WO2019149945A2

WO2019149945A2 - A method for submerging a modular tunnel

Info

Publication number: WO2019149945A2
Application number: PCT/EP2019/052676
Authority: WO
Inventors: Tõnu ADER
Original assignee: Ader Tonu
Priority date: 2018-02-02
Filing date: 2019-02-04
Publication date: 2019-08-08
Also published as: WO2019149945A3; EE201800003A; EE05838B1

Abstract

The specificity of a method for submerging a modular floating tunnel with flexible seals pressurized from inside and threaded pullers is that the cylindrical modules from reinforced concrete, necessary for the construction of the tunnel, are assambled from prefabricated sections directly on the mobile submerging platform, where the modules are one by one attached to the end of the already mounted tunnel that reaches to the water surface and continuously submerged into the water so that the tunnel remains entirely dry inside. This is possible because the modules are joined together with threaded pullers and sealed with flexible seals, pressurized from inside, what makes possible to turn the tunnel end uppward. Compared to the known solutions, it will significantly accelerate the mounting and reduce the cost of building underwater tunnels.

Description

A method for submerging a modular tunnel

with pullers and pressurable seals

Technical field

The invention relates to the field of underwater tunnels (E02D 29/073).

The invention is applicable forthe same purposes as conventional tunnels, i.e. for crossing waterbodies, but this method for submerging a modular tunnel with pullers and pressurable seals allows tunnels to be built more quickly and also at a lower cost, compared to methods known in the past.

The technical level

The object of the present invention is to simplify and speed up the construction of underwater tunnels, making it possible to interconnect industrially manufactured and easily assembled tunnel modules and launch the tunnel from a mobile submerging platform, using a method similartothe construction of underwater gas pipelines.

Since the tunnel below the water surface has several advantages over bridges and bored into the seabed tunnels, experiments have been carried out to build underwater concrete tunnels already in the 19th century and a wide range of technical solutions has been proposed. To date, a wide range of technical solutions and methods forthe construction of concrete submersible tunnels have been patented, for example:

US 3478521 A underwater floating and to required level submerged tunnel composed from prefabricated tunnel units;

EP 0034907 B1 A submerged tunnel and a method of, and means for, constructing a submerged tunnel.

However, the practical construction of underwater tunnels has proved technically too complex and the construction of longer tunnels is too costly. Since the construction of a large monolithic tunnel in the water is technically too complicated, the tunnel must be constructed from modules to be connected one by one to the tunnel under construction in the required location. The concrete tunnel tube made from modules is technically not easy to submerge as it does not bend. Without the bending of the tunnel pipe, the tunnel underwater must be fully submerged all at once; or every module to be added needs to be fully submerged and added to the tunnel underwater. Both methods create a series of technical problems. Therefore, only shorter tunnels have proved possible and their cost has proved to be economically resonable only in special cases. This particular modular tunnel with pullers and pressurable seals allows automation of the construction of an underwater tunnel and reduction of the amount of diver manhours needed. Comparing to the solutions used so far, this method makes construction of an underwater tunnels economically feasible and allows to build various types of longer and shorter tunnels.

The method of connecting tunnel parts with pullers and pressurable sealings can also be applied to connecting larger modules of immersed tunnels.

The nature of the invention

The nature of the present invention is a method for connecting large diameter reinforced concrete modules 1 of a underwater tunnel that makes it possible to add modules 1 to the tunnel on the surface of the water, directly on a moving submerging platform, via setting the required angle between the modules 1, which prevents water from entering the tunnel at the assembling stage.

Modules 1 can be assembled both in the manufacturing plant or on the site where it is launched from a special mounting vessel or a mobile submerging platform standing on the bottom of the water body.

To ensure the safety of the underwater tunnel, rescue capsules 7 are attached to the tunnel modules ata certain distance, which allow the evacuation of people from the tunnel in the event of an emergency.

List of drawings

The technical nature of the invention is explained by the following images:

Fig.1 Location of the tunnel in the body of water (sheet 1/8);

Fig.2 Metal parts of sector element 11 of the module 1 of tunnel (sheet 2/8);

Fig.3 One of ten sector elements 11 of the tunnel module 1 (sheet 3/8);

Fig.4 T unnel module 1 assembled (sheet 4/8);

Fig.5 T unnel modules 1, seal 2 and escape capsule 7 (sheet 5/8);

Fig.6 The image of the connection between the modules 1 (sheet 6/8);

Fig.7 The image of setting modules 1 at an angle (sheet 7/8);

Fig.8 The image of the anchoring of the module 1 (sheet 8/8);

An example of building of a modular sumerged tunnel with pullers and pressurable seals

A modular tunnel with pullers and pressurable seals can be submerged and anchored to the bottom directly from a special mobile submerging platform. The main parts of the modular tunnel submerged into water from the platform are 20 m long and 8-14 m in diameter cylinder-shaped modules 1 , which are assambled from about 10 sector elements 1 1 directly on the assembly platform at the tunnel submerging site. The pre stressed concrete sector elements 1 1 are produced in a factory and transported to the submerging platform.

The profiled metal ends 1 12 of each of the sector element 1 1 have been welded to the ends of the reinforcement of the sector element 1 1 before the concrete casting and to some ends of the longitudinal reinforcement rods are welded threaded rods 1 1 1. One end of the sector element 1 1 have a right hand threaded rods 11 1 and the other end of the sector element 1 1 has left hand threaded rods 1 11. It makes possible to connect one module 1 with another module 1 with pullers (connecting joints) 1 13, which have internal threads, in one end right hand and in oppsite end left hand thread. The end faces 1 12 of the sector elements 1 1 are made of a necessary thickness of rolled steel, which is rolled into a groove for fixing the seals 2. The side faces 1 14 of the sector elements 1 1 are made from rolled steal and intended to match to each other by a weld and an adhesive joint. Before the assembly of the modules 1 and interconnecting with joints from pullers 113, between the ends of the modules 1 are placed the pressurable from inside seal 2 of elastic material with a profile with corresponding to the modules 1 ends 1 12 shape and fastened with adhesive. Thereafter threaded rod 1 11 of the one module 1 are matched with threaded rod 1 1 1 of the next module 1 and connected to each other with pullers 1 13. After which the sea l 2 internal compa rtment is pressurized to the required extent, modules connection and all exterior surface of the module is covered with a special waterproof elastic coating 3 of a few millimeters thickness.

Additiona lly can be installed necessary internal fittings for module 1 , for example walls and railways. Then, adjusting the pullers 113, the last attached module 1 is set to a light upward angle in relation to the preceding module 1. C reating this angle is necessary for bending the end part of the tunnel (of about last ten attached tunnel modules, currently involved to the submerging process), so that the last module extending to the

submerging platform will have approximately 10 degrees (10e) angle to the water surface. This allows the modules to be added to the tunnel directly above the surface of the water and to keep tunnel completely dry inside. T o create such an a ngle (about one degree from the longitudinal axis of the tunnel modules 1 ), the pullers 1 13 on the upper parts of the tunnel modules 1 are turned to pull the threaded rods 11 1 to the required extent and thus making the distance between the upper parts of the two modules 1 to reduce. Reducing the distance between end surfaces 1 12 of the module 1 is possible due to squeezing of the elastic and pressurabre from inside sealing 2. S ealing 2 elastic squeezing with deformation of filled with pressured gas inner chambers), presses the outer surface of the seal 2 to a somewhat protruded position in a location of the most retracting parts of modules end, but does not break the tightness of the connection.

On either side of the tunnel, one continuous anchor rope 6 is placed, which, upon submerging process, functions as the submerging rope and binds the submerged tunnel to the submerging platform, passing in zigzag way via the rope blocks 51 of the anchors 5 and of the rope blocks 41 of the saddle-assembly 4, mounted on each of the modules 1. By means of tighting of two anchor ropes 6 and mowing forward the submerging platform, the module 1 is slowly submerged to the underwater position and prepared for connecting with new module 1. For lowering the boyancy forces of the submerging modules 1 and for decreasing necessary for submerging pulling forces to ropes 6, additional load, movable inside of the tunnel, can be used. When the module 1 is submerged to the required depth, the desired direction of the tunnel is adjusted with pullers 113, and then the required pressure of the gas (or fluid) of the interior of the sealing 2 will be adjusted. Finally, the submerging ropes 6 are fixed to the rope blocks 41 and 51 so that the continuous sections of the submerging ropes 6 mounted between the rope blocks 41 and 51 will remain as the fixed length anchor ropes 6 for particular module 1.

To build a modular tunnel with pullers and pressurable seals submerged from platform, the track with a suitable bottom conditions and the junction of the tunnel to the shore will be selected, the necessary research and design work will be done, and then a bottom of the water body will be prepared to install anchors 5. The optimal amount of the anchors 5 is two anchors 5 for the connection of each modules 1. The anchors 5 are arranged in pairs near by the connection of modules 1, one on eache side of the tunnel module 1. The anchors 5 are not being positioned directly below the tunnel but on the right distance to form an acute angle, to prevent the horisontal drift of the tunnel due to the water currents. So each anchor 5 has two anchor ropes 6 from which one is attached to the one of the nearest module 1 saddle assembly 4 and the other one to the another nearest module 1 saddle assembly 4. Thus, each module 1 of the fully submerged tunnel is anchored to the bottom with four adjacent to the module 1 anchors 5, by means of four anchor ropes 6, which connect anchor 5 rope blocks 51 with rope blocks 41 of the saddle-assembly 4. The use of the saddle-assembly 4 is desirable for dispersing loads generated by anchoring tunnel modules 1 over the upper sector elements 11 of the module 1. Forthe construction of anchor units there is a special anchoring device on the ship or platform that drills the required depth and shape bore into the soil, and then the anchoni 5 threaded stake will be screwed there. The calculated payload for anchor 5 is 100-300 tons.

In case, if the tunnel construction works must be temporarily suspended due to deteriorating weather conditions, the open end of the last connected to the tunnel module 1 will be closed with a special watertight end wall (or hinged shutter) and the tunnel end is submerged to a reasonable depth to reduce the wave loads. To continue the construction works the tunnel modules can be raised to the water surface and the end wall will be opened.

T o increase the overall safety level of the tunnel a certain quantity of the hinged tunnel shutters, thatcoverthe entire cross-section of the tunnel, can be installed forthe event of emergency.

The field of use of the submerged from mobile platform modular tunnel with pullers and pressurable seals is wide and such tunnels can be used for crossing straits, seawater, lakes and rivers.

The submereged into water from the mobile platform modular tunnel with pullers and pressurable seals can be built for both rail and road transport, with both unidirectional and two-way transport. If the process of the compilation and submerging of a module will be sufficiently automated, significant construction costs will be reduced by a significant decrease in underwater labor.

Due to high level of withstanding to seismic impacts and low sensitivity to environmental impacts (changes in ambient air temperature, winds, snow cover and icing), submerged from the mobile platform modular tunnel with pullers and pressurable seals can also be built in places with difficult weather conditions.

Compilation of the modules 1 from several smaller longitudinal sections (sector elements 11) is necessary in order to simplify and automate the production and storage process by reducing the size and weight of the required concrete elements. It is also important to reduce the weight and gauge of the tunnel parts in order to reduce their transport costs from the production site of the tunnel elements to the tunnel construction site.

The environmental impacts, of the construction and use of submerged modular tunnel with pullers and pressurable seals, are not large.

Claims

PATENT CLAIMS

1. Method for submerging of a modulartunnel, where pullers and pressurized seals are used to connect tunnel modules differs in thatthe modules are connected to each other with adjustable pullers and the ends of modules are sealed with a flexible and pressurized from inside seal of special profile, which makes possible the watertight connection of the modules to each other and the necessary correction of the direction of the tunnel during submerging and in water.

2. The modular submerged tunnel with pullers and pressurized seals differs in that, in orderto achieve additional waterproofness, the connections between modules (1) and also the modules (1) themselves are covered with a layer of a few millimeters thick elastic plastic (3).

3. The modular submerged tunnel with pullers and pressurized seals differs in that, if the assembly of the tunnel from modules (1) is temporarily interrupted (for example in case of adverse weather conditions), the end of the last connected to the tunnel module 1 is closed watertightly with a special watertight end wall (or articulated hutch) and the end part of the tunnel is temporarily deepened to a suitable depth to reduce wave loads.

4. The modular submerged tunnel with pullers and pressurized seals differs in that, the required anchors (5) are fixed in bottom soil with special threaded stakes screwed into the drilled pits of required shape and depth, depending on the type of soil on the bottom of waterbody, forwhatthe mobile platform orvessel is equiped with a special drilling tower located on special movable console.

5. The modular submerged tunnel with pullers and pressurized seals differs in that, the tunnel anchors (5) are provided with rope blocks (51) and the saddle-assembly (4) of the modules (1) are provided with rope blocks (41) for tunnel submerging with the continuous rope.

6. The modular submerged tunnel with pullers and pressurized seals differs in that, in orderto ensure the safety of people using the tunnel, escape modules (7) are placed at a certain distance along the tunnel and such escape modules (7), which have two watertight hatches, to ensure the waterproofness of both the tunnel and the escape module (7) after the opening of the locking device between them, allow the escape module (7) to be fully separated from the tunnel, if a need to rise to the water surface in an emergency arises.