KR101798007B1

KR101798007B1 - Frame used in building

Info

Publication number: KR101798007B1
Application number: KR1020150171111A
Authority: KR
Inventors: 주영규; 도병호; 박만우
Original assignee: 동부제철 주식회사; 고려대학교 산학협력단
Priority date: 2015-12-03
Filing date: 2015-12-03
Publication date: 2017-12-12
Also published as: KR20170065100A

Abstract

A frame for a building, comprising: a raft portion for supporting a roof; and a column portion fixed at one end to the raft portion and fixed at the other end to the ground, wherein the raft portion includes a raft web centered on the upper and lower sides A raft web that is vertically coupled to the raft web, and an expandable end that is further extended in both lateral directions of the raft web portion that is vertically coupled to the raft web and the raft flange, A column inner expandable flange coupled to the expandable end plate; And an abutment surface reinforcement plate including a column stiffener vertically coupled to the column inner expandable flange, the abutment surface reinforcement plate having an end disposed in contact with the expandable end plate and a bottom surface coupled to an outer surface of the raft flange, And a center line passing through the center of the column stiffener on the basis of the thickness of the column stiffener passes through the center of the building on the basis of the thickness of the reinforcing portion formed by combining the raft flange and the joint surface reinforcing plate.

Description

Frame for buildings {Frame used in building}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frame for a building, and more particularly, to a frame for a building used in a steel structure such as a factory or a warehouse.

Typical buildings such as houses and buildings are constructed using materials such as reinforced concrete or steel-concrete. However, in the case of buildings such as factories, temporary buildings and warehouses, a frame is formed by a steel frame, and a metallic panel is mounted on a roof and a wall on a frame formed of a steel frame. In the case of such a steel frame structure, not only the process such as concrete casting is greatly reduced but also most of the steel frame frames are mass-produced in a factory and used for construction, which is advantageous in that the air is greatly reduced.

However, in the case of a building constructed only of steel frame, there is a high possibility that local buckling occurs at a portion where loads are concentrated. As a result, it is disadvantageous in comparison with an ordinary reinforced concrete (RC) concrete building due to an uncertain load caused by an earthquake, snow, wind and the like.

In order to prevent this, a reinforcing plate is further disposed on the flange of the building (the raft portion), so that the center lines may be discordant with each other due to the thickness difference with the column stiffener. Then, when the load is applied, unbalanced transmission of force occurs between the beam and the column, and in particular, there is a problem that stress concentrates near the joining surface of the beam and the column.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a frame for a building which is easy to construct and has excellent seismic performance.

Also, the joint between the column and the beam is reinforced to prevent local buckling from occurring at the portion according to the seismic load. Particularly, it aims to reduce the stress concentrated in the vicinity of the joint surface of the beam and the column.

It is also intended to reduce the stress concentrated on the column web. It is also intended to maintain and maintain the internal space utilization of the building, despite the arrangement of the joint face reinforcement plates for stress reduction.

In order to solve the above-mentioned problems, an embodiment of the present invention is a building frame comprising a raft portion for supporting a roof, and a column portion fixed to the raft portion at one end and fixed to the ground at the other end, A pair of upper and lower raft webs, a pair of upper and lower raft webs, and a pair of upper and lower raft webs, An expandable end plate extending further in both lateral and lateral directions of the web portion, the post having a column internal expandable flange engaged with the expandable end plate; And an abutment surface reinforcement plate including a column stiffener vertically coupled to the column inner expandable flange, the abutment surface reinforcement plate having an end disposed in contact with the expandable end plate and a bottom surface coupled to an outer surface of the raft flange, And a center line passing through the center of the column stiffener on the basis of the thickness of the column stiffener passes through the center of the building on the basis of the thickness of the reinforcing portion formed by combining the raft flange and the joint surface reinforcing plate.

Wherein the joint surface reinforcing plate comprises: a rectangular portion extending in the same width as the cage; And a tapered portion extending from the rectangular portion, the width of which is smaller than the width of the rectangular portion and gradually decreasing in width, wherein the tapered portion is smaller than the thickness of the rectangular portion Do.

The rectangular portion may be formed to have the same thickness as the raft flange, and the taper portion may be formed to be 0.5 times the thickness of the raft flange.

Wherein the joint surface reinforcing plate comprises: a rectangular portion extending in the same width as the cage; And a trapezoidal portion extending in the rectangular portion and having a gradually decreasing width.

Wherein the joint surface reinforcement plate is formed of a rectangular portion that extends the same width as the raft flange and the length of the joint surface reinforcement plate is greater than or equal to the width of the raft flange and the height of the raft web portion Or less than 0.4 times of

And a right triangle rib plate vertically coupled to the joint surface reinforcing plate and the expandable end plate, respectively.

Wherein the C-shaped convex portion of the C-shaped convex portion is fixed to the rat fulcrum portion and the pillar portion, and the overall shape of the C- And a column web reinforcement plate arranged to be inclined to the right upper chamber.

Wherein the columnar web located between the column stiffeners has a symmetrical C-shape having a different inner and outer curvature and narrower widths of the convex portions, the convex portions being directed toward the outer side of the ratchet portion and the column portion, And a column web reinforcement plate whose overall shape is arranged and joined to the joining face in an oblique upper right room.

The center of gravity of the column web reinforcement plate may be disposed in the center of a panel zone formed by the column stiffener.

As described above, according to the present invention, various effects including the following can be expected. However, the present invention does not necessarily achieve the following effects.

It is possible to provide a frame for a building which is easy to construct and has excellent seismic performance. Also, it is possible to reinforce the joint surface between the column and the beam, thereby preventing local buckling from occurring at the portion according to the seismic load. In particular, the stress concentrated in the vicinity of the joint surface of the beam and the column can be reduced. Simulation results show that the bonded plate reinforcing plate could dissipate about 20% energy.

Also, the stress concentrated on the column web can be reduced. In addition, despite the arrangement of the joint face reinforcement plate for stress reduction, it is possible to maintain and maintain the internal space utilization of the building.

1 is an exploded perspective view of a building using a frame for a building according to a first embodiment of the present invention;
Fig. 2 is a front view of the building frame of Fig. 1
3 is an enlarged view of A in Fig.
Fig. 4 is a perspective view of Fig. 2,
5 is a perspective view of a bonded surface strengthening plate according to the first embodiment.
Fig. 6 is a table summarizing the stress distribution according to the dimensional change of Fig. 5
FIG. 7 is a graph showing the energy dissipation capacity
FIG. 8 is a perspective view of a bonding face reinforcing plate according to the second embodiment. FIG.
Fig. 9 is a perspective view of the bonded surface reinforcing plate of Fig. 8,
Fig. 10 is a perspective view of the bonding face reinforcing plate according to the third embodiment. Fig.
11 is a perspective view of the bonded surface reinforcing plate of FIG. 10,
12 and 13 are perspective views showing a deformable shape of the column web reinforcing plate,

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

1 is an exploded perspective view of a building using a building frame according to a first embodiment of the present invention.

As shown in FIG. 1, the building using the building frame according to the first embodiment of the present invention includes a first building frame 100 arranged at a plurality of intervals in the longitudinal direction of the building, And a panel 300 fixed to the upper surface of the secondary frame 200. The panel frame 300 includes a first frame 200 and a second frame 200,

As shown in FIG. 1, a building using the building frame according to the first embodiment of the present invention is a building used for a factory, a distribution center, a hangar, etc., and is constructed of a steel frame and a panel 300. The building frame according to the first embodiment of the present invention corresponds to the first building frame 100 shown in Fig. 1, and is hereinafter abbreviated as a building frame.

Fig. 2 is a front view of the building frame of Fig. 1; Referring to FIG. 2, a building frame according to an embodiment of the present invention includes a cradle 110, a column 120, a bonding surface reinforcing plate 200a, and a column web reinforcing plate 300a.

The raft portion 110 includes a raft web 113, a raft flange 111, and an expandable end plate 114 as a portion for supporting the roof. Here, the raft flange 111 is a kind of horizontal plate, and the raft web 113 and the expandable end plate 114 can be regarded as a kind of vertical plate.

The raft web 113 indicates a plate disposed in the middle portion of the raft portion 110. The raft flange 111 is vertically coupled to the upper and lower sides of the raft web 113. Specifically, the raft flange 111 comprises a raft inner flange facing one side of the building and a raft outer flange facing away from the other side of the building toward the outside of the building.

That is, the raft inner flange and the raft outer flange are coupled to each other on the upper and lower sides of the raft web 113 to have a generally H-shaped cross-sectional shape. In addition, the height of the raft web 113 is variably formed in accordance with the stress (typically, a moment diagram) applied to the raft portion 110 formed by the load applied to the structure.

The extended end plate 114 is vertically disposed and connected to the cage 113 and the cage 110 at one end of the cage 110 to form a joint surface with the cage 120, .

More specifically, the expandable end plate 114 is further extended in both lateral directions of the height D of the portion of the raft web 113 coupled to the expandable end plate 114, (114). In addition, a column internal expanding flange 121a corresponding to the expandable end plate 114 is formed on the column 120. As shown in FIG. That is, the area of the joint surface is further increased by the expandable end plate 114 and the column expandable flange 121a than before. Here, the column internal expanding flange 121a indicates a part of the column inner flange 121. [

At this time, the joint surface is firmly joined by the fastening member such as the bolt 115 or the like. To this end, the expansion end plate 114 and the column internal expanding flange 121a are formed at corresponding positions so that a plurality of fastening holes are communicated with each other.

The column 120 includes a column inner flange 121 facing one side of the building and a column outer flange 122 disposed on the opposite side of the column inner flange 121, And a columnar stiffener 124 vertically coupled to the columnar external flange 122 and the column internal expandable flange 121a respectively connecting the columnar internal flange 121 and the columnar external flange 122 .

The column inner flange 121 and the column outer flange 122 are coupled to each other in the upper and lower directions of the columnar web 123 to have a generally H-shaped cross section. The height of the column web 123 is larger at the other end coupled with the cradle 110 than at one end fixed to the ground. That is, in FIG. 2, H2 is formed larger than H1. This is also because it is variably formed in accordance with the stress applied to the column formed by the load applied to the structure.

3 is an enlarged view of A in Fig. 3, the column stiffener 124 is disposed in the vicinity of the extension line of the raft flange 111. As shown in Fig. That is, the pillar stiffener 124 is disposed in the vicinity of each extended line to the inside flange 111 of the rack and the outside flange 112 of the rack. As a result, a panel zone 250 having a predetermined area is formed at the other end of the columnar section 120.

At this time, the pillar stiffener 124 is arranged so that the center line C1 passing through the center in the thickness direction is passed through the center in the thickness direction of the reinforcing portion formed by the coupling of the raft flange 111 and the bonding surface reinforcing plate 200a .

This is because a difference in thickness occurs between the column stiffener 124 and the reinforcing portion in the vicinity of the bonding surface due to the bonding of the bonding surface reinforcing plate 200a, which causes an imbalance in the process of transmitting the force, As shown in FIG.

Here, the thicknesses of the column stiffener 124, the raft flange 111, and the bonding surface reinforcing plate 200a may vary due to design changes and the like. The pillar stiffener 124 and the raft flange 111 have the same thickness, but the joint surface reinforcing plate 200a can be varied based on the thickness of the raft flange 111. [ As a result, the reinforcing portion is formed to be larger than the thickness of the column stiffener 124.

For example, the joint surface strengthening plate 200a may be formed to have the same thickness as the raft flange 111. [ Then, the height of the flange 111 to which the joint surface reinforcing plate 200a is coupled is twice the thickness of the column stiffener 124. Therefore, the center line C1 of the column stiffener 124 is placed on the mating surface of the raft flange 111 and the joint surface reinforcing plate 200a.

In the structure of the embodiment of the present invention, the foundation (the portion where the column portion 120 and the surface are fixed) is pinned (i.e., the horizontal load and the vertical load are fixed to the foundation but the moment load The coupling between the pillar 120 and the cradle 110 is rigid (i.e., not only in the horizontal and vertical directions but also between the pillar 120 and the cradle 110) And also supports a moment load applied therebetween). As a result, when a load reciprocating in the horizontal direction, such as an earthquake, is applied, the largest load is applied to the joint surface, and local buckling or the like also occurs at the joint surface.

In order to reinforce the local buckling that may occur due to an earthquake or the like, the joint surface reinforcement plate 200a and the column web reinforcement plate 300a are further joined to the joint surface. At this time, a welding method capable of maintaining the original shape of the plate inherently by the joining method can be used.

In this way, when an unexpected support load or the like is applied to the structure, the bonding surface reinforcing plate 200a and the column web reinforcing plate 300a not only increase the rigidity of the structure but also cause plastic deformation and the like The frame 100 for the first building not only prevents the main body from being deformed, but also slows down the time required for the destruction, thereby providing time for the personnel residing inside the building to escape.

In detail, the seismic design coefficient Cs of the building is determined by the following equation (1).

S is the acceleration coefficient determined by the area and the ground, I is the importance coefficient determined by the use of the building, R is the reaction correction coefficient, T is the natural period of the building

Here, the reaction correction coefficient is determined by the following equation (2).

Rμ: ductility coefficient, R _Ω : excess strength coefficient, R _ζ : damping coefficient

As the seismic design coefficient decreases, the seismic performance of the building improves. Accordingly, as the response correction coefficient increases, the seismic performance improves. As a result of adding the bonding surface reinforcing plate 200a and the column web reinforcing plate 300a to the above reaction correction coefficient, the excess strength coefficient naturally increases, and even if the initial load due to the earthquake is applied to the building frame, The duct 200a and the column web reinforcing plate 300a are first plastically deformed, and the ductility coefficient and the damping coefficient are also increased, thereby increasing the reaction correction factor as a whole.

These advantages were confirmed by finite element analysis.

The joint surface reinforcing plates 200a, 200b and 200c are arranged such that their ends abut against the expandable end plate and their bottom surfaces are respectively engaged with the outer surface of the cage 111. [ As a result, the bonding surface reinforcing plates 200a, 200b, and 200c can effectively absorb the energy transmitted due to an earthquake or the like, thereby further reinforcing the rigidity of the bonding surface.

FIG. 4 is a perspective view of FIG. 2 viewed from above and FIG. 5 is a perspective view of a bonded surface augmentation plate 200a according to the first embodiment. 4 and 5, the bonding surface reinforcing plate 200a is composed of a rectangular plate portion 210a and a tapered portion 220, and is a combined plate having a predetermined thickness. At this time, the bonding surface reinforcing plate 200a may be formed as a unitary single shape, which is named separately for each part in order to specifically divide the shape.

The rectangular portion 210a extends in the same width as the raft flange 111. The tapered portion 220 has a tapered shape in which the width of the portion extending from the rectangular portion 210a is smaller than the width of the rectangular portion 210a and gradually decreasing in width. Here, the tapered portion 220 is formed to be smaller than the thickness of the rectangular portion 210a.

At this time, the total length of the bonding face reinforcing plate 200a and the length of the other side of the rectangular portion 210a may be changed by design change or the like. However, the total length of the joint surface reinforcing plate 200a does not exceed the height D of the portion of the raft web 113 that is coupled to the expandable end plate 114, and the length of the other side of the rectangular portion 210a, Does not exceed 1.6 times the width (B) of the flange (111). The rectangular portion 210a is formed to have the same thickness as the raft flange 111 and the taper portion 220 is formed to be 0.5 times the thickness of the raft flange 111. [

FIG. 6 is a table summarizing the stress distribution according to the dimensional change of FIG. Referring to FIG. 6, the reference value is a value measured when the bonding face reinforcing plate 200a is not engaged. The specific dimensions of each model are expressed based on the above-mentioned height (D) and width (B). The portion where the stress value is measured is a portion where both ends of the raft flange 111 to which the joint surface reinforcing plate 200a is engaged and the portion where the tapered portion 220 is located and the panel zone 250. The stress values were based on the interlayer displacement angle of 2%.

For example, the second model in Fig. 6 is 0.3D_1.0B_T12,6. Here, 0.3D means that the total length of the bonding face reinforcing plate 200a is 0.3 times the height D and 1.0B means that the length of the other side of the rectangular portion 210a is 1.0 times the width B T12,6 means that the thickness of the rectangular portion 210a is 12 mm and the thickness of the tapered portion 220 is 6 mm. The notation for the other models is interpreted in the same way.

6, the change in the vicinity of the bonding surface at one end of the bonding surface reinforcing plate 200a, in particular, showed the greatest change with the change of the dimensions of the bonding surface reinforcing plate 200a. Specifically, the stress in the vicinity of the bonding surface was more effective as the total length of the bonding surface reinforcing plate 200a was shorter.

FIG. 7 is a graph showing energy dissipation capacity using FIG. 6. FIG. Referring to FIG. 7, when the second model is compared with the reference value, the energy dissipation capacity is improved by about 20%, which is the most effective. In addition, all of the other models showed improved effects compared to the reference values.

FIG. 8 is a perspective view of the bonding face reinforcing plate 200b according to the second embodiment, and FIG. 9 is a perspective view of the bonding face reinforcing plate 200b of FIG. 8 arranged and combined. Referring to FIGS. 8 and 9, the bonding surface reinforcing plate 200b is formed of a rectangular portion 210b and a trapezoidal portion 225. At this time, the bonding surface reinforcing plate 200b may be formed as a single unitary shape, which is differentiated and named so as to specifically divide the shape.

The rectangular portion 210b has the same shape as that of the first embodiment except for the difference in dimensions. The trapezoidal portion 225 has a shape in which the starting portion has the same width as that of the rectangular portion 210b but is gradually reduced in width. At this time, the rectangular portion 210b and the trapezoidal portion 225 are formed to have the same thickness.

At this time, the total length of the bonding face reinforcing plate 200b and the length of the other side of the rectangular portion 210b may vary due to design changes and the like. However, according to the results of the finite element analysis, the total length of the bonding face reinforcing plate 200b does not exceed the above-mentioned height D, and the length of the other side of the rectangular portion 210b does not exceed the above-mentioned width B Do not. Particularly, the rectangular portion 210b and the trapezoidal portion 225 are preferably formed to be 0.5 times the thickness of the raft flange 111.

10 is a perspective view of the bonding face reinforcement plate 200c according to the third embodiment, and Fig. 11 is a perspective view of the bonding face reinforcement plate 200c of Fig. 10 arranged and combined. 10 and 11, the joint surface reinforcing plate 200c is formed of a rectangular portion 210c extending in the same width as the raft flange 111. As shown in Fig. The rectangular portion 210c has the same shape as that of the first embodiment except for the difference in dimension.

The length of the bonding face reinforcing plate 200c, that is, the length of the other side of the rectangular portion 210c, can be changed by design change or the like. However, according to the results of the finite element analysis, it is preferable that the length of the rectangular portion 210c does not exceed the height D. [ Particularly, the length of the bonding surface reinforcing plate 200c is not less than the width B of the cage of the cage 111, and the height D of the portion of the cage 113, 0.4 times or less.

In addition, the frame for a building according to the embodiment of the present invention further includes a rib plate 230. The rib plate 230 is vertically coupled to each of the bonding surface reinforcing plates 200a, 200b, 200c and the expandable end plate 114, respectively. For example, the rib plate 230 is joined at portions corresponding to both sides orthogonal to each other in a right triangular shape. As a result, the vicinity of the bonding surface can be further strengthened, and the stress in the vicinity of the bonding surface can be further reduced.

6, the stress in the vicinity of the joint surface is reduced due to the addition of the joint surface reinforcing plate 200a, but the stress acting on the panel zone 250 is not changed. Accordingly, the frame for a building according to one embodiment further includes a column web reinforcement plate 300a that can reduce the stress of the panel zone 250.

The column web stiffener plate 300a is disposed on the side of the column web 123 adjacent to the expandable end plate 114 and in particular on the panel zone 250 defined by the column stiffener 124 .

12 and 13 are perspective views showing deformable shapes of the column web reinforcing plates 300a and 300b.

First, in FIG. 12, the column web reinforcing plate 300a according to the first embodiment is a C-shaped steel plate having the same inner and outer curvatures. At this time, the width and thickness of the C-type steel plate are constant, and both ends thereof are semicircular. Particularly, the reason why the C-type steel plate is used is that it can easily absorb it in the form of elastic energy corresponding to the tensile force or compressive force externally applied due to its own shape. As a result, the C-type steel sheet can reinforce the rigidity around the columnar web 123 to which the C-type steel plates are arranged.

However, the joining position is such that the overall shape of the C-shaped portion is directed outwardly of the cage portion 110 and the pillar portion 120 in which the intermediate convex portions are fixedly joined to each other, It is possible to maximize the energy available.

As a second embodiment, the column web reinforcing plate 300b of FIG. 13 is a symmetrical C-shaped steel plate having different inward and outward curvatures, and the width of the intermediate convex portion is particularly narrow. However, the width can be adjusted through design changes such as inner or outer curvature adjustment.

13, it is preferable that the joining position is directed to the outside of the cage portion 110 and the cage portion 120 in which the convex portion is fixedly joined, and the overall shape is disposed in an upper right room with an inclination from the joining face. Referring to FIG. 2, the column web reinforcing plate 300a is disposed in an upper right room while forming an inclination angle of a predetermined angle with the joining face. That is, both ends of the column web reinforcing plate having the C shape as a whole are arranged and joined in the diagonal direction of the panel zone 250.
On the other hand, the center of gravity of the column web reinforcing plates 300a and 300b according to the first and second embodiments is disposed at or near the center of the panel zone 250 in particular. That is, the column web reinforcing plates 300a and 300b are arranged in a diagonal direction connecting the two edges of the panel zone 250.

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On the other hand, according to the results of the finite element analysis, it was confirmed that the stress value of the panel zone 250 was reduced when the column web reinforcement plates 300a and 300b were further disposed in the panel zone 250.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

110: raft portion 120:
121: Flange inside the column 121a: Expanded flange inside the column
122: column outer flange 123: column web 1
124: column stiffener 111: raft flange
113: Raft web 114: Expandable end plate
200a, 200b, 200c: bonding surface reinforcing plates 210a, 210b, 210c:
220: tapered portion 225: trapezoidal portion
230: rib plate 250: panel zone
300a, 300b: column web reinforcement plate

Claims

1. A frame for a building comprising a raft portion for supporting a roof, and a column portion fixed to the raft portion at one end and fixed to the ground at the other end,
The raft portion being vertically coupled to the raft web and the raft flange to form a joining surface with the joining portion, And an expandable end plate that is further extended in both lateral and vertical directions of said raft web portion,
The column portion having a column internal expandable flange coupled with the expandable end plate; And a column stiffener vertically coupled to the column internal expandable flange,
And a joint surface reinforcement plate having an end disposed in contact with the expandable end plate and a bottom surface coupled to an outer surface of the raft flange,
Wherein a central line passing through the center of the column stiffener on the basis of the thickness passes through the center of the reinforcing portion formed by the combination of the raft flange and the joint surface reinforcing plate.

The method according to claim 1,
Wherein the joint surface reinforcing plate comprises: a rectangular portion extending in the same width as the cage; And
And a tapered portion extending from the rectangular portion, the width of which starts to extend is smaller than the length of the width of the rectangular portion, and the width gradually decreases,
Wherein the tapered portion is smaller than the thickness of the rectangular portion.

3. The method of claim 2,
Wherein the rectangular portion is formed to have the same thickness as the raft flange, and the taper portion is formed to be 0.5 times the thickness of the raft flange.

The method according to claim 1,
Wherein the joint surface reinforcing plate comprises: a rectangular portion extending in the same width as the cage; And
And a trapezoidal portion extending from the rectangular portion and having a width gradually reduced.

The method according to claim 1,
Wherein the joint surface reinforcing plate is formed as a rectangular portion extending in the same width as the raft flange,
Wherein the length of the joint surface reinforcing plate is greater than or equal to the width of the cage and less than or equal to 0.4 times the height of the cage.

6. The method according to any one of claims 2 to 5,
And a right triangular rib plate vertically coupled to the joint surface reinforcing plate and the expandable end plate, respectively.

The method according to claim 1,
In the panel zone formed by the column stiffener
And a column web reinforcement plate which is formed in a C shape having the same inner and outer curvatures and in which both ends of the C shape are arranged and joined in a diagonal direction of the panel zone.

The method according to claim 1,
In the panel zone formed by the column stiffener
A columnar web reinforcement plate having a symmetrical C-shape having a different inner and outer curvature but narrower widths of the convex portions and both ends of the C-shape being arranged and joined in diagonal directions of the panel zones; Frames for buildings.

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