172 may include a planar plate and/or an angle (i.e., an L-shaped beam). It is noted that attaching the plate wall 1170 to the beams 1132 and the columns 1144 with the mounts 1172 may decrease the cost of forming the shear plate wall than if the plate wall 1170 was attached to the beams 1132 and the columns 1144 using conventional techniques. At least one of the mounts 1172 is a structural fuse. That is, at least one of the mounts 1172 includes at least one cutout formed therein that form one or more yield regions.
A load applied to a conventional plate shear wall (e.g., a plate shear wall without a structural fuse) may cause the steel plate wall thereof to yield. Repairing the yielded steel plate wall is very difficult. However, a load applied to the frame 1130 may cause one or more of the mounts 1172 to yield instead of the plate wall 1170. Repairing the yielded mounts 1172 may be significantly easier and less expensive than repairing the plate wall 1170.
Further examples of connection systems (e.g., beam-to-beam and beam-to-column connection systems) that may use any of the structural fuses disclosed herein are disclosed in U.S. Provisional Patent Application No. 63/174,663 filed on Apr. 14, 2021, U.S. Pat. No. 10,689,876 filed on Aug. 10, 2018, U.S. Pat. No. 10,584,477 filed on Apr. 25, 2019, U.S. Pat. No. 10,316,507 filed on Aug. 26, 2015, U.S. Pat. No. 10,760,261 filed on Dec. 8, 2016, and International Application No. WO 2021/030111 filed on Aug. 5, 2020, the disclosures of each of which are incorporated herein, in its entirety, by this reference.
While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting.
Terms of degree (e.g., “about,” “substantially,” “generally,” etc.) indicate structurally or functionally insignificant variations. In an example, when the term of degree is included with a term indicating quantity, the term of degree is interpreted to mean±10%, ±5%, or +2% of the term indicating quantity. In an example, when the term of degree is used to modify a shape, the term of degree indicates that the shape being modified by the term of degree has the appearance of the disclosed shape. For instance, the term of degree may be used to indicate that the shape may have rounded corners instead of sharp corners, curved edges instead of straight edges, one or more protrusions extending therefrom, is oblong, is the same as the disclosed shape, etc.
This application claims priority to U.S. Provisional Patent Application No. 63/174,706 filed on Apr. 14, 2021, the disclosure of which is incorporated herein, in its entirety, by this reference.
Number | Date | Country | |
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63174706 | Apr 2021 | US |