NO884951L - MOBILE TUNNEL SYSTEM. - Google Patents

Abstract

A mobile underpass system is composed of a plurality of sections (B) which are interconnected by means of fastening devices and each section comprises a bottom frame (11) and a top frame (12) which are parallel to each other and which are joined to a number of uprights ( 15) which are arranged mutually parallel between the frames along the side surfaces of the section. The bottom frame and possibly the top frame and the side surfaces are completely or partially covered. Each section forms a polygon in plan section, and the posts (15) in each section are arranged so that the center distance (a) between a plurality of the posts (15) and preferably between all posts , is equal in size along the peripheral side circumference of the section. The fastening devices comprise bracing brackets (17) which are fastened to the underside of the beams (13, 14) in the top frame and in the side surfaces of the uprights (15), and in each bracing bracket a hole (18) is formed for passing a fastening bolt for fastening to flush bracing brackets (17) on an adjacent section of the system.

Description

The present invention relates to a mobile pedestrian tunnel system comprising a plurality of sections which are interconnected by means of fastening devices and where each individual section comprises a bottom frame and a top frame which are parallel to each other and which are joined together by means of support means in the form of a number of posts which are arranged parallel to each other between the frames along the side surfaces of the section, the bottom frame and possibly the top frame and the side surfaces being completely or partially covered.

Underpass systems are used to protect people passing construction sites such as construction sites and remediation areas. The pedestrian tunnel systems are also used for footbridges such as pedestrian crossings or pedestrian underpasses, or for example for erecting living walls, or for reading sheds in connection with stops for public means of transport.

The underpass systems used today to protect people passing by construction sites and areas where older buildings are being rehabilitated are rectangular structures that are placed at street level. The load-bearing parts in the underpass sections usually comprise a construction in the form of frames with attached studs between the frames. The frames usually consist of welded beams. In the frames, stiffening beams can also be arranged parallel to each other. Between the bottom sides of the top beams and the stud sides that face the interior of the tunnel section, bracing beams are often arranged which are welded in at an angle. Full-covering steel plates are also mounted on both the top and bottom frames as well as in the side openings between the uprights. The bottom frame is covered with expanded metal which may represent a general safety risk, e.g. for people with high-heeled shoes, and that it affects the section's stability. The top frame is occasionally covered with corrugated steel sheets.

The pedestrian tunnels used today have largely been developed from the usual construction of transport containers where special connecting bodies in the form of so-called prefabricated ISO corners are welded between the frame beams in the corners. Connection holes are also arranged in each of the three side surfaces of the ISO corners facing outwards. During the manufacture of the container, such an ISO element is thus welded into each corner. The above-mentioned holes in the ISO corners are used to interlock the containers that are stacked on top of each other and in width, using clamping bolts or so-called elephant hooks. This is necessary when the containers are transported on open ship decks.

It is the above interlocking design that has become

adopted during the design of pedestrian tunnels for privacy. However, this container construction means that the weakest points in the supporting part, i.e. adjacent to the welding joints between the construction's ISO corners and beams, are located on the side of the vertical support beams. In the event of vertical or lateral stress as a result of falling heavy objects such as building parts, there is a great danger that when the structure is bent over a certain limit, breakage will occur in these welding joints next to the vertical support beams. In such a case, there will be no underlying support struts that can resist and bend down and absorb compressive loads, and the structure is in danger of breaking down completely. The people who happen to be inside the pedestrian tunnel will in such a case be in great danger.

When pedestrian tunnels are to be set up for straight stretches such as along a pavement, the sections are lined up one after the other and locked together via the holes in the corner elements, the so-called ISO corners, using the above-mentioned elephant hooks.

When a pedestrian tunnel is to be set up where there are bends and differences in height, i.e. in hilly terrain, adaptation problems arise which must be solved on site by improvisations. This is usually carried out using different materials, and most often with wooden materials in the form of beams and boards. The same improvised solutions are used if, for example, the pedestrian tunnel is to be connected with e.g. crossing pedestrian tunnels. There is also no satisfactory solution if the underpass is to form a connection between building floors on different levels or if traffic is to take place on top of the underpass. Furthermore, there are no known satisfactory systems that can form the connection between the floors.

The above-mentioned improvised solutions also represent a significant safety risk since the joint areas between the sections are usually not satisfactorily secured against falling objects or displacement. Furthermore, the above-mentioned pedestrian tunnels cannot be used in free span without extensive and expensive reinforcements in the form of beams on which the tunnels are mounted. The connection is therefore only carried out by placing elephant hooks in the aforementioned corner holes in two adjacent sections.

Against this background, there is a need for a pedestrian tunnel system with standardized measurements so that the sections can be connected more easily in a number of different possibilities.

Furthermore, it is an aim of the invention to produce a pedestrian tunnel system which satisfies the safety requirements that must be set for such facilities, also in the areas where the sections in the system are interconnected, as well as in the areas where the pedestrian tunnel turns or bends.

It is also an aim of the present invention to produce a tunnel system which can be mounted, also in free span, by means of universal fittings which are easy to mount.

The tunnel system according to the present invention is characterized by the fact that each section in plan section forms a polygon, that the studs in each individual section are arranged so that the center distance between a majority of the studs, and preferably between all studs, is equal along the section's peripheral side circumference, and that connecting means in the form of bracing fittings are attached to the underside of the beams in the top frame and the side surfaces of the uprights, and the bracing fittings are equipped with means for attachment to bracing fittings on adjacent sections of the system.

With the tunnel system according to the invention, it is achieved that the load-bearing structure, which is made up of the beams in the top and bottom frame and the uprights between the frame parts, has a much greater load-bearing capacity and resistance to bending before a collapse occurs in the structure, when it is hit by heavy falling objects. This is because the uprights are now fully welded to the beams in the bottom and top frame, i.e. the welding joints are no longer located in the frame's free beam span outside the attachment point between beams and uprights, as is the case for the above-mentioned ISO corners. Moreover, the solution according to the present invention enables several sections to be connected in a number of optional locations without drilling or designing holes or grooves in support beams and uprights. The connecting fasteners themselves are placed adjacent to the fasteners between support beams and uprights and help to prevent the connected sections from being displaced horizontally or vertically in relation to each other.

According to a preferred embodiment of the present invention, each stiffening fitting, which is placed parallel to the side surfaces of the section and which comprises a hollow beam-shaped body or a flat plate body, is arranged set back at a distance from the plane which coincides with the outer plane of the section. The stiffening fitting is preferably placed at a distance of approx. 10 mm from the outer plane of the section. With this solution, one achieves that when two sections in the system are placed next to each other, the bracing fittings do not bump against each other, which would otherwise prevent or weaken the connection of the sections.

According to a further preferred embodiment of the tunnel system according to the invention, the fastening device comprises a profiled plate-shaped fitting which is bent to form two side parts which in cross-section form an angle of approximately 90° with each other, and the plate-shaped fitting is designed with through holes, preferably two in each side part, as the holes align with corresponding holes in the sections' stiffening fittings when the fastening device is correctly positioned, and the fastening fittings are arranged to wrap around the side edges formed by the adjacent corners of two sections, and the sections are further stabilized in position in relation to each other by bolts which is inserted through the aligned holes in the fixing bracket and stiffening bracket.

The above-mentioned brackets can in reality be used as a universal bracket when connecting the sections and gives the tunnel system additional strength against displacements, as well as reinforcing against deflections of the construction itself in the event of a fall.

According to a further preferred embodiment of the present invention for assembly in free span, a fastening fitting for joining the bottom frames of the sections comprises a plate-shaped body which is bent to form two side parts which form 90° to each other in cross-section, while in one side part two holes are designed which, with the fixing bracket in the assembled position, align with the holes in the opposing sections' stiffening bracket, while the other side part is further bent so that together with one side part in cross-section it forms a U-shape, while a middle end part of the further bent part is cut out to form a claw-shaped fastening member which, when assembled, forms an overarching connection with the adjacent beams in the bottom frames of two adjacent sections.

With this design, the fixing bracket can effectively prevent the bottom parts of two adjacent sections from bending away from each other when the tunnel system is mounted in free span.

To explain the invention in more detail, reference should be made to the accompanying drawings, in which: Fig. 1 shows a perspective view of a basic model (A) of a section in the foot tunnel system according to the invention with a square plan section. Fig. 2 shows a perspective view of a pedestrian tunnel section (B) in an embodiment with a rectangular plan section. Fig. 3 shows a joint section (C) in an embodiment with a plansite as an isosceles triangle. Fig. 4 shows a further embodiment of a pedestrian tunnel section (D) with a plan section in the form of an equilateral triangle. Fig. 5 shows an embodiment of a section (E) with a plan section in the form of an equilateral hexagon. Fig. 6 schematically shows a perspective view of a section (F) with a built-in spiral staircase.

Fig. 7 shows a side section of a straight stair section (G).

Figs. 8-10 show perspective views of three designs of fastening fittings for further strengthening of the joining of adjacent tunnel sections. Fig. 11 shows in a partial section how a reinforcement bracket is placed when joining two adjacent sections in the foot tunnel system according to the invention. Fig. 12-16 show plan sections of pedestrian tunnel systems according to the invention in the form of various assemblies of the base sections according to fig. 1-4. Fig. 17 shows a side section of an embodiment of the foot tunnel system in free air span in the form of a footbridge with two rectangular sections (B) and stair sections of which one stair section according to Fig. 6 is outlined in two alternative directions.

For the assembly of the pedestrian tunnel system according to the invention, which is shown in several versions in Figures 12-16, a number of base sections (A-G) are used which will be described in more detail in what follows.

In fig. 1 shows a perspective view of a pedestrian tunnel section (A) with a square plan section which can be used in the pedestrian tunnel system according to the invention. The section consists of a bottom frame 11 and a top frame 12 and uprights 15. The bottom and top frames are parallel and consist of pairs of parallel beams 13,14 (of square steel) which are joined, preferably by welding. In addition, parallel stiffeners (not shown in the drawing) can be welded in between the beams at the bottom and the top frame. The uprights 15 are placed between the frames and welded to the beams 13,14. The center distance (a) between the studs is the same around the entire side circumference of the section. Between the beams in the top frame 12 and each of the four uprights, adjacent to the attachment point between the beams and uprights, two fastening devices are arranged in the form of stiffening fittings 17. The fittings 17 can be made of hollow beam-shaped bodies or plate-like bodies which are fixed as by welding. The bracing fittings 17 are placed in an inclined position between the side edge of each strut and the underside of the adjacent frame beam. The fittings are therefore placed adjacent to the welding fasteners between the girders and the frame. For the construction shown in figure 1, eight bracing fasteners 17 are thus arranged between beams 13,14 and uprights 15. The bracing fasteners 17, which are longitudinally arranged parallel to the planar side surfaces of the section, are also arranged set back from the side surfaces of the section, and preferably set back 1 cm, so that the bracing fasteners on two adjacent section sides during assembly do not bump into each other when the sections are placed next to each other.

Furthermore, a hole 18 is arranged through each bracing attachment 17, which is drilled perpendicular to the plane through the planar side surfaces of the section. The bracing fasteners 17 help to reinforce the construction's shock-absorbing properties and that they are used when adjacent sections 19,20 (see fig. 12) in the system are to be connected together. When the sections are placed next to each other, the holes 18 in the adjacent connection fasteners 17 align with each other and a clamping device is introduced such as a bolt with a threaded end where a nut is attached so that the sections are screwed together.

Stiffening fasteners are also placed in connection with the studs' welding fasteners with the beams in the bottom frame. These can advantageously be welded on after you know the structure and composition of the tunnel system so that you avoid the bracing fasteners forming tripping edges that could pose a safety risk.

In addition, a fully drawn steel plate (not shown) is placed on top of the top frame and a corresponding fully covering (i.e. without openings) and fully drawn (i.e. fully welded) steel plate on top of the beams of the bottom frame. On the top frame 12, organs such as lifting lugs 16 are arranged which are used during handling and lifting of the sections. The lifting lugs 16 are also used to secure safety posts for railings in the event that there is to be passenger traffic on top of the top frame, and they can e.g. is used to fix the grid on the roof of the section.

With the present construction, it is achieved that the bracing fasteners 17 act as shock absorbers at the moment of loading when the section is subjected to overloads from above and/or from the side.

In fig. 2 shows an elongated section (B) with a rectangular plan section of the foot tunnel system according to the invention. Incidentally, it is this basic section that is used the most in practice. The construction of the section itself corresponds to the design of the section shown in fig. 1, as it consists of parallel top and bottom frames 11,12 of welded together pairs of parallel steel beams 13,14 and uprights 15 which are welded in between the frames. In the longitudinal direction of the section, further transverse frame beams (hidden in the drawing) and uprights 15 are arranged at regular intervals. According to the invention, these frame beams and uprights are arranged with a center distance (a) that corresponds to the center distance between the uprights 15 at the section's short end (b) and they have same dimensions as beams and studs in the rest of the frame. In addition, parallel braces (not shown in the drawing) are welded in between the beams at the bottom and the top frame. Adjacent to the attachment points between top frame braces 13,14 and uprights, it is in the same way as for the basic model in fig. 1, inclined bracing brackets 17 are arranged where holes 18 are drilled across the side surfaces of the section. In each corner of the section, there are thus two such bracing fasteners, while in connection with the studs placed on the long sides of the section, between the corner studs, there are three connection fasteners, i.e. two are arranged parallel to the longitudinal direction of the section while one is arranged across . As for the basic model according to fig. 1, full-covering steel plates can also be arranged on top of the top frame or the bottom frame, where corrugated sheets are used on top of the top frame, and lifting lugs and possibly support posts for railings are arranged at the points along the section's side beams where uprights and frame beams are welded in. The elongated section is in reality a longitudinal multiple of the square basic model shown in fig. 1. The center distance between the studs placed lengthwise by the section is therefore the same as the center distance on the short sides of the section, and that the frames are parallel, i.e. that the studs have the same height. Thereby, the transverse end of an adjacent section can be optionally joined to each of the longitudinal openings delimited by the uprights in the described section.

When two sections are now placed next to each other as described above, for example, the previously mentioned holes 18 in the top frame's stiffening fasteners 17 align so that a continuous fastener can be inserted, such as a bolt with a threaded end where a nut can be placed so that the sections can be screwed to each other.

The two above-mentioned sections with square or rectangular plan section (A,B) is suitable for pedestrian tunnel systems that must turn at right angles. However, there may be cases where the tunnel system should bend in an arc around a house corner or where the tunnel sections should be connected at other non-right angles. In order to avoid the temporary solutions mentioned above when connecting sections, for example when the system swings, so that safety is maintained, according to the invention, various joint sections are arranged.

Fig. 3 shows a joint section with a plane section as an isosceles triangle (C), the angle (alpha) between the legs of equal length 22,23 being e.g. 30°. In this case, the bottom and top frame are made of the same materials and just as powerfully dimensioned as in the two previous examples, except that the basic section is triangular. The center distance between the uprights along the equally long sides 22,23 corresponds to the center distance between the uprights in the previously mentioned sections. In connection with each of the top frame's two equally long legs, stiffening brackets 17 with the same design as previously shown are attached between the beams and the uprights, so that, for example, the short side of a longer straight tunnel section can be joined with the joint section. The joint section can also be placed next to and connected to the long side of a longer rectangular section. The joint section is otherwise equipped in the same way as for the preceding examples with lifting lugs, fully drawn panels in the bottom and top frame as well as arranged for the installation of side panels, possibly with openings for the insertion of windows, the installation of railings, or lattice fencing etc.

In fig. 4 shows a joint section which has a plan section as an equilateral triangle (D). Since the center distance (a) between the studs is the same as for the other sections, there are optional connection possibilities to the section's three side surfaces. In fig. 5 shows a further embodiment of such a joint section designed with a plan section as an equilateral hexagon (E). The side surfaces of each of these sections (fig. 4 and 5) are dimensioned in the same way as the side surfaces of the other sections in terms of lifting lugs, bracing attachments between beams and uprights, the solid steel plates on the top and bottom frames, the covering of the side walls with plates, gratings, possibly .setting up railings. In this design of the tunnel section, the connection or splicing with other of the mentioned sections can therefore take place via all six equally sized side surfaces.

On all the designs mentioned, the side surfaces are standardised, i.e. that during the connection, the bracing fasteners on two or more adjacent sections will be flush with each other so that the sections can be joined by means of fastening bolts that are inserted through the flush holes in the bracing fasteners. Such fastening bolts are usually threaded bolts with corresponding nuts, so that the sections can be screwed exactly together.

In fig. 6 shows a side section of a section (F) where a spiral staircase 24 is built in, where the support column 25 for the steps itself is fixed to frame beams in the middle of the section. An opening has been designed in the top frame for, for example, egress to or continuation in an overlying further staircase section or to the roof of an adjacent tunnel section. Also on the stair section there are lifting lugs (not shown) for moving the section. In an alternative embodiment, the stair section can form part of an elongated rectangular tunnel section where the stair section is placed at one end within the base section with a square plan section.

In fig. 7 shows a schematic perspective view of a section (G) for a straight staircase, with the side section of the section forming a parallelogram. The stair section is shown in the figure in a raised inclined position in relation to an imaginary horizontal plane (H). Bottom and top frames 11,12 are parallel. Both short ends of the stair section 2 6,27 are designed with a standardized opening, i.e. that the center distances between the corner posts are the same as for the other sections, and that there are connection brackets so that the stair section in an inclined position can be connected directly to the other previously described sections.

For additional strengthening of the joining of the sections in the system according to the invention, additional fastening fittings can be used which are placed around the joint area where the corners of two adjacent sections abut against each other. Three different types of fixings for this purpose are shown in fig. 8-10.

The mounting bracket according to fig. 8 comprises a plate-shaped body which is bent to form two side parts 28,29 which in a cross-section form an angle of 90° with each other. Two through holes 30,31 are formed in the plate-like body, preferably two in each side part, so that the holes align with corresponding holes in the sections' stiffening fittings when the fittings are correctly positioned. The sections are stabilized in position relative to each other with threaded bolts which are inserted through the aligned holes 30,31 in the fixing bracket and stiffening bracket, after which the bracket is fixed by screwing a nut onto the bolt.

In fig. 9 shows a fitting in another embodiment, and it appears that one side part 32 is identical to the corresponding part 28 of the fitting shown in fig. 8. The second side part 33, however, forms a claw-shaped fastening element in that the side part is further bent so that the fitting forms a U-shaped cross-section, and a middle part 34 of the side part is cut out. Thereby, the claw-shaped fastening means can form a comprehensive connection against two opposing bottom frame beams or studs on two adjacent sections. This fastening device is used to hold the sections' bottom frame beams together during assembly of a tunnel system and is necessary to use during assembly in free span.

Another embodiment of a fastening fitting is shown in fig. 9. The one side part 35 with attachment holes 30,31 which must be flush with corresponding holes in the stiffening fitting in the sections, is identical to the corresponding side part 28 shown in fig. 8. The second side part 36, however, only comprises an elongated flat plate as shown in the figure, to form a hold around opposing beams or posts in the tunnel system.

The two mounting brackets shown in fig. 8 and 10 can be used to join both the bottom and top frames of the sections. This also applies to the sections that do not have a square plan section, i.e. that the fittings e.g. can also be used when joining a section with an isosceles cross-section to the short end of a section with a rectangular cross-section. The fittings are of course also used to join two sections that are mounted on top of each other. The fittings are also used when the straight sections are to be connected in free span. The mounting bracket according to fig. 9, however, is only used for joining the bottom frames on adjacent sections. For assembly in free span, it is mainly straight sections that are relevant for connection.

In fig. 11 shows a partial section of how a reinforcement fitting of the above-mentioned types is placed for joining two adjacent sections 37, 38 in the tunnel system according to the invention. It is shown how the sections' top frames 12,12' are joined by a fitting according to fig. 8 is placed next to the two sections' beams and uprights 15,15' in the corners, and the four fastening bolts 39-42 are inserted into the holes of the fittings and further into the respective holes 18 in the stiffening fittings 17 on the respective opposing sections 37,38. The fittings shown thus prevent the sections from being displaced vertically or horizontally in relation to each other.

In fig. 12-16 shows (on a greatly reduced scale) in plan section a number of alternative executions of pedestrian tunnel systems which are built up from the above-mentioned pedestrian tunnel sections (A-E). It will be seen that the system can be constructed with optional and almost countless modifications using the described sections with square, triangular, rectangular and hexagonal cross-sections.

In fig. 12 shows, for example, a plan section of how a pedestrian tunnel junction can be constructed using a hexagonal section (E), with three side branches starting from this in the form of two rectangular (B) sections and a square (A) section as the start of tunnels

further branches in different directions.

In fig. 13 shows an example of how a U-turn in a pedestrian tunnel system can be constructed using rectangular sections (B) and a series of isosceles sections (C). Fig. 14 shows how an arc-shaped swing formation can be built up using a square section (A) and isosceles sections (C), as these lead on to, for example, rectangular sections (B). Fig. 16 shows another example of a pedestrian tunnel junction where the equilateral section (D) is connected with rectangular sections

(B) .

In fig. 16 shows how a pedestrian tunnel (A) can be expanded

into two parallel paths (B) by means of three interconnected equilateral sections (D).

Consequently, with these few sections, one can adapt the pedestrian tunnel system to any purpose with respect to directions, turns, crossing pedestrian tunnel systems, bridges, stairs, etc.

Fig. 17 shows a side section of a pedestrian tunnel system in a free air span in relation to a horizontal surface (H) in the form of a footbridge comprising two rectangular sections (B) shown in figure 2 and two stair sections (G) shown in fig. 6. Fixing bracket 46 (according to fig. 8-10) is mounted between the two rectangular sections (B). One stair section (G) is shown in two alternative directions. The stair sections (G) can thus be turned both ways, i.e.

both upwards 44 and downwards 45 by only turning the section horizontally.

Claims (8)

1. Mobile tunnel system comprising a plurality of sections which are interconnected by means of fastening devices and where each individual section comprises a bottom frame (11) and a top frame (12) which are parallel to each other and which are joined together by means of support means in the form of a number of uprights (15) which are arranged parallel to each other between the frames along the side surfaces of the section, the bottom frame and possibly the top frame and the side surfaces being completely or partially covered, characterized by that each section in plan section forms a polygon, that the uprights (15) in each individual section are arranged so that the center distance (a) between a majority of the uprights (15), and preferably between all uprights, is the same along the peripheral side circumference of the section, and that connecting means in the form of stiffening fittings (17) are attached to the underside of the beams (13,14) in the top frame and the side surfaces of the uprights (15), and the stiffening fittings (17) are equipped with means for attachment to stiffening fittings (17) on adjacent sections in the system . 2. Mobile pedestrian tunnel system in accordance with claim 1, characterized in that a through hole (18) is designed in each bracing bracket (17), and the holes (18) in the adjacent brackets (17) of two joined sections are aligned with each other for carrying out a bolt, for example a threaded bolt with an associated nut, for firmly connecting the adjacent sections. 3. Mobile pedestrian tunnel system in accordance with claim 1 or 2, characterized in that the bracing fitting (17) comprises a hollow beam-shaped body or a flat plate body, the fitting in the longitudinal direction being arranged set back at a distance from a plane which coincides with the outer plane of the section. 4. Mobile pedestrian tunnel system in accordance with claim 1, characterized in that at least one of the sections in the system forms a rectangular plan section, and the center distance (a) between the uprights (15) is equal along the section's entire circumference. 5. Mobile pedestrian tunnel system in accordance with claim 1, characterized in that each fastening device comprises a profiled plate fitting which is bent to form two side parts (28,29) which in cross-section form an angle of approximately 90° with each other, and The plate-like body is designed with through holes (30,31), preferably two in each side part, as the holes align with corresponding holes in the sections' stiffening fittings (17) when the fittings are correctly positioned, and the fitting is arranged enclosing around the corners where two adjacent tunnel sections meet against each other, and fixing bolts are inserted through the aligned holes (30,31,18) in the fixing bracket and stiffening bracket (17). 6. Mobile pedestrian tunnel system in accordance with claim 1 or 5, where the pedestrian tunnel system is mounted in a free span, for example a pedestrian crossing, characterized in that a fastening fitting for joining the bottom frames of the sections together comprises a plate-shaped body which is bent to form two side parts ( 32,33) which form an angle of approx. 90° with each other in cross-section, with two holes (30, 31) formed in one side part (32) which, with the mounting bracket in the mounted position, align with the holes (18) in the opposing section's bracing bracket (17), while the other side part (33) is further bent so that the bracket forms a U-shape in cross-section and a middle part (34) of the side part is cut out to form a claw-shaped fastening means which forms a comprehensive connection with the adjacent beams (14) in the bottom frames (11) of two adjacent sections. 7. Mobile pedestrian tunnel system in accordance with one of the preceding requirements, characterized by a stair section which in side section has the shape of a parallelogram, the section's two short ends (26,27) are designed so that the center distance (a) between the uprights is the same as the center distance (a) between the uprights in the other sections, so that the stair section can optionally be inclined in an upward or downward (44 or 45) direction for connection with the other sections. 8. Mobile pedestrian tunnel system in accordance with one of the preceding claims, characterized in that a staircase (24) is arranged between the section's bottom frame and top frame within the base section with a square plan section, the staircase comprising a spiral staircase where a support column (25) is attached to the center of the frames and steps are attached to the column (25) so that the steps form a spiral pattern, and an opening is designed in the top frame for exit to the upper side of the top frame.