HRP20000671A2 - Tunnel lining made of prefabricated reinforced concrete elements and process for its manufacturing and installing - Google Patents

Description

The field to which the invention relates

The invention relates to a tunnel lining system using prefabricated arched self-supporting waterproofing concrete elements, which also serve as formwork for concrete filling. With this invention, savings are achieved in tunnel work time, the amount of shotcrete as a base for the waterproofing layer is reduced, and the waterproofing itself, with this system, is eliminated as a phase of work in the tunnel. By applying a tunnel lining made of prefabricated reinforced concrete elements, the tunnel excavation profile is reduced.

According to the international classification of patents, the subject of the invention is classified and marked with the classification symbol E 21 D, 11/08, 11/18, 11/40.

Technical problem

The technical problems solved by this invention of tunnel lining with factory-made prefabricated reinforced concrete arch elements are:

1. Production of arc elements in the factory,

2. Assembly of elements under the "ceiling",

3. Interconnection of elements,

4. Waterproofing layer of the upper surface and sealing of joints, with fire protection of the seal,

5. Installation of circular self-propelled scaffolding in the tunnel i

6. Automation of work processes.

State of the art

In our country, there is no elaborate system of prefabricated tunnel lining, but the tunnel lining is performed monolithically using sliding formwork, so that first a layer of approximately 20 cm of shotcrete is made, waterproofing is carried out on it, and then monolithic tunnel lining is performed in sliding formwork. and the progress is conditioned by the length of the formwork and the necessary time for the concrete to harden after installation. In the world, as far as I know, there is a solution of prefabricated lining only for hydrotechnical tunnels, but it is completely different from this proposed invention.

Presentation of the essence of the invention

Manufacturing of arc elements in the factory

A special technical problem is the production of formwork, which enables the execution of elements in a geometric shape that follows the planar curvature of the tunnel axis, since it is impossible to rotate the rigid circular floor between the two surfaces of the roller.

The solution was found in such a way that the floor surface (13) in the part that closes the formwork from the bottom side is made of segments (13.1) that are connected to each other by a rubber joint (13.2), which enables changing the radius of curvature and turning the circular segment into an ellipsoidal segment. The reduction of the dimensions of the element due to concrete shrinkage was solved by the well-known technological process of making a concrete mixture with additives for concrete expansion.

Installation of elements under the "ceiling"

Assembling elements weighing five tons under the tunnel vault, while the free space between the element and the tunnel wall is only a few centimeters, is a very difficult technical problem, which we solved with a self-propelled scaffolding system for transversely circular pulling of elements.

Scaffolding (1.1, 1.2, 1.3, and 1.4) consists of a central part with a free opening for the passage of construction site vehicles, and side parts (2.1, 2.2), which serve for the reception and assembly of the lower cladding elements (A and E), and the reception and launching the upper cladding elements (B, C and D) onto the upper circular grid (1.1), on which the rollers (1.2 and 1.3) are placed for the reception, longitudinal and transverse transport of the assembly elements (B, C and D).

The symmetry of the scaffolding enables the reception, launching and assembly of elements from the left and right sides depending on the conditions on the construction site, as well as the assembly of the tunnel lining, which consists of three elements in cross-section, all according to the same details and procedures.

The description of assembly, method of attachment and ensuring stability applies to both systems, which are given with the description of the overview drawings.

Interconnection of elements

Interconnection of elements is possible in two basic ways, wet and dry. The wet process involves injecting cement mortar, or joint compound, into the holes left for this purpose on the connecting surfaces of the elements. After hardening of the injection mass, the element takes over the load. The dry process, which is applied in this technical solution, requires precise manufacturing of the elements in the factory, and the protrusions and grooves should be coated with rubber of appropriate hardness, which cancels out inaccuracies in the performance of reinforced concrete elements by its deformation.

Pre-assembled prefabricated element as a waterproofing element of the tunnel lining

After setting and collecting the concrete in the warehouse at the concrete factory, the waterproofing coating of the upper surface will be carried out with a polymer-cement coating, that is, with any quality waterproofing, or add impermeability additives to the concrete mass, thus protecting the penetration of moisture from leachate. Rubber profiled according to the concrete shape is glued to the sides, which serves as an adjacent element, and especially as a waterproofing element. Rubber protection against fire is performed with a special permanently elastic putty that is heat-resistant up to 300°C.

Precast prefabricated element as formwork for concrete filling between the shell and tunnel lining

Since a longitudinal force has been applied to the mounted arch and the arch is supported on adjustable screw supports, concreting of the arch bed and the space (cavity) between the mounted arch and the tunnel cap is started, so that the concrete filling completely fills the space between the tunnel cap and the mounted arch. Infill concrete can be reinforced or unreinforced, according to the conditions in the technical documentation.

If necessary, there is a possibility of separating the arch structure and the concrete filling from the tunnel shell by previously covering the tunnel shell with a compressible material of the thickness of the dilation provided by the project. In addition to the role of expansion, the compressible material also plays the role of lost formwork.

Installation of circular self-propelled scaffolding in the tunnel.

The lower part of the scaffolding (1.4) is classically assembled into a drive unit using a truck crane, and the upper circular part of the scaffolding (1.1) is unloaded in one piece from the truck and placed transversely on the axis of the tunnel next to the already mounted part. Using the hydraulic motor over the console, with the pre-installation of mounting elements "E" and "D" on the slides, it rises to the height of the bearings on part (1.4), rests on the temporary tubular scaffolding, which is pulled under the circular support, and stabilizes the already assembled lower the part is pulled under the circular support by its own drive. The connection is made with screws, the temporary support from the light tubular scaffolding is dismantled and the mobile scaffolding is ready for work.

Automation of work processes

The automation of the work processes is solved by means of remote control of all the actions of accepting the assembly element, dragging it into the axis of the circular assembly self-propelled grid, and placing it in the definitive position. Then releasing the scaffolding and moving the scaffolding to a new working position. In the new working position, he first accepts the assembly element "E" on one launch element (2.1), and on the other launch element "carriage" to accept the pipe for transporting concrete, concreting the space between the calotte and the assembled arched vault from prefabricated prefabricated reinforced concrete elements and after concreting is finished, the "carriage" is removed and the assembly of the next arch with element "E", which until now served as ballast for the smoothest concreting work, can begin. The automation of these work processes consists in the impossibility of starting actions that could threaten the security of the server, that is, the safe and correct execution of the action in progress.

Description of overview drawings

Drawing number 1a and 1b shows the mounting element "E" and "D" on the launch slides (2.1). From this position, element "E" is raised to a vertical position and moved to the axis of the assembly grid. By moving and rotating the launch slide, the mounting element (E) is brought into the definitive position (drawing number 2a and 2b). It is approached to ensure the vertical position with adjustable screw supports (3), to install the concrete support of the lining. At the same time, the mounting element of the covering (D) is brought with the slider (2.2) to the axis of the circular mounting grid, and by turning the receiving arm of the slider (2.1) and the horizontal movement of the leg of the slider (2.2), the element (D) is brought into the launch position, it is fastened with a steel rope on the winches driven by hydraulic motors (18) and over the rollers (1.2 and 1.3) is pulled by a steel rope (16) into position on the already assembled element (E). Moving the element in the direction of the tunnel axis is done by rollers (1.3).

At the same time, the element (C) is mounted on the launch slide, by moving the slide horizontally (2.2) and turning the arm (2.1) it is brought to the launch position, it is fastened with a steel rope (16) to the winches (18) driven by hydraulic motors and via rollers (1.2 and 1.3) drags it into position to the already mounted element (D) (drawing number 3a and 3b). It is temporarily clipped to the element (D), and only when mounting the first arc, the receiving element (9) is released, and it is lowered onto the launch ramp (2.1) to accept the element (B).

The same procedure is repeated for the mounting element (B).

At the same time, the element (A) is mounted on the launch slide (drawing no. 4a and 4b), by moving the slide horizontally (2.2) and turning the arm (2.1) it is brought to the definitive position (drawing no. 5a and 5b). The approach is to ensure the vertical position with adjustable screw supports (3), applying a compressive force of approx. 120 to 150 kN, with the obligatory provision of radial displacements of the joining points of the mounting elements with screw spacers (4) and only for the first arch, the following arches are held by lateral clamping in the already assembled arch, and install the concrete lining support. After that, the scaffolding serves as a support for the outer formwork (only for the first arch) for the installation of concrete in the space between the assembly lining and the tunnel cap (drawing no. 6a and 6b).

When performing the first arch, the scaffolding remains in that position until the outer concrete formwork is removed, for about twenty hours.

After removing the outer concrete formwork and loosening all supports, the scaffolding is lowered 90 mm and rests on four wheels (1.5 and 1.6), two of which are driving (1.5), on a longitudinal beam (5), which is supported on bearings adjustable in height and layout (6). By moving the drive wheels, the scaffold moves to a new position for mounting the new arch, which is mounted in the same way as described for the first arch, with the fact that the new arch is fixed with mounting and demountable clamps (10) for the already finished arch, and over the groove (7) and protrusion (8) (drawing number 7a and 7b and 8a and 8b).

The cross-section (drawing number 9a, 9b, 9c and 9d) shows the system of connecting the prefab elements in the direction of the tunnel axis via a conical groove (7) and a conical protrusion (8), and by assembly and disassembly connecting battens (10), which ensure the tightness of the arches during concreting of the intermediate space between the assembly elements and the tunnel cap. The same cross-section shows the method of supporting and moving the scaffolding from one working position to another.

The drawing number 10a and 10b and 10c shows the receiving element (9) with the element (11) for receiving the steel rope and the system (12) of holding the receiving element to the launch slide (2.1).

Drawing number 11a and 11b shows a three-dimensional mounting element "A", which is characterized by the fact that the lower part is designed to accept hydraulic jacks and adjustable screw supports (3 and 4) to ensure against vertical and horizontal displacement, the upper part is designed with a characteristic roller rib for clamping the mounting element "B". The sides are provided with five conical grooves (7) on one side and five conical protrusions (8) on the other side. On the inside, there are two plastic inserts with an internal thread for fixing the receiving element (9) for manipulation and assembly, and two plastic inserts with an internal thread on each side reinforcement of the assembly element, for attaching assembly and disassembly clamps (10) to ensure mutual adhesion of the old and the new arch during concreting of the space between the arch and the tunnel cap. After the assembly is completed, the plastic inserts are used for suspension of lighting, signaling, ventilation and the like, on the lining of the tunnel.

Drawings number 12a and 12b show the three-dimensional mounting element "B", "C" and "D", which are equal to each other, and which are characterized by the fact that the lower part is shaped with a cylindrical groove for connecting with the mounting element "A". , and the upper part is provided with a characteristic roller rib for clamping the mounting element "C". The sides are provided with five conical grooves (7) on one side and five conical protrusions (8) on the other side. On the inside, there are two plastic inserts with an internal thread for fixing the receiving element (9) for manipulation and assembly, and two plastic inserts with an internal thread on each side reinforcement of the assembly element, for attaching assembly and disassembly clamps (10) to ensure mutual adhesion of the old and the new arch during concreting of the space between the arch and the tunnel cap. After the assembly is completed, the plastic inserts are used for suspension of lighting, signaling, ventilation and the like, on the lining of the tunnel.

Drawing number 13a and 13b shows a three-dimensional mounting element "E", which is characterized by the fact that the lower part is designed to accept hydraulic jacks and adjustable screw supports (3 and 4) to ensure against vertical and horizontal movement, the upper part is designed with a characteristic roller groove for clamping the mounting element "D". The sides are provided with five conical grooves (7) on one side and five conical protrusions (8) on the other side. On the inside, there are two plastic inserts with an internal thread for securing the receiving element (9) and two plastic inserts with an internal thread on each side reinforcement of the mounting element, for attaching the mounting and dismounting clamps (10) to ensure the mutual adhesion of the old and new arch for time of concreting the space between the arch and the tunnel cap. After the assembly is completed, the plastic inserts are used for suspension of lighting, signaling, ventilation and the like, on the lining of the tunnel.

Drawing number 14 shows the mounting element "C" mounting system, the steel rope guiding system (16), which is manually placed on the mounting element (11), and the entire assembly (9, 11, "C") is pulled by means of a hydraulic motor ( 18) over the rollers 1.2 and 1.3 towards the definitive position, and on the passage of the lower receiving element (11) above the steel rope (17), it is automatically hooked by a special hook for the receiving element (11), and in this way we have the possibility of moving the mounting element in both directions, and what is important when moving the assembly element in the direction of the tunnel in order to engage the protrusions (8) in the grooves (7).

Drawing number 15a shows the side view of the formwork of the assembly element, drawing 15b the drawing of the formwork, drawing 15c the floor plan of the formwork, and drawing 15d the detail of the floor, all for the reason that the system of the lower floor (13) with a rigid steel part ( 13.1), rubber joints (13.2) and adjustable supports (13.3). With the adjustable supports of the lower floor (13.3), we bring the lower floor between the outer (13.4) and the inner formwork (13.5) into an inclined position according to the details of the project, so that the concreted assembly element, for the part of the lining of the tunnel in the curve, has the required trapezoidal shape.

Drawing number 16 shows the tunnel lining system with three prefabricated reinforced concrete elements in cross-section.

A detailed description of at least one way of realizing the invention

Production of prefabricated elements

The production of prefabricated elements is recommended in a closed area equipped with a crane with a load capacity of min. 50 kN, and sufficient space under the crane to house 50 molds for the production of prefabricated prefabricated elements, and space, also under the crane, to house a three-day production. There, the elements are placed in a way, depending on the available space, which enables the processing of the side sides for later gluing of the rubber tape, and the processing of the upper surface with a waterproofing coating, in the intermediate phase of shipping to the warehouse within the factory, or to the plateau in front of the tunnel. The plan trapezoidal elements required for the construction of the tunnel lining in the bend are performed using an adjustable floor (13) with rubber joints.

Assembly of elements in the road tunnel

The finished assembly elements are brought and deposited along the edge of the tunnel next to the scaffolding. There, the crane lifts them up and brings them above the launch ramp (2.1), to which they are attached to the launch ramp via the receiving element (9) using two screws. An endless conveyor chain pulls the launch ramp into the axis of the circular assembly scaffold. The assembly element "E" is mounted with the launch ramp in the definitive position, there it is fixed with adjustable screw supports (3 and 4), tightened with assembly-demountable clamps to the already installed element, and the concrete installation of the support of the assembly element is carried out. At the same time, the assembly element "D" is pulled into the axis of the circular assembly scaffold, by the launch ramp, and by means of the built-in hydraulic cylinders, element "D" is brought into the path for dragging to the installation site. In this position, the upper cable (16) is clipped to the receiving element (9) and the pulling of the element begins. When the element passes a path of approx. 4 m, the lower cable (17) is automatically clipped to the receiving element and the prefabricated concrete element "D" is dragged to its definitive position. There, with the help of cables and rollers (1.3), it is brought into a definitive position in the transverse and longitudinal sense. There, it is now tightened to the already mounted arch using the mounting and dismounting clamps (10), which are attached by means of screws in plastic dowels. After securing the element to the already mounted bow, the receiving element (9) is separated from the mounting element "D" and returned to the launch ramp (2.1) with cables, and the lower cable is separated from the receiving element automatically when element "D" passes the position of element "B" ". Now the upper cable is manually separated from the receiving element, which at that moment is automatically accepted on the launch pad, which now goes out with the receiving element by means of an endless chain to the place outside the circular scaffold for element "C". Element "C" is brought to the installation site in the same way as element "D", it is tightened to the already existing arch using assembly-dismantling clamps, after which the receiving element is released and returned to the launch pad. He goes to get element "B" and in the same way mounts it next to element "C" and the existing arch, tightens but not with full force to the existing arch, remains attached to the upper cable (16) until the launch ramp reaches element "A", attracts it is tightened with element "B" and assembly and disassembly ties, but not with full force against the existing arch. With hydraulic cranes supported on the heel of the arch and fixed to element "A", we introduce a longitudinal force of approx. 120 kN into the arch, and in this way the mounted arch takes over the load. We secure the heel of the arch in the vertical and horizontal direction with adjustable screw supports (3, 4), remove the hydraulic cranes and concrete the heel of the arch. Now the receiving element is released from the element "A" and "B", the circular self-propelled scaffolding is lowered onto the wheels and goes out of the assembled arch under its own power, it is fixed in the new working position and now serves as a pipe support for transporting concrete into the cavity between the tunnel shell and assembled arch made of prefabricated elements. In this way, the manipulation of the otherwise difficult concrete transport pipe is facilitated and accelerated, the ideal concreting of the arch is achieved gradually on one and the other side from the heel of the arch towards the crown in a width of approx. two-thirds of the prefabricated element, with a simple vibration of the concrete on one side while concreting on the other side of the arch. Immediately after concreting, the pipe support for concrete transport is removed and the installation of the new arch begins.

Method of application of the invention

By solving these technical problems, the following technical-technological characteristics are unified when applied in tunnel construction:

- the mounted parts in the arch unit make up the final treatment of the tunnel surface,

- a waterproofing layer on the outer surface and rubber seals on the sides form a waterproof layer,

- waterproofing is performed on a layer of shotcrete,

- the thickness of the shotcrete is reduced from approx. 25 cm to approx. 5 cm

- replaces the formwork for the construction of the monolithic lining of the tunnel,

- serves as formwork for the concrete filling, a

- fastening points for manipulation and assembly of panels are used to attach ventilation, tunnel lighting and other signaling equipment of the tunnel.

It is important to note that the self-propelled scaffolding for the circular assembly of prefabricated elements of the tunnel lining is also used for concreting the cavity between the arch and the tunnel cap, as it enables the guiding of the concrete transport pipe exactly along the circular arch with the same accessories as for the assembly of reinforced concrete elements, i.e. on the sliding the circular element "carriage" is attached to a pipe for transporting concrete with the possibility of moving the pipe in the direction of the tunnel.

In addition to tunnel linings with precast reinforced concrete elements, the scaffolding can be used with minor adaptations for the assembly of arched structures of halls, bridges and the construction of internal linings for installations, and similarly for the construction of ships, airplanes and other spaces with a rounded inner surface.

With minor structural changes, it can serve as a scaffolding for road tunnel maintenance and rehabilitation works with constant traffic, which is of inestimable importance for the use of tunnels during regular maintenance and rehabilitation works.

Claims (10)

1. Precast prefabricated reinforced concrete element "A" and "E" is characterized by the fact that its surfaces parallel to the longitudinal axis are curved in the radius of the designed tunnel lining, which is the upper surface provided with an economy that significantly reduces the weight of the element and the possibility of installation anchors for the attachment of the reinforcement for the connection of elements "A" and "E" with the concrete filling between the tunnel cap and the arch of prefabricated elements, which on the lower side is made in such a way as to enable easy attachment of hydraulic cranes and adjustable screw supports (3 and 4) to ensure against vertical and horizontal movement, the upper part is provided with a characteristic roller rib or groove for clamping the pre-assembled crown element "B" or the crown element "D", which is possible by using the adjustable floor (13) to make the pre-assembled element trapezoidal in plan view , which is waterproofed on its upper surface and part of the side surfaces, so that it is also a waterproofing element of the tunnel lining, which are its sides are covered with rubber cloth, so that the penetration of water through the slits between the mounting elements is prevented, and the rubber cloth also serves as a compensation for minor inaccuracies in the performance of the elements in the factory, which is provided on its sides with five conical grooves (7) on one side and five conical protrusions (8) on the other side, which are used to clamp together the elements of adjacent arches, which are fitted on the lower side with two plastic inserts with an internal thread for fixing the element (9) for manipulation and assembly, which consists of elements 9, 11 and 12, and two plastic inserts each with an internal thread on the left and right circular reinforcement for receiving element (10) for mutual tightening of prefabricated reinforced concrete elements of adjacent arches during concreting of the space between the tunnel cap and the arch. 2. Prefabricated side and crown prefabricated reinforced concrete element "B", "C" and "D", according to claim 1, is indicated by the fact that its surfaces parallel to the longitudinal axis are curved in the radius of the designed tunnel lining, which is its upper surface with savings that significantly reduce the weight of the element and the possibility of installing anchors for the connection of elements "B", "C" and "D" with the concrete infill between the tunnel cap and the arch of prefabricated elements, which is the upper and lower part provided with characteristic roller with a rib or a cylindrical groove for mutual clamping of the mounting elements in a line parallel to the axis of the tunnel, which is possible by using the adjustable floor (13) to make the mounting element trapezoidal in plan view, which is waterproofed on the upper surface and part of the side surfaces, so that it is at the same time and the waterproofing element of the lining of the tunnel, whose sides are covered with rubber cloth, so that the penetration of water through the gaps between the mounting elements is prevented, and the rubber cloth o it also serves as a compensation for minor inaccuracies in the performance of the elements in the factory, which is provided on its sides with five conical grooves (7) on one side and five conical protrusions (8) on the other side, which are used for mutual clamping of the elements of adjacent arches , which is equipped with two plastic inserts with an internal thread on the lower side for fixing the receiving element (9) for manipulation and assembly, which consists of elements 9, 11 and 12, and two plastic inserts with an internal thread on the left and right to the circular reinforcement for receiving the element (10) for mutual tightening of the elements of the adjacent arches during the concreting of the space between the tunnel cap and the arch. 3. Acceptance element composed of positions 9, 11, and 12, for acceptance of mounting elements of the tunnel lining "A", "B", "C", "D" and "E" to the launch slide (2.1, 2.2), according to patent requirements 1 to 2, it is characterized by the fact that, with its geometrical cross-section shape, rubber supports enable the mounting element of the lining to be easily pulled along the slide (2.1), and prevent movement downwards and out of the given path, which has special fasteners (11 and 12) for traction and braking steel rope with the possibility of turning the steel rope around the fastening element, and automatic coupling and uncoupling of the lower steel rope. 4. The adjustable screw support (3) and spacer (4) for securing against vertical and horizontal movement, according to patent claims 1 to 3, is indicated by the fact that it has a sliding rubber-steel protection on three sides that serves as a formwork for the monolithic concrete bearing of the prefabricated linings of the tunnel, so that after hardening and achieving sufficient strength of the concrete, the adjustable screw support can be loosened and removed and used again during the next shoring or breaking. 5. The adjustable floor of the circular formwork (13) for the production of prefabricated prefabricated elements of the tunnel lining, trapezoidal in plan view, according to patent claims 1 to 4, is characterized by the fact that the steel parts of the circular floor (13.1) are connected to each other by a rubber element (13.2) that enables minimum deformation, so that the circular segment turns into an ellipsoidal element, and at each rubber joint the floor is supported by an adjustable support (13.3). 6. The procedure for installing prefabricated elements using a self-propelled scaffold for the circular installation of prefabricated elements using elements according to patent claims 1 to 5 is indicated by the fact that it accepts the prefabricated concrete elements in the free tunnel space immediately in front of it with elements "2.1" and "2.2", and by rotating and by longitudinal dragging, it brings it to the axis of the circular support "1.1" and brings it there to the definitive position, if it is about elements "A" or "E", and to the position for launching into circular assembly, if it is about elements "B", C" and "D", and the elements from the launch part (2.1 and 2.2) along a circular path determined by the position of the rollers "1.2" and "1.3", and by means of a winch with a hydraulic motor (18), are brought to the position from which, by moving in the longitudinal direction of the tunnel with the help of rollers "1.3" they are brought to the designed definitive position, and the release and movement from the finished part to the new working position is carried out automatically along the metal track (5), which is supported on self-adjusting bearings (6) in height and layout, and after bringing the scaffolding to the new and working position, lifts and moves the steel track to a new position for repeated movement with the possibility of simultaneous operations on the concreting of the space between the tunnel cap and the arch. 7. The procedure for controlling interdependent work processes for the circular installation of prefab elements with self-propelled scaffolding, according to patent claims 1 to 6, is indicated by the fact that all work processes are remotely controlled, which are automated so that the start of a single action is impossible, if all are not fulfilled conditions for the safety of people and actions that are already in progress, which safely and without dynamic shocks start and stop the scaffolding, which makes it possible to start driving and stop the launch slide without dynamic shocks, regardless of whether it is loaded or empty, which enables the precise placement of elements in place installation. 8. The lining of the tunnel from prefabricated reinforced concrete elements and the manufacturing and installation process, according to patent claims 1 to 7, is indicated by the fact that it also serves for concreting the cavity between the arch and the tunnel cap, because it enables the routing of the concrete transport pipe exactly along the circular arc with with the same accessory as for the assembly of reinforced concrete elements, that is, a pipe for transporting concrete with the possibility of moving the pipe in the direction of the tunnel is attached to the sliding circular element ("carriage"). 9. The lining of the tunnel from prefabricated reinforced concrete elements and the manufacturing and installation process, according to patent claims 1 to 8, is indicated by the fact that, with minor adaptations, it is also used for the assembly of arched structures of halls, bridges and the execution of internal linings of installations and the like, during construction ships, planes and other spaces with a rounded inner surface. 10. The lining of the tunnel made of prefabricated reinforced concrete elements and the manufacturing and installation process, according to patent claims 1 to 9, is indicated by the fact that, with minor adaptations, it also serves as a working scaffold for the maintenance of road tunnels and for rehabilitation works with constant traffic, and which is of inestimable importance for the use of the tunnel and during regular maintenance and rehabilitation works.